Mortgage Calculator

Mortgage Amount ($) Enter a valid loan amount.

Annual Interest Rate (%) Enter a valid interest rate.

Loan Term (years) Enter a valid loan term.

Monthly Payment

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Total Interest Paid

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Total Amount Paid

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How to Use This Tool

Enter the total mortgage amount you plan to borrow.
Enter the annual interest rate offered by your lender.
Enter the loan term in years.
Click Calculate Payment to see your monthly payment, total interest, and total amount paid over the life of the loan.

The Loan Payment Formula

Monthly loan payments are calculated using the standard amortization formula:

M = P × [r(1+r)ⁿ] ÷ [(1+r)ⁿ − 1]

Where M is the monthly payment, P is the loan principal, r is the monthly interest rate (annual rate ÷ 12), and n is the total number of monthly payments (years × 12).

Why This Formula Works

This formula ensures that each fixed monthly payment covers that month's interest charge plus a portion of the principal, structured so the loan balance reaches exactly zero at the end of the term — a process called amortization. In the early years of a loan, a larger share of each payment goes toward interest; over time, more goes toward principal.

What This Doesn't Include

This calculator shows principal and interest only. Your actual monthly mortgage payment (often called "PITI") typically also includes property taxes, homeowners insurance, and if applicable, private mortgage insurance (PMI) or HOA fees — all of which vary by location and lender.

Factors That Affect Your Payment

Interest rate: Even a small rate difference compounds significantly over a long loan term
Loan term: A longer term lowers your monthly payment but increases total interest paid over the life of the loan
Loan amount: Directly proportional to your payment — a larger loan means a larger payment at the same rate and term

Frequently Asked Questions

What is the formula used to calculate my monthly payment?

M = P × [r(1+r)ⁿ] ÷ [(1+r)ⁿ − 1], where P is the loan amount, r is the monthly interest rate, and n is the total number of monthly payments.

Does a longer loan term always cost more overall?

Yes — while a longer term reduces your monthly payment, you pay interest for more months, which increases the total interest paid over the life of the loan, even at the same interest rate.

What is PITI?

PITI stands for Principal, Interest, Taxes, and Insurance — the four components that typically make up a full monthly mortgage payment. This calculator estimates only the Principal and Interest (P&I) portion.

What is a typical mortgage term?

The most common mortgage terms in the US are 30 years and 15 years. A 15-year term has higher monthly payments but substantially less total interest paid over the life of the loan.

This calculator is provided for general informational and estimation purposes only. Results should not be treated as professional financial, tax, legal, medical, or engineering advice. Always verify critical calculations with a qualified professional or official source before making decisions.