Mortgage Payoff Calculator
The Mortgage Payoff Calculator tells you how many months and years it will take to pay off your current mortgage balance at your current payment, and how much interest you will pay in total. Enter an extra monthly payment to see how much sooner you can be mortgage-free and how much interest that saves.
What this means
Your payoff time is how many monthly payments are left at your current payment amount. Because interest is charged on the shrinking balance, extra principal payments have an outsized effect: money sent early skips all the future interest it would otherwise generate.
How we calculate it
Formula
Payoff months = log(PMT / (PMT − P × r)) / log(1 + r) — where P is the balance, r is the monthly rate and PMT is your monthly payment.Worked example
A $200,000 balance at 6.5% with a $2,000 monthly payment:
- 1Monthly rate = 6.5% / 12 = 0.5417%
- 2Payoff months ≈ 142 months (about 11.8 years)
- 3Total interest paid over that period ≈ $83,600
Important assumptions
- Your monthly payment stays fixed and is applied at the end of each month.
- The interest rate is fixed for the entire remaining term.
- Extra payments go directly to principal and there is no prepayment penalty.
Frequently asked questions
Should I make extra mortgage payments?
Usually yes if you have a stable emergency fund, no high-interest debt and no prepayment penalty. Every extra dollar toward principal avoids the interest that dollar would accrue for the rest of the loan.
Does paying biweekly save money?
Paying half your monthly payment every two weeks results in 26 half-payments — the equivalent of 13 full payments a year. That extra monthly payment accelerates payoff and reduces interest.
How much interest can I save by paying extra?
It depends on your rate and how early you start. On a typical 30-year mortgage, an extra $200 a month can cut several years off the term and save tens of thousands of dollars in interest.