Formula-Backed Mathematical Models

Financial Calculators

Mortgages, loans, tax, retirement and investing — 55 formula-backed tools, including UK repayment vs interest-only, UK overpayment, England & NI SDLT, Scotland LBTT, Wales LTT, UK student-loan PAYE, England/Wales/NI take-home pay, and Scottish take-home pay. None of those is a currency overlay of a US page.

55 formula-backed toolsClient-side precisionYour inputs never leave your browser

Mortgages & Property

16 tools
Seller Net Sheet CalculatorNet proceeds after commission and closing costs
1031 Exchange CalculatorCapital gains deferral, boot and 45/180-day deadlines
Mortgage CalculatorMonthly payments, amortization schedule, taxes, insurance and PMI
UK Mortgage Repayment CalculatorUKRepayment vs interest-only monthly comparisons
UK Mortgage Overpayment CalculatorUKInterest saved and years cut by overpaying
House Affordability CalculatorMaximum home price based on income and debt-to-income
Down Payment CalculatorDeposit targets and PMI thresholds
Refinance CalculatorBreak-even point and lifetime interest difference
Rental Yield CalculatorGross vs net rental yield after running costs
House Flip Profit CalculatorPurchase, rehab and holding costs vs sale profit
UK Stamp Duty CalculatorSDLTEngland & NI stamp duty for buyers, second homes and companies
UK Stamp Duty ComparisonEngland, Scotland and Wales property tax on one price
Scotland LBTT CalculatorScotlandLand and Buildings Transaction Tax with the 8% ADS
Wales LTT CalculatorWalesWelsh Land Transaction Tax main and higher rates
HELOC CalculatorHome equity line of credit draw and repayment phases
Rent CalculatorHow much rent you can afford on your income

Taxes & Take-Home Pay

7 tools
Income Tax CalculatorEstimate income tax from taxable income and brackets
UK Take-Home Pay CalculatorUK PAYEEngland, Wales & NI or Scottish tax, NI, pension and student loan
Scotland Take-Home Pay CalculatorScottish BandsSix Scottish income tax bands with UK National Insurance
Paycheck CalculatorNet pay per paycheck after withholding
Salary CalculatorConvert between hourly, weekly, monthly and annual pay
Sales Tax CalculatorAdd sales tax to a price or back it out
VAT CalculatorAdd or remove VAT at standard and reduced rates

Investing & Wealth

13 tools
CD vs HYSA CalculatorFixed CD rate vs variable high-yield savings
Compound Interest CalculatorGrowth with regular contributions and any compounding frequency
Investment CalculatorPortfolio growth with returns and contributions
401K CalculatorEmployer match, 2026 IRS limits and retirement balance
Roth IRA CalculatorTax-free growth, contribution limits and Roth vs Traditional
Retirement CalculatorFIRE number, safe withdrawal rate and portfolio longevity
Annuity CalculatorPayouts and present value of an income stream
Net Worth CalculatorAssets minus debts, compared with your age group
Bond Price CalculatorBond price, coupon and yield to maturity
CD CalculatorCertificate of deposit maturity value and APY
529 College Savings CalculatorCollege cost projection and monthly savings target
Inflation CalculatorPurchasing power of money over time
Simple Interest CalculatorInterest on principal only, without compounding

Loans & Credit

11 tools
Loan CalculatorMonthly payment and total interest on any loan
Amortization CalculatorFull schedule, extra payments and payoff date
Auto Loan CalculatorCar loan payments with trade-in and sales tax
Car Lease CalculatorMonthly lease payment from money factor and residual
Car Affordability CalculatorA car budget based on your income
Student Loan CalculatorPayoff time and interest on student loans
UK Student Loan Repayment CalculatorUK Plans 1, 2, 4, 5PAYE deduction above each plan threshold
Credit Card Payoff CalculatorTime to clear a card balance and interest paid
Credit Utilization CalculatorUtilization ratio across your cards
Debt Payoff CalculatorSnowball vs avalanche across multiple debts
Debt-to-Income Ratio CalculatorFront-end and back-end DTI for lending

Everyday & Business Finances

8 tools
Budget Calculator50/30/20 needs, wants and savings plan
Emergency Fund Calculator3 to 6 months of essential expenses
Savings CalculatorSavings growth with deposits and interest
Savings Goal CalculatorMonthly deposit needed to reach a target
Freelance Rate CalculatorHourly rate to cover costs, tax and time off
Commission CalculatorFlat and tiered sales commission
Discount CalculatorSale price, percentage off and savings
Currency ConverterConvert amounts between major currencies
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Formula-backed calculations checked against HMRC, IRS and other official guidance.

Precision-first financial modelling without intrusive tracking. Calculations run entirely in your browser.

Our MethodologyEmbed for Clients