Mortgage Calculator

Calculate your monthly mortgage payments, total interest, and total cost.

Loan Details
Adjust the parameters of your loan.
$300,000
5.5%
30 years
Payment Summary
Your estimated payment details.
$1,703.37
Principal Amount$300,000
Total Interest$313,212.12
Total Cost of Loan$613,212.12

About the Mortgage Calculator

This mortgage calculator uses the standard fixed-rate amortization formula — the same one banks use to determine your monthly payment — to break down principal and interest for any loan amount, interest rate, and term. The full amortization schedule shows exactly how much of each monthly payment goes to interest versus principal, so you can see the real cost of a 30-year vs. 15-year loan or model the impact of an extra principal payment. Calculations run in your browser; nothing is logged, and you'll never be asked for your name, email, or zip code.

Common use cases

Why client-side?

Every byte you paste, type, or upload here is processed entirely inside your browser. Nothing is sent to a server, logged, or stored. That means it's safe to use this tool on production secrets, customer data, internal logs, and any input you would not paste into a hosted SaaS formatter.

Frequently Asked Questions

How do I calculate my monthly mortgage payment?
Enter your loan amount, annual interest rate, and loan term in years. The calculator instantly shows your monthly payment, total interest, and total cost.
What is included in a mortgage payment?
A basic mortgage payment includes principal and interest. This calculator focuses on these components. Property taxes, homeowner's insurance, and PMI are additional costs to consider.
How accurate is this mortgage calculator?
The calculator uses the standard amortization formula used by banks and lenders. Results are accurate for fixed-rate mortgage estimates.