How mortgage payments work
Most fixed-rate loans use a level payment: your scheduled principal-and-interest payment stays the same, but the split changes. Early payments are mostly interest; later payments mostly pay down principal. This calculator uses the standard amortization formula so you can see that shift month by month.
What is amortization?
Amortization is the process of paying off debt over time with scheduled payments. Each payment covers interest accrued since the last payment, with the remainder reducing principal. The amortization schedule tabulates those amounts and the remaining balance after every payment.
How interest affects your loan
Interest accrues on the outstanding balance, not the original purchase price. That is why extra principal payments — even modest ones — can reduce total interest dramatically: they lower the balance earlier, so less interest compounds over the life of the loan.
Refinance checklist
When comparing a refinance, look beyond the monthly payment: consider closing costs, how long you plan to keep the loan, and whether you are resetting the amortization clock with a new term. This page highlights break-even timing and interest differences to support that decision.
Disclaimers
This tool provides estimates for education and planning. Actual lender pricing, escrow, mortgage insurance, HOA, and regulatory requirements are not modeled. Tax and investment guidance requires a qualified professional.