# CalculatePilot: full index

> Complete list of CalculatePilot's free online calculators and guides, one line each. Every calculator page shows its formula, a worked example and sources, runs in the browser and needs no account. Results are estimates, not professional financial, medical or legal advice.

Short version: https://www.calculatepilot.com/llms.txt
Sitemap index: https://www.calculatepilot.com/sitemap.xml

## Financial calculators (55)

- [1031 Exchange Calculator — Deferred Gains & Boot](https://www.calculatepilot.com/financial/1031-exchange-calculator.html): Free 1031 exchange calculator: estimate deferred capital gains and recapture tax, check for cash or mortgage boot, and get your 45- and 180-day deadlines.
- [401(k) Calculator 2026 — Employer Match & Growth](https://www.calculatepilot.com/financial/401k-calculator.html): Free 2026 401(k) calculator: project your balance with employer match, raises and the $24,500 limit plus catch-up, with a year-by-year schedule.
- [Amortization Calculator — Schedule & Extra Payments](https://www.calculatepilot.com/financial/amortization-calculator.html): Free amortization calculator: full monthly or annual schedule of principal and interest, the crossover month, payoff date and savings from extra payments.
- [Annuity Calculator — Lifetime Income & Value](https://www.calculatepilot.com/financial/annuity-calculator.html): Free annuity calculator: estimate lifetime income from an immediate or deferred annuity, compare payout options, and find future and present value.
- [Auto Loan Calculator — Monthly Car Payment](https://www.calculatepilot.com/financial/auto-loan-calculator.html): Calculate your monthly car payment including trade-in value and sales tax. Free and instant. Free, instant, formula shown. No signup.
- [Bond Calculator — Price, Yield & Duration](https://www.calculatepilot.com/financial/bond-calculator.html): Free bond calculator: find a bond's fair price from face value, coupon rate, maturity and market rate, plus yield to maturity and duration.
- [Budget Calculator — 50/30/20 Rule](https://www.calculatepilot.com/financial/budget-calculator.html): Calculate a suggested monthly budget split between needs, wants, and savings using the popular 50/30/20 rule. Free, instant, formula shown. No signup.
- [Car Affordability Calculator](https://www.calculatepilot.com/financial/car-affordability-calculator.html): Calculate the maximum car price you can afford based on your monthly budget, interest rate, and down payment. Free, instant, formula shown. No signup.
- [CD Calculator](https://www.calculatepilot.com/financial/cd-calculator.html): Calculate the maturity value and interest earned on a certificate of deposit (CD) based on your deposit, rate, and term.
- [CD vs High-Yield Savings Calculator](https://www.calculatepilot.com/financial/cd-vs-hysa-calculator.html): Free CD vs HYSA calculator: compare a fixed-rate CD with a high-yield savings account under rate-cut scenarios, with deposits and penalty break-even.
- [529 College Savings Calculator — Project Growth](https://www.calculatepilot.com/financial/college-savings-calculator.html): Calculate how much your 529 college savings plan will grow. Enter starting balance, monthly contributions, return rate, and years to see projected college.
- [Commission Calculator — Flat, Tiered & Split](https://www.calculatepilot.com/financial/commission-calculator.html): Free commission calculator: sales or real estate commission at a flat or tiered rate, your take-home after a split and fees, and sales needed for a goal.
- [Compound Interest Calculator with Contributions](https://www.calculatepilot.com/financial/compound-interest-calculator.html): Free compound interest calculator: project growth with regular deposits, any compounding frequency, inflation-adjusted value and a yearly schedule.
- [Credit Card Payoff Calculator](https://www.calculatepilot.com/financial/credit-card-calculator.html): Calculate how long it will take to pay off a credit card balance and how much interest you'll pay. Free, instant, formula shown. No signup.
- [Credit Utilization Calculator](https://www.calculatepilot.com/financial/credit-utilization-calculator.html): Calculate your credit utilization ratio, a major factor in your credit score, based on your balances and credit limits. No signup needed. CalculatePilot.
- [Currency Converter — Exchange Rate & Fees](https://www.calculatepilot.com/financial/currency-converter.html): Free currency converter: convert any amount at the exchange rate you enter, see what bank and card fees really cost, and compare transfer providers.
- [Debt Payoff Calculator — Snowball vs Avalanche](https://www.calculatepilot.com/financial/debt-payoff-calculator.html): Free debt payoff calculator: compare avalanche, snowball and minimum payments to see your debt-free date, total interest and a monthly payoff plan.
- [Debt-to-Income Ratio Calculator — DTI Checker](https://www.calculatepilot.com/financial/debt-to-income-ratio-calculator.html): Calculate your debt-to-income ratio (DTI) instantly. See front-end vs. back-end DTI, what lenders actually consider a good ratio, and how to lower yours.
- [Discount Calculator — Sale Price & Amount Saved](https://www.calculatepilot.com/financial/discount-calculator.html): Free discount calculator: sale price and amount saved from original price and percent off. Includes stacked discounts. No signup.
- [Down Payment Calculator](https://www.calculatepilot.com/financial/down-payment-calculator.html): Calculate how much you need for a down payment and the resulting loan amount based on home price and down payment percentage.
- [Emergency Fund Calculator](https://www.calculatepilot.com/financial/emergency-fund-calculator.html): Calculate your target emergency fund size and how many months it will take to reach it based on your savings rate. Free, instant, formula shown. No signup.
- [Freelance Hourly Rate Calculator — Set Your Rate](https://www.calculatepilot.com/financial/freelance-rate-calculator.html): Calculate the hourly rate you need to charge as a freelancer to hit your income goal, accounting for expenses and taxes.
- [HELOC Calculator — Home Equity Line Payments](https://www.calculatepilot.com/financial/heloc-calculator.html): Free HELOC calculator: estimate interest-only and repayment-period payments on a home equity line of credit from your limit, rate and draw period.
- [House Affordability Calculator — Max Home Price](https://www.calculatepilot.com/financial/house-affordability-calculator.html): Estimate the maximum home price you can afford based on your income, debts, down payment, and interest rate. Free, instant, formula shown. No signup.
- [House Flip Calculator](https://www.calculatepilot.com/financial/house-flip-calculator.html): Estimate the profit and ROI on a house flip based on purchase price, rehab costs, and expected resale value. Free, instant, formula shown. No signup.
- [Inflation Calculator](https://www.calculatepilot.com/financial/inflation-calculator.html): Calculate how inflation affects the future cost of goods and the future purchasing power of your money. Free, instant, formula shown. No signup.
- [Investment Calculator — Project Portfolio Growth](https://www.calculatepilot.com/financial/investment-calculator.html): Calculate how an investment grows over time with compound returns and regular contributions. Free, instant, formula shown. No signup.
