Mortgage Payoff Calculator

A mortgage payoff calculator estimates how extra monthly payments change your remaining payoff time, total interest, and full repayment cost. Enter your current mortgage balance, rate, remaining term, and added payment to see how much faster you can own the home free and clear.

A mortgage payoff calculator estimates how long it will take to fully repay a home loan based on the remaining balance, interest rate, scheduled term, and any extra payment you plan to send each month. Instead of looking only at the standard mortgage payment, the calculator focuses on the payoff path from today forward. That makes it useful for homeowners who already have a mortgage and want to know how faster repayment changes interest cost.

In a typical amortizing mortgage, interest is charged on the remaining principal balance every month. Because the balance is larger early in the loan, a bigger share of each payment goes to interest at the start and a smaller share reduces principal. A mortgage payoff calculator shows what happens when you add extra principal. The added amount reduces the balance sooner, which lowers future interest charges and shortens the number of payments left.

Homeowners use a mortgage payoff calculator when deciding whether to make an extra $100, $250, or $500 payment each month, when comparing payoff versus investing spare cash elsewhere, and when planning for retirement or debt reduction goals. It is also practical after refinancing, receiving a raise, or paying off another loan. Seeing the months saved and interest avoided helps turn an abstract goal like “pay off the mortgage early” into a concrete, testable plan.

1. Enter your current mortgage balance, not the original loan amount from closing.
2. Add your mortgage interest rate as an annual percentage rate.
3. Enter the number of years remaining on the mortgage so the calculator can estimate the scheduled payment.
4. Input the extra monthly amount you want to pay toward principal.
5. Click Calculate to see the revised payoff time, months saved, interest saved, and total interest remaining.
6. Test several extra payment amounts to find a strategy that fits your monthly cash flow.

n = -ln(1 - rP / M) / ln(1 + r)

• n: number of months to pay off the mortgage.
• P: current principal balance.
• r: monthly interest rate, equal to APR divided by 12.
• M: total monthly payment, including any extra principal.
• Rule: payment must be higher than monthly interest for payoff to occur.

Scheduled Monthly Payment

This is the standard principal-and-interest payment implied by the current balance, rate, and remaining term before any extra amount is added.

Payment With Extra

This is the actual monthly outflow used in the payoff scenario. It combines the scheduled payment with your extra principal contribution.

New Payoff Time

This shows how long the mortgage would last under the updated payment plan. Shorter payoff time means fewer months of interest charges.

Time Saved

This compares the revised payoff schedule with the original remaining term and translates the benefit into months or years saved.

Interest Saved

This estimates how much interest you avoid by reducing principal earlier instead of following the original amortization schedule.

Assume a remaining mortgage balance of $315,000, an interest rate of 6.25%, and 27 years left on the loan. You decide to add an extra $300 per month toward principal.

First, estimate the scheduled principal-and-interest payment on the remaining balance and term. In this case, the normal payment is about $2,039 per month. Adding $300 raises the total monthly payment to about $2,339. From there, the calculator applies each month's interest charge to the declining balance and tracks how quickly principal falls.

Final result: the mortgage pays off in about 21 years 3 months instead of 27 years, saving roughly 5 years 9 months. Total interest from today forward drops by about $71,000. The outcome shows why consistent extra principal can be powerful: a relatively modest monthly increase can remove years from the loan and reduce long-run borrowing cost substantially.