CompoundInterestCalc
Free online tool · Real estate

Mortgage Payoff Calculator

Use this free mortgage payoff calculator to see how fast you could be mortgage-free. Add an extra monthly payment, drop in a one-time lump sum, or switch to biweekly payments — and watch the payoff date jump forward.

The tool shows exactly how much interest you'd save and how many years you'd cut off the loan, side by side with your current schedule. Small, steady over-payments have a surprisingly large effect. No account, no sign-up, no spreadsheet.

Your mortgage
$
%
30 years
Speed it up
$
$
Interest saved
$0
Time saved
—
New payoff time
—
Payment /mo
$0
Total interest paid
Balance over time
As scheduled Paying it down

Estimates are for illustration and education only — not a loan offer. Confirm your lender allows extra principal payments with no prepayment penalty.

The math

Why extra payments work so well

Every dollar you pay above the scheduled amount goes straight to principal. That permanently removes all the future interest that dollar would otherwise have generated — so the earlier and more often you over-pay, the more you save.

Each month : Interest = Balance · rate⁄12 , Principal = Payment + Extra − Interest
A lower balance next month means a smaller interest charge, so even more of the following payment attacks principal — the effect compounds.
Biweekly : 26 half-payments a year = 13 monthly payments
Paying half every two weeks slips in one extra full payment each year without you noticing.
Worked example. On a $300,000 balance at 6.5% over 30 years the payment is about $1,896 and you'd pay roughly $382,000 in interest. Add just $200 a month and you'd be mortgage-free about 6 years early and save around $90,000 in interest — for $200 you were already spending elsewhere.
See it in action

Three ways to pay off early

Different strategies on a typical loan. Load any one into the calculator and adjust from there.

Quick guide

How to use the mortgage payoff calculator

Four short steps. Change any field and the savings, payoff time and chart update instantly.

Step 1

Enter your balance

The amount still owed today, not the original loan. This is what the payoff is measured against.

Step 2

Rate and years left

Your fixed rate and how many years remain, so the tool knows your current payment and baseline payoff.

Step 3

Choose how to speed it up

Add an extra monthly amount, a one-time lump sum, tick biweekly payments — or combine all three.

Step 4

Read the savings

See the interest saved, the years cut off, and the two balance curves converging to zero on the chart.

Good to understand

Paying off your mortgage early

Paying your mortgage off ahead of schedule is one of the simplest, lowest-risk returns available: every extra dollar of principal saves you the interest rate on your loan, guaranteed. On a 6.5% mortgage that's effectively a 6.5% risk-free return — hard to beat almost anywhere else.

Extra monthly payments

The steadiest approach. Rounding your payment up, or adding a fixed extra amount each month, chips away at principal relentlessly. Because the effect compounds, even a modest extra payment can cut years off a 30-year loan and save tens of thousands.

A one-time lump sum

Windfalls — a bonus, tax refund or inheritance — applied directly to principal have an outsized effect early in the loan, when the balance and interest charges are highest. The tool lets you test any lump sum against the schedule.

Biweekly payments

Paying half your monthly amount every two weeks results in 26 half-payments — the equivalent of 13 monthly payments a year instead of 12. That one extra payment, made almost painlessly, typically shaves several years off a long mortgage.

Before you over-pay

Confirm your lender applies extra money to principal and charges no prepayment penalty. And weigh it against other goals: high-interest debt, an emergency fund, and employer-matched retirement contributions usually come first. If your mortgage rate is low, investing the difference may beat paying it down — compare with the compound interest calculator.

Who it's for

Any homeowner wondering whether over-paying is worth it, and how much of a difference their spare cash would make. You only need your balance, rate and years remaining to start.

Want the full month-by-month schedule instead? See the amortization calculator, or browse all our free tools.

Quick answers

Mortgage payoff calculator FAQ

Is this mortgage payoff calculator free?
Yes — it's completely free, runs entirely in your browser, and requires no account or sign-up. Your numbers are never sent to us or stored on a server.
How much do extra payments really save?
More than most people expect. Because extra money goes entirely to principal and removes all its future interest, even $100–$200 a month can save tens of thousands and cut years off a 30-year loan. Enter your own numbers to see the exact figure.
Do biweekly payments actually help?
Yes. Paying half your monthly amount every two weeks means 26 half-payments a year — the equivalent of one extra full payment. That single extra payment typically shortens a 30-year mortgage by four to six years.
Should I pay off my mortgage or invest?
It depends on your mortgage rate versus expected investment returns, and your appetite for risk. Paying down the loan is a guaranteed return equal to your rate; investing may earn more but isn't guaranteed. Clear high-interest debt and build an emergency fund first.
Is this financial advice?
No. This is an educational tool showing illustrative estimates. Real results depend on your lender's terms, any prepayment penalties, and how consistently you over-pay. Confirm the details with your lender before deciding.