- [Car Lease Calculator](https://www.calculatepilot.com/financial/lease-calculator.html): Calculate your estimated monthly car lease payment based on vehicle price, residual value, term, and money factor. Free, instant, formula shown. No signup.
- [Loan Calculator — Monthly Payment & Total Cost](https://www.calculatepilot.com/financial/loan-calculator.html): Free loan calculator: monthly payment, total interest and the true cost including origination fees, with the formula explained. No signup needed.
- [Mortgage Calculator — Payment with Taxes & PMI](https://www.calculatepilot.com/financial/mortgage-calculator.html): Free mortgage calculator: monthly payment with property tax, insurance, HOA and PMI, 30- or 15-year and ARM options, extra payments and amortization.
- [Net Worth Calculator — Compare by Age](https://www.calculatepilot.com/financial/net-worth-calculator.html): Free net worth calculator: total your assets and debts, see your debt-to-asset ratio and liquid assets, and compare with Federal Reserve medians for your age.
- [Paycheck Calculator 2026 — Take-Home Pay](https://www.calculatepilot.com/financial/paycheck-calculator.html): Free 2026 paycheck calculator: take-home pay per paycheck after federal tax, Social Security, Medicare, state tax and pre-tax deductions like 401(k).
- [Refinance Calculator](https://www.calculatepilot.com/financial/refinance-calculator.html): Compare your current loan payment to a new refinanced rate and see your monthly savings and breakeven point. Free, instant, formula shown. No signup.
- [Rent Calculator — How Much Rent Can You Afford](https://www.calculatepilot.com/financial/rent-calculator.html): Calculate how much rent you can afford based on your income, using the common 30% guideline. Free, instant, formula shown. No signup.
- [Rental Yield Calculator — Gross & Net Rental ROI](https://www.calculatepilot.com/financial/rental-yield-calculator.html): Calculate the gross and net rental yield on an investment property based on price, rent, and expenses. Free, instant, formula shown. No signup.
- [Retirement Calculator — FIRE Number & Withdrawals](https://www.calculatepilot.com/financial/retirement-calculator.html): Free retirement and FIRE calculator: find your FIRE number with the 4% rule, when you reach it, Coast FIRE, and how long your money lasts.
- [Roth IRA Calculator 2026 — Growth vs Traditional](https://www.calculatepilot.com/financial/roth-ira-calculator.html): Free 2026 Roth IRA calculator: project tax-free growth with the $7,500 limit and phase-outs, a yearly ledger and a Roth vs Traditional comparison.
- [Salary Calculator — Hourly to Annual Pay](https://www.calculatepilot.com/financial/salary-calculator.html): Free salary calculator: convert between hourly, weekly, monthly and annual pay from your hours, and see total compensation with benefits.
- [Sales Tax Calculator — Tax Amount & Final Price](https://www.calculatepilot.com/financial/sales-tax-calculator.html): Free sales tax calculator: tax amount and final price from pre-tax price and rate. Also reverse the tax. No signup. Free, instant, formula shown. No signup.
- [Savings Calculator — Future Value of Deposits](https://www.calculatepilot.com/financial/savings-calculator.html): Free savings calculator: see how a starting balance and regular deposits grow with interest, with the future value and a year-by-year breakdown.
- [Savings Goal Calculator — Time to Reach a Target](https://www.calculatepilot.com/financial/savings-goal-calculator.html): Calculate how long it will take to reach a specific savings goal based on your monthly contribution and interest rate. Free, instant, formula shown. No signup.
- [Scotland Stamp Duty Calculator (LBTT) 2026](https://www.calculatepilot.com/financial/scotland-lbtt-calculator.html): Scotland stamp duty calculator (LBTT): first-time buyer relief, 8% ADS, and non-residential £465,000 = £11,750. Not English SDLT.
- [Scottish Income Tax Calculator 2026/27](https://www.calculatepilot.com/financial/scotland-take-home-pay-calculator.html): Scottish take-home pay for 2026/27: all six income tax bands, UK National Insurance, and how your pay compares with England, Wales and NI.
- [Seller Net Sheet Calculator — Home Sale Proceeds](https://www.calculatepilot.com/financial/seller-net-sheet-calculator.html): Free seller net sheet calculator: estimate net proceeds from a home sale after agent commission, mortgage payoff, transfer taxes, title fees and credits.
- [Simple Interest Calculator — I = P × r × t](https://www.calculatepilot.com/financial/simple-interest-calculator.html): Free simple interest calculator: interest and total amount from principal, rate and time, with a year-by-year schedule and the formula shown.
- [Student Loan Calculator — Monthly Payment & Payoff](https://www.calculatepilot.com/financial/student-loan-calculator.html): Free student loan calculator: monthly payment, total interest and payoff date for federal or private loans, with income-based repayment estimates.
- [Income Tax Calculator 2026 — Federal, State & FICA](https://www.calculatepilot.com/financial/tax-calculator.html): Free 2026 income tax calculator: federal tax with 2026 IRS brackets, standard or itemized deduction, 401(k) and HSA, FICA and an optional state estimate.
- [UK Mortgage Overpayment Calculator](https://www.calculatepilot.com/financial/uk-mortgage-overpayment-calculator.html): Free UK mortgage overpayment calculator: interest and years saved by regular or lump-sum overpayments, the 10% ERC allowance and a yearly balance.
- [UK Mortgage Repayment Calculator](https://www.calculatepilot.com/financial/uk-mortgage-repayment-calculator.html): UK mortgage repayment calculator: compare a repayment mortgage with interest-only on the same loan in pounds, with monthly cost and total interest.
- [UK Stamp Duty Calculator (SDLT) 2026](https://www.calculatepilot.com/financial/uk-stamp-duty-calculator.html): Free SDLT calculator for England and NI: stamp duty with first-time buyer relief, 5% second-home surcharge, non-UK resident and company rates.
- [Stamp Duty Comparison — England, Scotland & Wales](https://www.calculatepilot.com/financial/uk-stamp-duty-comparison.html): Compare SDLT, Scottish LBTT and Welsh LTT on one price: main home, first-time buyer, additional property and non-residential, side by side.
- [UK Student Loan Repayment Calculator 2026/27](https://www.calculatepilot.com/financial/uk-student-loan-repayment-calculator.html): Work out UK student loan deductions from your salary with GOV.UK 2026/27 Plan 1, 2, 4, 5 and postgraduate thresholds, per month and per year.
- [UK Take-Home Pay Calculator 2026/27](https://www.calculatepilot.com/financial/uk-take-home-pay-calculator.html): Free UK take-home pay calculator for 2026/27: income tax for England, Wales, NI or Scotland, National Insurance, pension, student loan and tax codes.
- [VAT Calculator — Add or Remove VAT](https://www.calculatepilot.com/financial/vat-calculator.html): Free VAT calculator: add or remove VAT from any price, see how much VAT is included, with UK, EU and international rates. Instant, no signup.
- [Wales Stamp Duty Calculator (LTT) 2026](https://www.calculatepilot.com/financial/wales-ltt-calculator.html): Wales stamp duty calculator (LTT): £225,000 nil band, higher rates, and non-residential £300,000 = £2,750. The old £150,000 nil band is not used.

