Amortization Calculator
See every single payment on a fixed-rate loan — how much of each goes to interest, how much retires principal, and what you still owe after it clears.
On this page
What an amortization schedule shows
An amortizing loan hides an odd fact behind a level payment: no two payments are alike. Each one covers the interest accrued since the last, and only the remainder reduces the debt — so as the balance falls, the interest charge falls, and the principal share of the very same payment grows. The schedule lays this out one row per payment, from the first (mostly interest) to the last (almost entirely principal).
This page builds the complete table for any fixed-rate loan — mortgage, auto, personal, student — with a year-by-year rollup, the full month-by-month detail, and a CSV download for spreadsheet work.
A worked example
Take $300,000 at 6.25% over 30 years. The payment is $1,847.15. In month one, $1,562.50 of it is interest — the balance times one twelfth of 6.25% — and only $284.65 touches the principal. Roughly 85 cents of every first-year dollar is interest.
The crossover, where a payment finally retires more principal than interest, does not arrive until well past the halfway point of the term. Over the full 360 payments, interest totals about $364,975 — more than the amount borrowed. None of that is unusual; it is simply what long terms at moderate rates cost, and the schedule is where you see it happen.
What the schedule is useful for
- Payoff planning. The balance column is the (approximate) payoff amount at any future date — what you would need to clear the loan when selling or refinancing.
- Sizing extra payments. Enter an extra amount and watch the schedule shorten. Early in the term, every extra dollar avoids decades of interest on itself; the same dollar near the end avoids almost none.
- Equity forecasting. On a mortgage, principal retired plus your down payment approximates the equity you have built from payments alone, before any price change.
- Interest deductions. The yearly interest column is what mortgage-interest reporting summarises, useful for a rough itemizing check ahead of Form 1098.
Reading the yearly rollup
The yearly table compresses the same information into one row per year. Watch the two columns swap dominance over the term: interest starts far larger and shrinks every year, principal starts small and grows. The year they cross is the psychological midpoint of the loan — typically much later than the calendar midpoint, which surprises most borrowers.
What this does not cover
- Escrow. Property tax, insurance, and PMI ride on top of a mortgage payment but are not part of amortization. The mortgage calculator includes them.
- Variable rates. The rate is held fixed; an ARM re-amortizes at each reset.
- Accrual conventions. Lenders that accrue daily will differ from this monthly model by small amounts per row.
- Fees and escrow shortages, which change the payment without touching the amortization.
See our methodology for how these tools are built and tested.
Frequently asked questions
Why does the final payment differ by a few cents?
Rounding. Each row rounds to whole cents, and over hundreds of payments the residue accumulates. The last payment absorbs it so the balance lands exactly on zero — which is what a real lender does too.
Is the balance column the same as my payoff amount?
Close, but not identical. A formal payoff quote adds interest accrued since your last payment through the payoff date, and any fees. The balance column is the right planning number; ask the lender for the binding one.
How do extra payments change the schedule?
Each extra dollar goes straight to principal, so every subsequent interest charge is computed on a smaller balance. The payment stays the same; the term shrinks. Enter an extra amount above and the schedule, the payoff date, and the interest total all update to show exactly what it buys.
Why is so much of a long loan's cost interest?
Because the balance stays high for so long. Interest accrues on what you owe, and a 30-year schedule keeps you owing most of the principal for more than a decade. Shorter terms cost less in total for exactly this reason — the balance falls faster, so there is less of it to charge interest on.
Does this work for biweekly payment plans?
This page models monthly payments. A true biweekly plan makes 26 half-payments a year — the equivalent of one extra monthly payment annually — and most of its benefit can be approximated here by entering one twelfth of a payment as a monthly extra.
Related calculators
This calculator is provided for general educational and estimation purposes only. It does not constitute financial or lending advice. Your lender's schedule is the authoritative one — daily accrual conventions, fees, and payment timing can shift individual rows by small amounts.