Mortgage Calculator
Estimate your monthly mortgage payment, and see the total interest you’ll pay over the life of the loan.
Understanding the Mortgage Calculator
A mortgage payment is calculated so that a fixed monthly amount fully pays off the loan by the end of its term, with each payment split between interest (larger at first) and principal (larger toward the end). This calculator uses the standard amortization formula to find that fixed monthly principal-and-interest payment.
Your down payment directly reduces the loan amount you’re borrowing and financing interest on — a larger down payment means a smaller loan, a smaller monthly payment, and typically less interest paid in total over the loan’s life.
This figure covers principal and interest only. Real monthly housing costs usually also include property taxes, homeowners insurance, and possibly HOA dues or private mortgage insurance — budget for those separately on top of the number shown here.
See it in practice
Example 1 — 30-year fixed mortgage
Example 2 — Same loan, 15-year term
Common questions
No — this is principal and interest only. Lenders often quote a combined ‘PITI’ figure that adds estimated property taxes, homeowners insurance, and mortgage insurance if applicable; check with your lender for those local estimates.
20% avoids private mortgage insurance (PMI) on a conventional loan, but many buyers put down less. A smaller down payment means a larger loan and typically an added PMI cost until enough equity builds up.
A shorter term means less time for interest to accrue, and it also usually comes with a lower rate. The trade-off is a meaningfully higher monthly payment, since the same loan is being repaid faster.
This tool assumes a fixed rate for the full term. If you’re considering an adjustable-rate mortgage, run the calculator at both your introductory rate and a higher potential future rate to see the range of possible payments.
A common guideline is keeping your total monthly housing payment, including taxes and insurance, at or below 28% of your gross monthly income. Lenders also look at your total debt-to-income ratio, typically capping it around 36-43%, when deciding how large a mortgage to approve.
Putting down 20% avoids private mortgage insurance (PMI) and lowers your monthly payment, but it isn’t required. Many loan programs accept less, sometimes as low as 3-5%, though a smaller down payment usually means PMI and a larger loan amount.
No, extra principal payments don’t lower your required monthly payment; they reduce the loan balance and shorten how long you’ll be paying, cutting total interest. Your regular monthly payment stays the same unless you formally recast or refinance the loan.
Lenders typically reserve their best rates for borrowers with credit scores above 740-760, though conventional loans are often available with scores as low as the high 600s. A higher score generally means a lower rate and lower total interest over the life of the loan.