## Health and fitness calculators (30)

- [Alcohol Calories Calculator — Beer, Wine & Spirits](https://www.calculatepilot.com/health/alcohol-calories-calculator.html): Free alcohol calories calculator: calories in any drink from size, ABV and sugar, plus US standard drinks, UK units and what weekly drinking adds up to in a year.
- [BAC Calculator — Blood Alcohol Estimate (Widmark)](https://www.calculatepilot.com/health/bac-calculator.html): Free BAC calculator: estimate blood alcohol from standard drinks or drink size and ABV, weight, sex and time, with an hour-by-hour decline. Educational estimate only.
- [Blood Pressure Calculator — AHA Categories](https://www.calculatepilot.com/health/blood-pressure-category-calculator.html): Free blood pressure calculator: check your AHA category from normal to severe, average up to three readings, and see pulse pressure and MAP.
- [BMI Calculator — Body Mass Index for Adults](https://www.calculatepilot.com/health/bmi-calculator.html): Free BMI calculator for adults: your BMI and WHO category from height and weight, healthy weight range, BMI Prime and New Oxford BMI, metric or imperial.
- [BMR Calculator — Basal Metabolic Rate](https://www.calculatepilot.com/health/bmr-calculator.html): Free BMR calculator: calories burned at rest from Mifflin-St Jeor, Harris-Benedict, Katch-McArdle and Cunningham, and how BMR changes with age.
- [Body Fat Calculator — Navy Tape & Skinfold](https://www.calculatepilot.com/health/body-fat-calculator.html): Free body fat calculator: body fat % by the U.S. Navy tape method or Jackson-Pollock skinfolds, with fat mass, lean mass and your ACE category.
- [Body Frame Size Calculator — Wrist & Height Method](https://www.calculatepilot.com/health/body-frame-size-calculator.html): Free body frame size calculator: find out if you have a small, medium or large frame from your wrist and height using the ratio method and the MedlinePlus chart.
- [Calorie Calculator — Lose, Maintain or Gain](https://www.calculatepilot.com/health/calorie-calculator.html): Free calorie calculator: maintenance calories and a daily target to lose or gain weight, with a week-by-week projection to your goal and macros.
- [Calories Burned Calculator — 28 Activities](https://www.calculatepilot.com/health/calories-burned-calculator.html): Free calories burned calculator using 2024 Compendium MET values for 28 activities: total and net calories, intensity level and guideline minutes.
- [Due Date Calculator — LMP, Conception or IVF](https://www.calculatepilot.com/health/due-date-calculator.html): Free due date calculator: estimate your due date from your last period, conception or IVF transfer, with weeks pregnant, trimester and milestones.
- [Fiber Intake Calculator — Daily Fiber Target](https://www.calculatepilot.com/health/fiber-intake-calculator.html): Free fiber calculator: your daily fiber target from calories (14 g per 1,000 kcal) and the IOM reference by age and sex, plus foods and a step-up plan.
- [Healthy Weight Range Calculator by Height](https://www.calculatepilot.com/health/healthy-weight-range-calculator.html): Free healthy weight range calculator: the weight range for a healthy BMI at your height, NICE lower thresholds for some ethnic groups, and time to reach it.
- [Ideal Weight Calculator — 4 Formulas Compared](https://www.calculatepilot.com/health/ideal-weight-calculator.html): Free ideal weight calculator: compare the Devine, Robinson, Miller and Hamwi formulas for your height, adjust for frame size, and see your healthy range.
- [Lean Body Mass Calculator — LBM & FFMI](https://www.calculatepilot.com/health/lean-body-mass-calculator.html): Free lean body mass calculator: compare the Boer, James and Hume formulas, calculate LBM from a known body fat %, and get your fat-free mass index (FFMI).
- [Macro Calculator — Protein, Fat & Carb Grams](https://www.calculatepilot.com/health/macro-calculator.html): Free macro calculator: turn daily calories into protein, fat and carb grams with goal presets, a check against the official AMDR ranges, and macros per meal.
- [One Rep Max Calculator — 1RM & Training Loads](https://www.calculatepilot.com/health/one-rep-max-calculator.html): Free one rep max calculator: estimate your 1RM with seven published formulas including Epley and Brzycki, plus NSCA training loads for your goal.
- [Ovulation Calculator — Fertile Window](https://www.calculatepilot.com/health/ovulation-calculator.html): Free ovulation calculator: estimate ovulation and your 6-day fertile window for the next six cycles, with a wider range for irregular cycles.
- [Running Pace Calculator — Pace, Time & Splits](https://www.calculatepilot.com/health/pace-calculator.html): Free running pace calculator: pace per mile and km from any race time, finish time from a target pace, even splits and Riegel race time predictions.
- [Period Calculator — Next Periods & Regularity](https://www.calculatepilot.com/health/period-calculator.html): Free period calculator: predict your next six periods from your last period, cycle and period length, and check cycle regularity against FIGO limits.
- [Pregnancy Calorie Calculator — By Trimester](https://www.calculatepilot.com/health/pregnancy-calorie-needs-calculator.html): Free pregnancy calorie calculator: daily calories for each trimester and while breastfeeding using IOM energy additions, with key nutrient targets.
- [Pregnancy Weight Gain Calculator — IOM Ranges](https://www.calculatepilot.com/health/pregnancy-weight-gain-calculator.html): Free pregnancy weight gain calculator: recommended total gain from pre-pregnancy BMI (IOM 2009, ACOG), weekly rate, twin ranges and a weekly target.
- [Protein Calculator — How Much Protein a Day?](https://www.calculatepilot.com/health/protein-calculator.html): Free protein calculator: daily protein in grams from your weight and activity or life stage (RDA, 65+, athletes, pregnancy), per meal and in foods.
- [Steps to Calories Calculator — Distance & Time](https://www.calculatepilot.com/health/steps-to-calories-calculator.html): Free steps to calories calculator: turn your step count into distance, walking time and calories using stride length, weight and walking pace.
- [Target Heart Rate Calculator — Exercise Zones](https://www.calculatepilot.com/health/target-heart-rate-calculator.html): Free target heart rate calculator: moderate and vigorous zones from your age (AHA) or resting heart rate (Karvonen), plus 5 training zones.
- [TDEE Calculator — Total Daily Energy Expenditure](https://www.calculatepilot.com/health/tdee-calculator.html): Free TDEE calculator: calories you burn per day from four BMR formulas and your activity level, plus goal calories and macro targets per meal.
- [VO2 Max Calculator — Estimate Aerobic Fitness](https://www.calculatepilot.com/health/vo2max-calculator.html): Free VO2 max calculator: estimate aerobic fitness from resting heart rate, the Rockport walk, Cooper 12-minute run or 1.5-mile run, in METs too.
- [Waist-to-Height Ratio Calculator — NICE Categories](https://www.calculatepilot.com/health/waist-to-height-ratio-calculator.html): Free waist-to-height ratio calculator: get your WHtR, the NICE central adiposity category (0.4–0.49 healthy), and the waist size that keeps it under 0.5.
- [Waist-to-Hip Ratio Calculator — WHO Thresholds](https://www.calculatepilot.com/health/waist-to-hip-ratio-calculator.html): Free waist-to-hip ratio calculator: get your WHR, compare it with the WHO cut-offs (0.90 men, 0.85 women), and check your waist circumference risk level.
- [Water Intake Calculator — Daily Fluid Needs](https://www.calculatepilot.com/health/water-intake-calculator.html): Free water intake calculator: daily fluid needs from National Academies and EFSA references by age, sex and pregnancy, plus extra water for exercise.
- [Weight Loss Calorie Calculator — Deficit Planner](https://www.calculatepilot.com/health/weight-loss-calorie-calculator.html): Free weight loss calorie calculator: turn your TDEE into a daily calorie target by weekly rate or goal date, compare rates, and check safety floors.

