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Mortgage Calculators

Mortgage Amortization Calculator

Generate a full month-by-month amortization schedule for any mortgage, with the principal/interest split and running balance for every payment.

Uses the standard fixed-rate amortization formula your lender uses to compute each scheduled payment.

$
%
yr
$
Monthly payment (P&I)
$2,212
Payoff in 30 yr · Total interest $446,406
Total of payments
$796,406
Total interest
$446,406
Total principal
$350,000
Number of payments
360
Yearly summary
YearPrincipalInterestEnd balance
1$3,912$22,635$346,088
2$4,174$22,373$341,914
3$4,454$22,093$337,460
4$4,752$21,795$332,709
5$5,070$21,477$327,638
6$5,410$21,137$322,229
7$5,772$20,775$316,457
8$6,158$20,388$310,298
9$6,571$19,976$303,727
10$7,011$19,536$296,716
11$7,481$19,066$289,236
12$7,982$18,565$281,254
13$8,516$18,031$272,738
14$9,086$17,460$263,652
15$9,695$16,852$253,957
16$10,344$16,203$243,613
17$11,037$15,510$232,576
18$11,776$14,771$220,800
19$12,565$13,982$208,235
20$13,406$13,141$194,828
21$14,304$12,243$180,524
22$15,262$11,285$165,262
23$16,284$10,263$148,978
24$17,375$9,172$131,603
25$18,538$8,008$113,065
26$19,780$6,767$93,285
27$21,105$5,442$72,180
28$22,518$4,029$49,662
29$24,026$2,521$25,635
30$25,635$912$0
Overview

How the Mortgage Amortization Calculator Works

An amortization schedule shows where every dollar of every mortgage payment actually goes. Early payments are almost all interest; later payments are almost all principal. This calculator runs the full schedule for any loan and summarizes it year by year so the structure is obvious at a glance.

Formula

The Math Behind the Calculator

Monthly payment M = P × r / (1 − (1 + r)^−n), where P is loan principal, r is monthly rate, n is total payments. For each month: interest = balance × r; principal = M − interest; balance −= principal. Repeat for n months.

Example

A Worked Example

On a $350,000, 30-year loan at 6.5%: monthly payment ≈ $2,212. Month 1 splits ≈ $1,896 interest / $316 principal. Month 240 (year 20) splits ≈ $937 / $1,275. Total interest over 30 years ≈ $446,300.

How to use

How to Use the Mortgage Amortization Calculator

  1. 1Enter the loan amount, interest rate, and term in years.
  2. 2Optionally add an extra monthly principal payment to see how it shortens the schedule.
  3. 3Review the yearly summary — interest dominates for the first half of a 30-year loan.
  4. 4Expand the full table to see every month if you want to verify a payment or plan a recast.
Interpretation

What the Results Mean

  • Monthly payment is fixed for a standard fixed-rate loan.
  • The principal/interest split changes every month — even though the payment doesn't.
  • Total interest paid is often as much as or more than the original loan amount on a 30-year mortgage.
Avoid

Common Mistakes to Avoid

  • Assuming the principal/interest split is constant — it shifts every single month.
  • Sending extra principal but forgetting to mark it 'principal only' with the servicer.
  • Treating the published payment as the total monthly cost — it doesn't include taxes, insurance, HOA, or PMI.
Keep going

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FAQ

Frequently Asked Questions

Why is so much of my early payment going to interest?+

Because interest is computed on the current balance, which is largest at the start. As the balance falls, the interest portion falls too and principal grows.

Does an extra payment really save that much?+

Yes — extra principal eliminates all the future interest that balance would have generated, which compounds the longer the loan has left.

Will my schedule match the lender's exactly?+

It will match very closely. Tiny rounding differences are normal because lenders round each month to the cent in slightly different ways.

Financial Disclaimer

This calculator is for educational and estimation purposes only. It does not provide financial, mortgage, tax, investment, or legal advice. Actual rates, payments, taxes, fees, insurance costs, eligibility, and loan terms vary by lender, location, credit profile, and market conditions. Always compare official offers and consult a qualified professional before making financial decisions.

Last updated June 2026 · Prepared by the mCalculator Editorial Team