Mortgage Comparison Calculator

About this calculator

A mortgage comparison lays two loan offers side by side — each with its own loan amount, interest rate, and term — and computes the monthly principal-and-interest payment for both using the standard amortization formula, then totals the interest paid over the full life of each loan. This turns two headline rates into concrete dollar figures that are actually comparable.

Homebuyers use this comparison when shopping quotes from multiple lenders, or when weighing a lower rate with a shorter term against a higher rate with a longer term, since a lower monthly payment does not always mean a lower total cost — a 30-year loan at a slightly lower rate can still cost tens of thousands more in interest than a 20-year loan at a slightly higher one. Mortgage brokers and loan officers run the same side-by-side math to explain trade-offs like paying points to buy down a rate.

This calculator takes the loan amount, interest rate, and term for two offers and returns each one's monthly payment and total interest cost, so you can see at a glance which offer actually saves you more money.