## Math calculators (40)

- [Area Calculator - 11 Shapes, Units & Steps](https://www.calculatepilot.com/math/area-calculator.html): Free area calculator for rectangles, triangles, circles, sectors, trapezoids, ellipses, polygons and coordinates, with unit conversion and steps.
- [Basic Calculator - Arithmetic with Memory & History](https://www.calculatepilot.com/math/basic-calculator.html): A simple calculator for everyday addition, subtraction, multiplication and division, with percentages, square roots, a memory register and a history tape.
- [Binary Calculator - Arithmetic, Bitwise & Two's Complement](https://www.calculatepilot.com/math/binary-calculator.html): Add, subtract, multiply or divide binary numbers, apply bitwise logic, shift or rotate bits, or convert to two's complement at 8 to 64-bit width.
- [Binomial Probability Calculator with Steps](https://www.calculatepilot.com/math/binomial-probability-calculator.html): Free binomial probability calculator: exact P(X = k), P(X ≤ k), P(X ≥ k), mean, variance and a PMF histogram for n up to 1,000, with steps.
- [Circle Calculator - Area, Circumference & Sector](https://www.calculatepilot.com/math/circle-calculator.html): Free circle calculator: radius, diameter, circumference and area from any one value, plus sector, arc, chord, segment and annulus, with steps.
- [Complex Number Calculator - Arithmetic, Polar & Roots](https://www.calculatepilot.com/math/complex-number-calculator.html): Add, subtract, multiply or divide complex numbers, find modulus, argument and polar form, or compute powers and roots with De Moivre's theorem.
- [3D Distance Calculator - Points, Plane & Vector](https://www.calculatepilot.com/math/distance-3d-calculator.html): Free 3D distance calculator: distance between two points, point-to-plane distance, vector length and bounding box, with midpoint and exact radicals.
- [Exponent Calculator - Powers, Roots & Notation](https://www.calculatepilot.com/math/exponent-calculator.html): Free exponent calculator: powers with negative and fractional exponents, nth roots, scientific notation and exponential growth or decay, with steps.
- [Factorial Calculator - n!, Double & Gamma](https://www.calculatepilot.com/math/factorial-calculator.html): Free factorial calculator: exact n! up to 3,000, double and multifactorials, subfactorials, Gamma function, trailing zeros and prime factors.
- [Fraction Calculator with Steps & Mixed Numbers](https://www.calculatepilot.com/math/fraction-calculator.html): Free fraction calculator: add, subtract, multiply, divide and simplify fractions and mixed numbers with exact answers, decimals and steps.
- [GCD & LCM Calculator with Euclid Steps](https://www.calculatepilot.com/math/gcd-lcm-calculator.html): Free GCD and LCM calculator: greatest common divisor and least common multiple of two numbers or a list, with Euclid steps, prime factors and Bezout.
- [Log Calculator - log, ln, log2 & Change of Base](https://www.calculatepilot.com/math/log-calculator.html): Free log calculator: log base 10, natural log, log base 2 and any base, antilogs, characteristic and mantissa, with change-of-base steps and a graph.
- [Matrix Calculator (2x2) - Determinant, Inverse & Eigenvalues](https://www.calculatepilot.com/math/matrix-calculator.html): Find a 2x2 matrix's determinant, inverse, trace and eigenvalues, multiply two matrices, or solve Ax = b with Cramer's rule. Free, with full working shown.
- [Mean, Median & Mode Calculator with Steps](https://www.calculatepilot.com/math/mean-median-mode-calculator.html): Free mean, median and mode calculator: every mode, plus geometric and harmonic means, trimmed mean, range and skewness, with sorted list and steps.
- [Modulo Calculator - Mod, Congruence & Modular Inverse](https://www.calculatepilot.com/math/modulo-calculator.html): Compute a mod n with the correct sign, check a congruence, find a modular inverse, or compute aᵇ mod n exactly for huge exponents. Free, with full steps.
- [Number Base Converter - Binary, Hex, Octal & More](https://www.calculatepilot.com/math/number-base-converter.html): Convert a whole or fractional number between any two bases from 2 to 36, with a quick-reference row for binary, octal, decimal and hex. Free, with full steps.
- [Number to Words Converter - Cardinal, Ordinal & Check](https://www.calculatepilot.com/math/number-to-words-calculator.html): Spell out a number as cardinal words, an ordinal, a currency amount, or a legal check line, in short (US) or long (European) scale. Free, with full steps.
- [Percent Error Calculator with Steps & Tolerance](https://www.calculatepilot.com/math/percent-error-calculator.html): Free percent error calculator: percent error, absolute and relative error, direction of bias, percent difference and a tolerance check, with steps.
- [Percentage Calculator - % of, % Change & Reverse](https://www.calculatepilot.com/math/percentage-calculator.html): Free percentage calculator: P% of X, X is what % of Y, percentage change and reverse percentages, with fractions, multipliers and steps.
- [Permutation & Combination Calculator (nPr, nCr)](https://www.calculatepilot.com/math/permutation-combination-calculator.html): Free nPr and nCr calculator: exact permutations and combinations with or without repetition for n up to 1,000, with factorial steps.
- [Polynomial Calculator - Division, Roots & Factoring](https://www.calculatepilot.com/math/polynomial-calculator.html): Divide polynomials with synthetic division, find real and complex roots, factor, add/subtract/multiply, or evaluate with Horner's method. Free, with full steps.
- [Prime Number Checker - Primality, Factors & Mersenne](https://www.calculatepilot.com/math/prime-number-checker.html): Check if a number is prime, see its factorization, sieve primes in a range, or test a Mersenne number 2^p-1 with the Lucas-Lehmer test. Free, with full steps.
- [Probability Calculator - Events, Bayes & Odds](https://www.calculatepilot.com/math/probability-calculator.html): Free probability calculator: two or three events, independent or mutually exclusive, Bayes' theorem and odds, with a Venn diagram and full steps.
- [Pythagorean Theorem Calculator - Hypotenuse & Leg](https://www.calculatepilot.com/math/pythagorean-theorem-calculator.html): Free Pythagorean theorem calculator: hypotenuse, missing leg, 3D distance and triple checker, with exact radicals, angles and steps.
- [Quadratic Formula Calculator - Roots & Vertex](https://www.calculatepilot.com/math/quadratic-formula-calculator.html): Free quadratic formula calculator: real and complex roots, discriminant, exact radicals, vertex, focus, factored form and a graph, with full steps.
- [Quartile & IQR Calculator with Outlier Fences](https://www.calculatepilot.com/math/quartile-calculator.html): Free quartile calculator: Q1, median, Q3, IQR and Tukey outlier fences for a data set, with a box plot and four quartile methods compared.
- [Random Number Generator - Integers, Floats & Gaussian](https://www.calculatepilot.com/math/random-number-generator.html): Generate uniform random integers or decimals, normally-distributed values, or a reproducible seeded sequence, using your browser's secure random source. Free.
- [Ratio Calculator - Simplify, Solve & Scale](https://www.calculatepilot.com/math/ratio-calculator.html): Free ratio calculator: simplify ratios, solve a missing proportion term, scale a ratio or split a total across parts, with Euclid's algorithm steps.
- [Scientific Calculator - Trig, Logs, Powers & PEMDAS](https://www.calculatepilot.com/math/scientific-calculator.html): Type an expression with trig functions, logarithms, powers, roots and parentheses, evaluated with correct order of operations (PEMDAS), in degrees or radians.
- [Scientific Notation Calculator - Convert & Compute](https://www.calculatepilot.com/math/scientific-notation-calculator.html): Convert a decimal to scientific, engineering, e-notation and SI prefix form, convert back to decimal, or multiply/divide in scientific notation.
- [Sequence Calculator - Arithmetic, Geometric & Fibonacci](https://www.calculatepilot.com/math/sequence-calculator.html): Find the nth term and sum of an arithmetic or geometric sequence, compute exact Fibonacci or Lucas numbers, or solve a custom recurrence. Free, with full steps.
- [Significant Figures Calculator - Count & Round](https://www.calculatepilot.com/math/sig-fig-calculator.html): Count the significant figures in a number, classify each digit, round with half-to-even rounding, or apply sig-fig rules to addition and multiplication.
- [Slope Calculator - Slope, Angle, Grade & Equation](https://www.calculatepilot.com/math/slope-calculator.html): Free slope calculator: slope from two points, a point and slope, an angle or Ax + By = C, with grade, angle, pitch, intercepts and line equations.
- [Standard Deviation Calculator with Steps](https://www.calculatepilot.com/math/standard-deviation-calculator.html): Free standard deviation calculator: sample or population SD, variance, mean, sum of squares, CV and a 95% CI for the mean, with full steps.
- [Triangle Calculator - SSS, SAS, ASA, AAS, SSA](https://www.calculatepilot.com/math/triangle-calculator.html): Free triangle calculator: solve SSS, SAS, ASA, AAS and ambiguous SSA triangles for all sides, angles, area, inradius and circumradius, with steps.
- [Trigonometry Calculator - Sin, Cos, Tan & Inverse](https://www.calculatepilot.com/math/trigonometry-calculator.html): Free trigonometry calculator: all six functions with exact values, inverse and hyperbolic functions, the unit circle and a right-triangle solver.
- [Vector Calculator - Dot, Cross Product & Angle](https://www.calculatepilot.com/math/vector-calculator.html): Free vector calculator: dot product, cross product, angle, magnitude, unit vector and projection for 2D and 3D vectors, with the working shown.
- [Volume Calculator - 12 Solids & Capacity Units](https://www.calculatepilot.com/math/volume-calculator.html): Free volume calculator for cubes, boxes, cylinders, spheres, cones, pyramids, capsules, ellipsoids and tori, with surface area and litre/gallon conversion.
- [Weighted Average Calculator with Steps](https://www.calculatepilot.com/math/weighted-average-calculator.html): Free weighted average calculator: enter values and weights (percent, credits, dollars) for the weighted mean, weight shares, impact and full steps.
- [Z-Score Calculator - Percentile, Tails & Steps](https://www.calculatepilot.com/math/z-score-calculator.html): Free z-score calculator: z-score, percentile and tail probabilities from a mean and SD, a raw data set or a percentile, with full steps.

