MortgageCalculatorTools

Mortgage Amortization Schedule

Build a payment-by-payment schedule showing the principal and interest split, the balance, and the payoff date.

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Free · No sign-up · Runs in your browser

An amortisation schedule is the clearest explanation of a mortgage available, because it shows what most borrowers find counter-intuitive: for the first several years, the great majority of each payment is interest.

This calculator builds the full schedule with dates, reports the split on the first and last payments, and shows what an extra monthly amount does to the payoff date.

Your numbers

Results update as you type. Nothing is sent anywhere.

Result

Monthly payment

$1,919

Total interest

$370,682

Total paid
$690,682
Payments to clear
360 months
Payoff date
2056-03-01
Interest in payment 1
$1,600.00
Principal in payment 1
$318.56
Interest in the final payment
$9.55

Early payments are mostly interest because interest is charged on the outstanding balance. The principal share grows every month.

Servicers may round the final payment slightly differently, so the last row can differ by a few cents from a lender statement.

Payment-by-payment schedule

PaymentAmountPrincipalInterestBalance
1. 2026-04$1,918.56$318.56$1,600.00$319,681
2. 2026-05$1,918.56$320.15$1,598.41$319,361
3. 2026-06$1,918.56$321.76$1,596.81$319,040
4. 2026-07$1,918.56$323.36$1,595.20$318,716
5. 2026-08$1,918.56$324.98$1,593.58$318,391
6. 2026-09$1,918.56$326.61$1,591.96$318,065
7. 2026-10$1,918.56$328.24$1,590.32$317,736
8. 2026-11$1,918.56$329.88$1,588.68$317,406
9. 2026-12$1,918.56$331.53$1,587.03$317,075
10. 2027-01$1,918.56$333.19$1,585.37$316,742
11. 2027-02$1,918.56$334.85$1,583.71$316,407
12. 2027-03$1,918.56$336.53$1,582.03$316,070

How to use the mortgage amortization schedule

  1. Enter the loan amount, rate and term.
  2. Enter the date of the first payment to get dated rows.
  3. Add an extra monthly payment if you want to see the accelerated schedule.
  4. Use the show-all control to expand the full payment list.

What people use this for

  • Seeing exactly how much of an early payment is interest.
  • Finding the balance at any point in the loan.
  • Testing the effect of extra payments on the payoff date.
  • Checking a lender statement against the expected schedule.

Worked examples

Every figure below is produced by running this calculator against the example inputs, so the numbers always match the tool.

A 30-year loan

$320,000 at 6% over 30 years with the first payment in April 2026.

Monthly payment
$1,919
Total interest
$370,682
Interest in payment 1
$1,600.00

The same loan with $250 extra each month

Identical terms with an additional $250 applied to principal.

Total interest
$262,067
Payments to clear
269 months
Payoff date
2048-08-01

Why early payments are mostly interest

Interest is charged on the outstanding balance, and at the start the balance is at its largest. On a $320,000 loan at 6%, the first month’s interest is $1,600 of a payment slightly under $1,920 - meaning barely $320 reduces the debt.

The proportion shifts every month as the balance falls, slowly at first and then rapidly. The crossover point, where principal first exceeds interest in a single payment, depends on the rate and term rather than the loan size.

What an extra payment does

An extra amount applied to principal removes not just that amount from the balance but every future month of interest that amount would have generated. That is why a modest extra payment early in a loan has a disproportionate effect.

Confirm with your servicer that extra funds are applied to principal rather than held as a prepaid future payment. The two produce very different outcomes, and the default is not always the one you want.

Methodology and assumptions

What this calculator does, and what it deliberately does not do.

  • Each row charges interest on the opening balance at the periodic rate, applies the remainder of the payment to principal, and carries the balance forward.
  • Extra payments are applied to principal after interest, which is how most servicers treat them.
  • The final payment is normally smaller than the others because only the remaining balance is due.
  • Results are estimates. Real quotes depend on credit, income, property, loan programme and lender pricing at the time of application.
  • Nothing you type is transmitted or stored - the calculation runs entirely inside your browser.

This calculator is provided for informational and educational purposes only. Results are estimates and may not reflect actual rates, fees, taxes, or market conditions.

This website is not a lender, a mortgage broker or a financial adviser. It does not originate loans, does not accept applications and does not forward your details to anyone.

Actual loan terms depend on credit history, income, the property, the loan programme and lender pricing at the time of application. Only a lender can tell you what you qualify for.

Frequently asked questions

Why does my lender’s schedule differ slightly?

Rounding conventions and day-count methods differ. Differences of a few cents per payment are normal; larger differences usually mean a different rate or term.

Can I see the balance at a specific date?

Yes - expand the full schedule and read the row for that payment. The remaining balance calculator gives the same figure directly.

Does this work for other loan types?

Any level-payment amortising loan: auto, personal, business. The arithmetic is identical.

What happens on an adjustable-rate mortgage?

This schedule assumes a fixed rate throughout. An adjustable loan needs recalculating at each reset with the new rate and remaining term.

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