Free Mortgage Calculator — Monthly Payment, PITI & Amortization

How to use the mortgage calculator

Enter the home price and down payment. The loan amount is the difference.
Add rate and term. 30-year fixed is the default; try 15 to see the interest collapse.
Include tax, insurance, HOA. That turns P&I into PITI — your true monthly housing cost.
Press Calculate. Expand any year to see all twelve monthly splits.

How is the monthly mortgage payment calculated?

With the amortization formula: M = P × r(1+r)^n / ((1+r)^n − 1), where P is the loan amount, r the monthly rate, and n the number of payments.

What is PITI?

Principal, Interest, Taxes, and Insurance — the four parts of most mortgage bills. Lenders use PITI (plus HOA) to judge affordability.

Why is my first payment almost all interest?

Interest is charged on the full balance each month. As the balance shrinks, the interest slice shrinks and the principal slice grows.

Does a bigger down payment matter beyond the loan size?

Yes — 20% down usually avoids private mortgage insurance (PMI), and a smaller loan means less total interest.

15-year vs 30-year: which saves more?

A 15-year term has higher payments but a lower rate and far less total interest — often hundreds of thousands less on a typical home.

Is this financial advice?

No. These are planning estimates, not financial advice. Confirm real terms with your lender.

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Monthly payment, PITI, and full amortization schedule.

This tool is free, with no account and no ads. If it saved you some time, consider supporting the indie dev behind it.