## Everyday calculators (45)

- [Age Calculator: Exact Age in Years, Months and Days](https://www.calculatepilot.com/other/age-calculator.html): Free age calculator: exact age in years, months and days, total days and hours lived, next birthday, milestone days, zodiac signs and life progress.
- [Base64 Encoder and Decoder: Text and Hex Online](https://www.calculatepilot.com/other/base64-encode-decode.html): Free Base64 encoder and decoder: convert text or hex to Base64 and back, with URL-safe Base64url, padding control, MIME line wrapping and a bit-level view.
- [Break-Even Calculator: Units, Revenue and Profit](https://www.calculatepilot.com/other/break-even-calculator.html): Free break-even calculator: units and revenue to cover fixed and variable costs, target profit volume, margin of safety, operating leverage and margin vs markup.
- [Car Depreciation Calculator: Value and 5-Year Cost](https://www.calculatepilot.com/other/car-depreciation-calculator.html): Free car depreciation calculator: estimated resale value each year, loan interest and total cost of ownership with insurance, maintenance and fuel.
- [Driving Carbon Footprint Calculator: CO2 From Your Car](https://www.calculatepilot.com/other/carbon-footprint-calculator.html): Free driving carbon footprint calculator: CO2 from gasoline, diesel, hybrid or electric driving for a year or a trip, with tree seedling equivalent, offset cost and comparison.
- [Commute Cost Calculator: Drive vs Transit vs Remote](https://www.calculatepilot.com/other/commute-cost-calculator.html): Free commute cost calculator: monthly and yearly cost of driving to work including fuel, wear, tolls, parking and time, compared with transit, rideshare and remote days.
- [Concrete Calculator: Cubic Yards and Bags Needed](https://www.calculatepilot.com/other/concrete-calculator.html): Free concrete calculator for slabs, footings, round columns and steps: cubic yards, weight, 80/60/50 lb bags and a ready-mix cost comparison.
- [Length Converter: mm, cm, m, km, Inches, Feet, Miles](https://www.calculatepilot.com/other/conversion-calculator.html): Free length converter for metric and imperial units with exact factors, every unit at once and a tape-measure fraction of an inch.
- [Date Calculator: Days Between Dates and Business Days](https://www.calculatepilot.com/other/date-calculator.html): Free date calculator: days between two dates, add or subtract days, and count business days skipping weekends, US, UK, Canada or Australia holidays.
- [Density Calculator: Mass, Volume and Density](https://www.calculatepilot.com/other/density-calculator.html): Free density calculator: solve mass, volume or density for 40 common materials in metric and imperial units, with specific gravity, float or sink and infill percentage.
- [Dice Roller: Roll Any Dice Expression With Exact Odds](https://www.calculatepilot.com/other/dice-roller.html): Free online dice roller: roll d4 to d100, 4d6kh3, advantage and more with keep or drop rules, exploding dice and exact probability for every total.
- [Dog Food Calculator: Daily Cups and Calories](https://www.calculatepilot.com/other/dog-food-portion-calculator.html): Free dog food calculator: daily calories (RER and DER), cups per day and per meal, treat allowance and how long a bag lasts, by weight, life stage and body condition.
- [Electricity Cost Calculator: Appliance Running Cost](https://www.calculatepilot.com/other/electricity-cost-calculator.html): Free electricity cost calculator: what any appliance costs per hour, day, month and year from watts, hours and your kWh rate, with carbon output and a ledger.
- [Flight Time Calculator: Duration, Distance and Jet Lag](https://www.calculatepilot.com/other/flight-time-calculator.html): Free flight time calculator: great-circle distance, gate-to-gate time with wind, local arrival time and jet lag between 40 major airports.
- [Fuel Cost Calculator: Trip Gas Cost by Distance and MPG](https://www.calculatepilot.com/other/fuel-cost-calculator.html): Calculate what a trip will cost in fuel from distance, MPG or L/100 km and fuel price. Round trip, passenger split, vehicle presets and class comparison. Free.
- [Gas Mileage Calculator: MPG and Trip Fuel Cost](https://www.calculatepilot.com/other/gas-mileage-calculator.html): Free gas mileage calculator: find your MPG from a fill-up or price a trip, with gallons, litres, cost per mile, passenger split, CO₂ and an EV comparison.
- [Golf Handicap Calculator: Index and Course Handicap](https://www.calculatepilot.com/other/golf-handicap-calculator.html): Free golf handicap calculator using the World Handicap System: score differentials, Handicap Index from your best rounds, Course Handicap and Playing Handicap.
- [GPA Calculator: Semester and Cumulative GPA](https://www.calculatepilot.com/other/gpa-calculator.html): Free GPA calculator: semester and cumulative GPA on 4.0, 4.33 and 5.0 weighted scales, with prior credits, grade distribution and a final exam grade solver.
- [Final Grade Calculator: Score Needed on Your Final](https://www.calculatepilot.com/other/grade-needed-calculator.html): Free final grade calculator: the score you need on your final exam to reach a target grade, in percent and points, with the score needed for each letter grade.
- [Gravel Calculator: Cubic Yards, Tons and Bags](https://www.calculatepilot.com/other/gravel-calculator.html): Free gravel calculator for driveways, paths and beds: cubic yards, tons with compaction allowance, 50 lb bags and a bulk delivery versus bag cost comparison.
- [Child Height Predictor: Adult Height Calculator](https://www.calculatepilot.com/other/height-calculator.html): Free child adult height predictor: mid-parental (Tanner) target height with range, plus a growth channel estimate and typical height by age for boys and girls.
- [Hours Calculator: Work Hours, Overtime and Pay](https://www.calculatepilot.com/other/hours-calculator.html): Free hours calculator: timecard totals with unpaid meals, overnight shifts, overtime rules, 7-minute rounding, gross pay and take-home estimate.
