Amortization Calculator
See your monthly payment broken down into principal and interest, plus total interest over the life of the loan.
How amortization works
Every fixed-rate loan payment is split between interest and principal, but that split isn't constant — early payments are weighted heavily toward interest, since interest is calculated on the full remaining balance. As the balance shrinks over time, more of each payment shifts toward paying down principal.
This is why paying extra toward principal early in a loan has an outsized effect on total interest paid — reducing the balance sooner means less interest accrues on it for the rest of the loan's life.
Why your first payment is mostly interest
On a 30-year mortgage, it's common for well over half of the first several years of payments to go toward interest rather than principal. This can feel discouraging, but it's simply a mathematical consequence of interest being calculated on a large remaining balance early on.
The crossover point — where more of your payment goes to principal than interest — happens roughly halfway through the loan term for a typical fixed-rate loan, though extra principal payments can shift that point significantly earlier.
Frequently asked questions
Why does most of my early payment go to interest?
Interest is calculated on the remaining loan balance, which is largest at the start of the loan — as the balance shrinks with each payment, less interest accrues and more of the payment goes toward principal.
Does paying extra toward principal reduce total interest?
Yes, significantly — reducing the balance early means less interest accrues on it for the remainder of the loan, which can save a substantial amount over the full term.
Is this the same as a full amortization schedule?
This calculator shows the monthly payment and the first payment's principal/interest split along with lifetime totals, rather than a full month-by-month schedule.