Mortgage Payoff Estimator & Early Payoff Calculator

Estimate how much faster you can pay off your mortgage and how much interest you'll save by making extra monthly or one-time principal payments.

Mathematical Audit

Mortgage Payoff Formula

The calculator first determines your scheduled monthly principal & interest payment using the standard amortization formula, then simulates two payoff schedules month by month: one with scheduled payments only, and one that adds your extra monthly and/or one-time payments directly to principal.

Monthly Payment (M) = P × [r(1 + r)^n] ÷ [(1 + r)^n − 1]
Monthly Interest = Remaining Balance × (Annual Rate ÷ 12)
Monthly Principal Paid = (M + Extra Payment) − Monthly Interest
New Balance = Previous Balance − Monthly Principal Paid
Interest Saved = Original Total Interest − Accelerated Total Interest

P is your current loan balance, r is the monthly interest rate (annual rate ÷ 12), and n is the number of months remaining on your loan. A one-time extra payment is applied immediately to reduce the starting balance before the schedule is simulated.

Operational Guide

How to Use the Mortgage Payoff Calculator

1

Enter your current loan details

Input your current remaining mortgage balance, your annual interest rate, and the number of years left on your loan term (check your latest mortgage statement for these figures).

2

Add any extra payments

Enter an extra amount you plan to pay toward principal every month, and/or a one-time lump-sum payment you intend to make now (such as a bonus or tax refund).

3

Select your display currency

Choose USD, EUR, GBP, JPY, AUD, or CAD to view all results converted into your preferred currency.

4

Click Calculate

Instantly compare your original payoff timeline against your accelerated timeline, including total interest saved and the number of months shaved off your loan.

5

Save or share your results

Use the Share button to generate a link that restores these exact inputs, or save the calculation to revisit it later from your saved calculations library.

Real-World Scenario Example

"A homeowner has a $300,000 remaining balance at a 6.5% interest rate with 25 years left on the loan, and decides to pay an extra $200 toward principal every month."

Inputs

currentBalance:300000
interestRate:6.5
remainingTermYears:25
extraMonthlyPayment:200
oneTimeExtraPayment:0

Result

Scheduled payment: $2,025.62/month. Without extra payments, the loan takes 25 years and costs $307,686 in interest. With the extra $200/month, it's paid off in 20 years 3 months (243 months) — saving 4 years 9 months and $68,042 in interest.

Important Disclaimer

This calculator provides estimates for educational purposes only and does not constitute financial advice. Actual payoff amounts include per-diem interest, fees, and servicer-specific calculations that may differ from this estimate. Contact your loan servicer for an official payoff quote.