- [Invoice Late Fee Calculator: Interest on Overdue Invoices](https://www.calculatepilot.com/other/invoice-late-fee-calculator.html): Free invoice late fee calculator: interest on an overdue invoice with grace period, flat fee, simple or compound interest, daily charge and ageing bucket.
- [Love Calculator: Name Match, FLAMES and Love Languages](https://www.calculatepilot.com/other/love-calculator.html): Free love calculator for fun: a love percentage from two names, the FLAMES game and love language tips. An entertainment game, not a real measure of compatibility.
- [Board Foot Calculator: Lumber Volume and Cost](https://www.calculatepilot.com/other/lumber-board-feet-calculator.html): Free board foot calculator for hardwood and softwood: board feet, waste allowance, linear feet, cubic volume, price and a multi-board cut list.
- [Markup and Margin Calculator: Margin to Markup](https://www.calculatepilot.com/other/markup-margin-calculator.html): Free markup and margin calculator: convert between gross margin and markup, find selling price and profit, and check your break-even volume.
- [Moving Cost Estimator: Movers vs Container vs DIY](https://www.calculatepilot.com/other/moving-cost-estimator.html): Free moving cost estimator: compare full-service movers, a moving container and a rental truck by distance, weight, season and services.
- [Mulch Calculator: Cubic Yards, Bags and Weight](https://www.calculatepilot.com/other/mulch-calculator.html): Free mulch, compost and topsoil calculator: cubic yards, bags of 1.5, 2 and 3 cu ft, weight and a bulk versus bagged cost check for garden beds.
- [Paint Calculator: How Much Paint Do I Need?](https://www.calculatepilot.com/other/paint-calculator.html): Free paint calculator: gallons and quarts for walls, ceiling and trim after doors and windows, with texture, coats, 10% waste and a shopping list.
- [Password Generator: Strong Random Passwords and Passphrases](https://www.calculatepilot.com/other/password-generator.html): Free secure password generator: random passwords, passphrases and PINs made in your browser, with entropy in bits and time-to-guess estimates. Nothing is sent or stored.
- [Pet Age Calculator: Dog and Cat Age in Human Years](https://www.calculatepilot.com/other/pet-age-calculator.html): Free pet age calculator: dog and cat age in human years using size-based veterinary tables or the UCSD epigenetic clock, with life stage and care timing.
- [Recipe Converter: Scale Servings and Cooking Units](https://www.calculatepilot.com/other/recipe-conversion-calculator.html): Free recipe scaler and kitchen converter: scale servings, see grams and baker's percentages, and convert cups, spoons, ounces and grams by ingredient.
- [Roman Numeral Converter: Numbers, Dates and Large Values](https://www.calculatepilot.com/other/roman-numeral-converter.html): Free Roman numeral converter: numbers to Roman numerals and back up to 3,999,999, standard or additive style, and dates in Roman numerals.
- [Shipping Cost Calculator: Dimensional Weight](https://www.calculatepilot.com/other/shipping-cost-calculator.html): Free shipping cost calculator: dimensional weight vs actual weight, billable weight, zone by distance and cost at your carrier rates, with box-size savings.
- [Sleep Calculator: Best Bedtime and Wake Time](https://www.calculatepilot.com/other/sleep-calculator.html): Free sleep calculator: find the best bedtime or wake-up time from 90-minute sleep cycles, allowing for how long you take to fall asleep, plus nap lengths.
- [Speed Calculator: Speed, Pace and Travel Time](https://www.calculatepilot.com/other/speed-calculator.html): Free speed calculator: find speed, running pace, travel time or distance in mph, km/h, m/s and knots, with split times for 5K, 10K, half marathon and marathon.
- [Square Footage Calculator: Room and Shape Area](https://www.calculatepilot.com/other/square-footage-calculator.html): Free square footage calculator: area of rooms, triangles and circles in feet and inches or metres, with waste margin, sq yd, m² and a multi-room ledger.
- [Tile Calculator: Tiles, Grout and Thin-Set Needed](https://www.calculatepilot.com/other/tile-calculator.html): Free tile calculator: how many tiles and boxes to buy with waste for your layout, plus grout weight, thin-set bags and a material cost estimate.
- [Time Calculator: Duration, Add and Subtract Time](https://www.calculatepilot.com/other/time-calculator.html): Free time calculator: hours and minutes between two clock times (overnight too), add or subtract time, add up durations and convert to decimal hours.
- [Tip Calculator: Split the Bill and Tip Fairly](https://www.calculatepilot.com/other/tip-calculator.html): Free tip and split bill calculator: tip on the pre-tax subtotal, sales tax, equal or weighted split and exact-cent shares that add up to the total.
- [Unit Price Calculator: Compare Grocery Prices](https://www.calculatepilot.com/other/unit-price-calculator.html): Free unit price calculator: compare up to six products by price per ounce, pound, litre or sheet, convert mixed units and check for shrinkflation.
- [URL Encoder and Decoder: Percent-Encoding Online](https://www.calculatepilot.com/other/url-encode-decode.html): Free URL encoder and decoder: percent-encode a component or full URL, decode %20 sequences, choose + or %20 for spaces and see every query parameter.
- [UTC Time Converter: Zulu Time and World Clock](https://www.calculatepilot.com/other/utc-time-converter.html): Free UTC time converter: convert any time to UTC, Zulu, ISO 8601, Unix time and Julian day, and see the same moment in major cities with daylight saving handled.
- [Wedding Budget Calculator: Category Split and Payment Plan](https://www.calculatepilot.com/other/wedding-budget-calculator.html): Free wedding budget calculator: hold back a contingency, split your budget across venue, photography, flowers, music and attire, see cost per guest and a vendor payment schedule.
- [Word Counter: Words, Characters and Readability](https://www.calculatepilot.com/other/word-counter.html): Free word counter and readability analyzer: words, characters, sentences, reading time, Flesch scores, keyword density and social media length limits.

