Mortgage Calculator
Calculate your monthly mortgage payment, total cost, and interest breakdown.
Overview
A mortgage payment is calculated with the same annuity formula as any amortising loan, but the term is long enough that small rate differences produce large absolute effects. Over thirty years, a one-percentage-point rate increase raises the monthly payment by roughly ten percent and total interest by considerably more, because the increase applies to a balance that amortises slowly.
Monthly Payment
$
Loan Amount
$
Total Payment
$
Total Interest
$
Formula
M = monthly payment
P = loan principal (home price minus down payment)
r = monthly interest rate (annual rate / 12)
n = total number of payments (years x 12)
How to Use
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1
Enter the loan amount and rate
Type the mortgage principal, annual interest rate, and term in years.
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2
Review the monthly payment
The monthly principal-and-interest payment is calculated instantly.
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3
See total interest and schedule
The full amortization schedule and total interest paid over the loan are displayed.
About
Term length trades monthly affordability against lifetime cost. A fifteen-year mortgage carries a substantially higher payment than a thirty-year one at the same rate yet costs less than half the total interest, since the balance falls far faster and less of it is exposed to interest for less time.
The calculated payment covers principal and interest only. Property tax, insurance and, where applicable, mortgage insurance and association fees are collected alongside it, so the amount actually debited commonly exceeds the amortisation figure by a fifth or more.