Mortgage Calculator
Estimate your monthly mortgage payment, see a full amortization schedule, and find out how much extra payments could save you — free, instant, and private.
Updated June 2026 · Reviewed by the apitpi team · How we calculate
Taxes, insurance & extra payments
Estimated monthly payment
$2,573
$2,023 principal & interest
- Loan amount
- $320,000
- Total interest
- $408,142
- Total of payments
- $728,142
- Payoff date
- Jun 2056
Loan balance over time
How to use this mortgage calculator
Enter your home price, down payment, loan term, and interest rate to get an instant estimate of your monthly payment. Open Taxes, insurance & extra payments to add property tax, homeowners insurance, HOA dues, and optional extra principal. The breakdown chart shows exactly where each dollar of your payment goes.
What goes into a mortgage payment?
Lenders call it PITI — Principal, Interest, Taxes, and Insurance. Principal pays down your balance, interest is the cost of borrowing, and taxes and insurance are usually collected into an escrow account. If your down payment is below 20%, most lenders also add PMI until you build enough equity.
Example
On a $400,000 home with 20% down ($80,000) and a 30-year loan at 6.5%, the principal & interest payment is about $2,023/month. Adding $200/month in extra principal pays the loan off several years early and saves tens of thousands in interest — try it in the calculator above.
Mortgage calculator by state
Property taxes and home prices vary widely by state. Pick yours for a pre-filled estimate:
Frequently asked questions
How is my monthly mortgage payment calculated? +
Your principal and interest payment uses the standard amortization formula: M = P · r · (1+r)^n / ((1+r)^n − 1), where P is the loan amount, r is the monthly interest rate (annual rate ÷ 12), and n is the number of monthly payments. We then add monthly property tax, homeowners insurance, HOA dues, and PMI (if your down payment is under 20%) to show your full PITI payment.
What is PMI and when do I have to pay it? +
Private mortgage insurance (PMI) protects the lender if you default. It is typically required when your down payment is less than 20% of the home price, and usually costs about 0.3%–1.5% of the loan per year. This calculator estimates PMI at roughly 0.5% per year and drops it once your equity reaches 20%.
Should I choose a 15-year or 30-year mortgage? +
A 30-year loan has lower monthly payments but you pay far more total interest. A 15-year loan has higher monthly payments but a lower rate and dramatically less interest. Use the term buttons above to compare both instantly for your numbers.
How much do extra payments save me? +
Even small extra principal payments compound over time. Enter an amount in “Extra principal per month” to see exactly how much interest you save and how many years sooner you pay off the loan.
Is this mortgage calculator free? +
Yes. apitpi calculators are completely free, need no signup, and run entirely in your browser — your numbers are never sent anywhere.