## Guides and explainers (56)

- [529 Calculator by Age: How Much Should You Save?](https://www.calculatepilot.com/guides/529-calculator-by-age-guide.html): Use a 529 calculator by age to estimate college savings growth, monthly contributions, future college costs, and funding gaps. Includes examples for different ages.
- [529 College Savings Calculator: Growth, Contributions & Examples](https://www.calculatepilot.com/guides/529-college-savings-calculator-guide.html): Learn how a 529 college savings calculator estimates future value, monthly contributions, growth and college funding targets with practical examples.
- [BMI Calculator Guide: What Your Number Really Means](https://www.calculatepilot.com/guides/bmi-calculator-guide.html): A practical guide to BMI — what it measures, how to calculate it, who it misleads, and which other health metrics to track alongside it.
- [Car Depreciation Chart 2026 — How Much Does a Car Lose Value?](https://www.calculatepilot.com/guides/car-depreciation-guide.html): Car depreciation chart 2026: new cars lose 20-30% in year one, 15-20% per year after. Full breakdown by year, make, and model type. Free depreciation calculator.
- [Car Loan Refinance Calculator Guide: Check If Refinancing Saves Money](https://www.calculatepilot.com/guides/car-loan-refinance-calculator-guide.html): Learn how to use a car loan refinance calculator: gather your payoff balance and rate, compare a new offer, and read monthly savings versus total interest before you refinance.
- [Cos Inverse -1 = 180° | arccos(-1) Explained](https://www.calculatepilot.com/guides/cos-inverse-minus-one.html): Find cos inverse of -1 instantly: arccos(-1) = 180° = π radians. Learn why, see the unit-circle explanation, degree/radian forms, and use the trigonometry calculator.
- [Debt Avalanche vs. Snowball: Real Numbers on $14,700 in Debt (2026)](https://www.calculatepilot.com/guides/debt-payoff-avalanche-vs-snowball-real-numbers.html): Avalanche vs snowball with an actual worked example: three real debts, exact months, exact interest saved. Plus the 0% balance transfer breakeven math.
- [Debt Payoff Calculator Guide: How Payment Changes Your Debt-Free Date](https://www.calculatepilot.com/guides/debt-payoff-calculator-guide.html): Learn how payment size, interest rate, and balance change your debt-free date. Use the CalculatePilot Debt Payoff Calculator to compare realistic payoff strategies and interest costs.
- [Discount Calculator Guide: Calculate Sale Price & Savings](https://www.calculatepilot.com/guides/discount-calculator-guide.html): Learn how to calculate discounts, sale prices, and savings with simple percentage formulas and examples. Includes discount plus tax and reverse discount examples.
- [Emergency Fund Calculator Guide: Build a Cash Reserve That Fits Your Real Life](https://www.calculatepilot.com/guides/emergency-fund-calculator-guide.html): Use an emergency fund calculator to set a practical savings target based on essential expenses, income stability, dependents, and unexpected costs.
- [Height Calculator Guide: Feet, Inches & CM Conversion](https://www.calculatepilot.com/guides/height-calculator-guide.html): Learn how to convert height between feet, inches, centimeters, and meters with simple formulas, examples, and a height conversion table.
- [How to Calculate a Mortgage Payment: Formula, Example & Amortization](https://www.calculatepilot.com/guides/how-to-calculate-mortgage-payment.html): Learn how to calculate a mortgage payment step by step: the formula, a worked $240,000 example, an amortization schedule, and how rate, term and down payment change your cost.
- [Monthly Mortgage Formula Explained Simply](https://www.calculatepilot.com/guides/monthly-mortgage-formula-explained-simply.html): Learn the monthly mortgage formula M = P[r(1+r)^n]/[(1+r)^n-1]. Worked $300,000 example, Excel PMT, taxes, PMI, and amortization.
- [Mortgage Calculator Guide: Estimate Payments, Interest & Affordability](https://www.calculatepilot.com/guides/mortgage-calculator-guide.html): Learn how to use a mortgage calculator to estimate monthly payments, total interest, loan affordability, down payments, taxes, insurance, and the effect of extra payments.
- [Extra Mortgage Payments vs. Investing: The Real Math (2026)](https://www.calculatepilot.com/guides/mortgage-extra-payments-vs-investing.html): Should you pay extra on your mortgage or invest the difference? Worked numbers on a $400,000 loan, biweekly payment savings, PMI removal timing, and points breakeven math.
- [How Much Does It Cost to Hire Movers? 2026 Moving Cost Guide](https://www.calculatepilot.com/guides/moving-cost-guide.html): Moving costs in 2026: local moves average $800–$2,500, long-distance $2,000–$7,500+. Full breakdown by home size, distance, and service type.
- [Number to Words Converter: How to Spell Numbers in Words](https://www.calculatepilot.com/guides/number-to-words-guide.html): Learn how to convert numbers to words for checks, forms, invoices, and documents. See examples, rules, and common mistakes with a free number to words converter.
- [How to Calculate Percentages — Complete Guide with Examples](https://www.calculatepilot.com/guides/percentage-guide.html): How to calculate percentages: find X% of a number, percentage increase/decrease, and what percentage one number is of another. Formula and worked examples.
- [SAVE Plan Borrowers Face a Deadline This Month — What It Means for Your Payment](https://www.calculatepilot.com/guides/save-plan-deadline-student-loan-payments-2026.html): A SAVE repayment plan deadline this month could raise monthly payments for federal student loan borrowers who don't switch plans in time. Here's what's happening and what to do.
- [Scientific Notation Calculator Guide: Convert Decimals & Scientific Form](https://www.calculatepilot.com/guides/scientific-notation-guide.html): Learn how to convert decimals to scientific notation and back. Understand coefficients, positive and negative exponents, formulas, and worked examples.
- [Slope Calculator Guide: Formula & Slope Between Two Points](https://www.calculatepilot.com/guides/slope-calculator-guide.html): Learn how to calculate slope between two points using the slope formula. Covers positive, negative, zero, and undefined slopes with examples.
- [How to Calculate Student Loan Payments — 2026 Complete Guide](https://www.calculatepilot.com/guides/student-loan-guide.html): Student loan payment formula explained. A $30,000 loan at 6.5% over 10 years = $340/month. Full breakdown by loan amount, rate, and term with payment tables.
- [How to Find Angles of a Triangle (With Side Lengths)](https://www.calculatepilot.com/guides/triangle-calculator-guide.html): How to find the angles of a triangle from side lengths using the Law of Cosines. Includes base angles, area formulas, triangle inequality, and a worked 5-6-7 example.
- [UTC Time Converter Guide: Convert UTC to Local Time](https://www.calculatepilot.com/guides/utc-time-converter-guide.html): Learn how UTC works, how to convert UTC to local time, calculate UTC offsets, and understand the difference between UTC and GMT.
- [VA Home Loan Calculator Guide: Funding Fee, Taxes & Monthly Payment](https://www.calculatepilot.com/guides/va-home-loan-calculator-guide.html): Learn how to calculate a VA home loan payment, including the VA funding fee, taxes, and insurance. See sample payments by home price and how down payment changes the fee.
- [Volume Calculator Guide: Formulas for Common Shapes](https://www.calculatepilot.com/guides/volume-calculator-guide.html): Learn volume formulas for cubes, rectangular boxes, cylinders, spheres, cones, and other shapes with simple worked examples.
- [How to Calculate Compound Interest — Formula & Examples](https://www.calculatepilot.com/how-to-calculate-compound-interest.html): Compound interest formula explained: A = P(1 + r/n)^(nt). Learn how to calculate compound interest with worked examples for savings, investments, and loans.
- [What Is a Good BMI? BMI Ranges Explained](https://www.calculatepilot.com/what-is-a-good-bmi.html): A healthy BMI is 18.5 to 24.9. Learn what BMI means, how it is calculated, what the different ranges indicate, and its limitations as a health measure.
