Calculate Monthly Mortgage Payments in Excel Spreadsheet programs, such as Microsoft Excel and Google Sheets, include a payment function that can calculate the principal and interest on a mortgage.

If you got that same loan today—at the current 7.03% rate —your monthly payment would drop by more than $200 to $2,666. You’d also save around $75,000 on interest over the life of your loan.

How To Calculate Monthly Loan Interest Since most loans require a monthly payment, it’s helpful to be able to determine the interest rate using months as well.