- [What Is a Good Debt-to-Income Ratio?](https://www.calculatepilot.com/what-is-a-good-debt-to-income-ratio.html): A good DTI ratio is below 36%. Learn what debt-to-income ratio means, how to calculate front-end and back-end DTI, and what lenders actually look for.
- [How Long to Pay Off $5,000 Credit Card Debt? Payment Chart](https://www.calculatepilot.com/guides/how-long-to-pay-off-5000-credit-card-debt.html): $5,000 at 22% APR takes 34 months at $200 a month and costs about $1,750 in interest. See payoff times for $100 to $500 payments.
- [CD vs High-Yield Savings Account: Which Earns More?](https://www.calculatepilot.com/guides/cd-vs-high-yield-savings-account.html): A locked 4.50% CD earns $450.00 on $10,000 in a year; a savings account earns more only if its rate stays at or above the CD's. See the comparison and break-even rule.
- [How Many Steps Burn 100 Calories? Chart by Weight & Pace](https://www.calculatepilot.com/guides/how-many-steps-to-burn-100-calories.html): About 2,410 steps burn 100 calories for a 160 lb adult at a moderate pace. See the chart by body weight and walking speed, plus the formula.
- [How Much Weight Should I Gain in Pregnancy? Chart by Week](https://www.calculatepilot.com/guides/how-much-weight-should-i-gain-during-pregnancy-by-week.html): Recommended pregnancy weight gain by pre-pregnancy BMI: 25-35 lb total for normal weight, about 7-12 lb by week 20. IOM chart by week and BMI category.
- [What Grade Do I Need on My Final Exam? Formula & Examples](https://www.calculatepilot.com/guides/what-grade-do-i-need-on-my-final-exam.html): Find the score you need on your final to reach your target grade. Formula, tables and worked examples, e.g. 82% going into a 30% final needs 92% for an 85%.
- [How Long Does It Take to Save $10,000? Monthly Plan Chart](https://www.calculatepilot.com/guides/how-long-to-save-10000-dollars.html): Saving $500 a month reaches $10,000 in 20 months. See how long it takes at other monthly deposits, and the deposit needed for any deadline.
- [How Much Down Payment Do You Need for a $400,000 House?](https://www.calculatepilot.com/guides/down-payment-on-400000-house.html): 20% down on a $400,000 house is $80,000; 3% is $12,000. See the loan, PMI and monthly payment at 3%, 5%, 10% and 20% down.
- [How Many Months of Expenses Should an Emergency Fund Cover?](https://www.calculatepilot.com/guides/how-many-months-emergency-fund.html): Most guidance suggests 3-6 months of essential expenses: $10,500-$21,000 on $3,500 a month. See targets by situation and a worked example.
- [How Long Does It Take to Break Even on a Refinance?](https://www.calculatepilot.com/guides/refinance-break-even-how-long.html): Divide closing costs by monthly savings: $6,000 of costs and $197 saved a month breaks even in about 30 months. Table by closing costs and rate drop.
- [How Many Calories to Eat to Lose 1 Pound a Week?](https://www.calculatepilot.com/guides/calories-to-lose-one-pound-a-week.html): Eat about 500 calories below your maintenance level to lose roughly 1 pound a week. See daily targets by TDEE and weekly rate, with a worked example.
- [Car Depreciation Chart: Value by Year & How to Calculate It](https://www.calculatepilot.com/guides/car-depreciation-chart-guide.html): Understand car depreciation by year with a clear value-retention chart, depreciation formula, worked example, and factors such as mileage, condition.
- [Moving Cost Calculator: Estimate Your Moving Costs](https://www.calculatepilot.com/guides/moving-cost-calculator-guide.html): Learn how to estimate moving costs by home size, distance, labor, packing, storage and other expenses with a practical moving cost calculator guide.
- [Percentage Calculator: Percent, Increase](https://www.calculatepilot.com/guides/percentage-calculator-guide.html): Learn how to calculate percentages, percentage increase and decrease, and find what percent one number is of another with worked examples.
- [How Much Rent Can I Afford? 30% Rule by Salary](https://www.calculatepilot.com/guides/how-much-rent-can-i-afford.html): Spend no more than about 30% of gross income on rent: $1,500 a month on a $60,000 salary. See rent by salary, the 40x landlord rule and hidden costs.
- [How Much Do I Need to Retire? The 25x Rule Explained](https://www.calculatepilot.com/guides/how-much-do-i-need-to-retire-25x-rule.html): Save 25 times your annual spending: $72,000 a year needs about $1,800,000 at a 4% withdrawal rate. See the table, where the rule comes from and its limits.
- [How Much House Can I Afford on a $75,000 Salary?](https://www.calculatepilot.com/guides/how-much-house-can-i-afford-on-75000-salary.html): The 28/36 rule suggests about $272,000 on a $75,000 salary with 20% down and no other debts. See the table by salary and a worked example.
- [How to Calculate Your Due Date: LMP, Conception & IVF](https://www.calculatepilot.com/guides/how-to-calculate-your-due-date.html): Add 280 days to the first day of your last period: 1 March 2026 gives 6 December 2026. Adjust for cycle length, or use conception (+266 days) or IVF dating.
- [How Much Protein Do I Need Per Day? Chart by Weight](https://www.calculatepilot.com/guides/how-much-protein-do-i-need-per-day.html): Multiply weight in kg by 0.8-2.2 depending on activity: an 82 kg moderately active adult needs about 98-131 g a day. Chart by weight and activity.
- [How to Calculate Your TDEE: Formula and Worked Examples](https://www.calculatepilot.com/guides/how-to-calculate-tdee.html): TDEE = BMR x an activity multiplier of 1.2 to 1.9. A 40-year-old woman, 70 kg, 165 cm, moderately active has a BMR of about 1,370 and a TDEE of about 2,124 calories a day.
- [BMR vs TDEE: What Is the Difference?](https://www.calculatepilot.com/guides/bmr-vs-tdee-difference.html): BMR is calories burned at rest; TDEE adds digestion and movement. In the worked example BMR is about 65% of a 2,124 calorie TDEE.
- [How Many Calories Should I Eat a Day? Chart by Age and Sex](https://www.calculatepilot.com/guides/how-many-calories-should-i-eat-a-day.html): Most adults need about 1,600 to 3,000 calories a day; estimated needs by age, sex and activity from the Dietary Guidelines for Americans, plus how to calculate your own.
- [How Much Water Should I Drink a Day? Chart and Formula](https://www.calculatepilot.com/guides/how-much-water-should-i-drink-a-day.html): National Academies adequate intake is about 2.7 L (women) and 3.7 L (men) of total water; about 80% from drinks, roughly 9 and 13 cups, plus more for exercise.
- [Healthy Body Fat Percentage by Age and Sex (Chart)](https://www.calculatepilot.com/guides/healthy-body-fat-percentage-by-age-and-sex.html): Healthy body fat is about 21-32% for women and 8-19% for men aged 20-39; ACE categories, the Navy method and a worked example (90 cm waist, 38 cm neck, 178 cm: about 20%).
- [Waist-to-Height Ratio Chart: Healthy Range and How to Measure](https://www.calculatepilot.com/guides/waist-to-height-ratio-chart.html): Keep your waist below half your height; NICE categories 0.4-0.49 healthy, 0.5-0.59 increased, 0.6+ high. Example: 95 cm waist at 170 cm gives 0.56.
- [Target Heart Rate by Age: Chart and Zones for Exercise](https://www.calculatepilot.com/guides/target-heart-rate-by-age-chart.html): Max heart rate about 220 minus age; moderate 50-70% and vigorous 70-85%. A 45-year-old has a moderate zone of about 88-123 bpm. Includes the Karvonen method.
- [Epley vs Brzycki: One Rep Max Formulas Compared](https://www.calculatepilot.com/guides/epley-vs-brzycki-one-rep-max-formulas.html): Epley: w x (1 + reps/30); Brzycki: w x 36/(37 - reps). 155 lb for 8 reps is about 196 lb (Epley) and 192 lb (Brzycki); comparison table for 100 kg.
- [Macro Split for Fat Loss: Ratios, Grams and Examples](https://www.calculatepilot.com/guides/macro-split-for-fat-loss.html): Compare 30/30/40, 35/25/40, 40/30/30 and 25/30/45 at 2,400 calories in grams, with AMDR ranges (protein 10-35%, fat 20-35%, carbs 45-65%).

## Languages

English is the default. Translated versions of the calculators keep the same URLs under a language folder, and each page links its translations with hreflang.

- Spanish: https://www.calculatepilot.com/es/ (177 indexable pages), sitemap https://www.calculatepilot.com/es/sitemap.xml
- French: https://www.calculatepilot.com/fr/ (177 indexable pages), sitemap https://www.calculatepilot.com/fr/sitemap.xml
- German: https://www.calculatepilot.com/de/ (178 indexable pages), sitemap https://www.calculatepilot.com/de/sitemap.xml