Mortgage Calculator
Estimate your monthly mortgage payments and total interest over the life of your loan. Enter your home price, down payment, interest rate, and loan term.
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Your Mortgage Breakdown
Monthly Payment
$1,516.96
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How It Works
The mortgage calculator uses the standard amortization formula to determine your monthly payment. The formula takes your loan principal (home price minus down payment), divides the annual interest rate by 12 to get the monthly rate, and calculates the fixed payment needed to fully repay the loan over your chosen term.
The formula is: M = P × [r(1+r)^n] / [(1+r)^n – 1], where M is the monthly payment, P is the principal, r is the monthly interest rate, and n is the total number of payments.
This calculation assumes a fixed-rate mortgage with consistent monthly payments throughout the loan term. Actual payments may vary based on property taxes, homeowner's insurance, PMI, and HOA fees which are not included in this basic calculation.
Worked example: on a $300,000 loan over 30 years at 6% interest, the monthly rate is 0.5% across 360 payments, giving a payment of about $1,799 per month. Over the full term you would pay roughly $647,500 in total — about $347,500 of it interest, more than the original loan itself. This is why even a small rate reduction matters: the same loan at 5.5% costs about $1,703 per month, saving over $34,000 across the term.
Frequently Asked Questions
Written by the Tools & Deals Hub Editorial Team · Reviewed by Durga Prasad Mogulothu, Founder · Last reviewed:
Sources & further reading
- CFPB — Consumer tools (loans, mortgages, savings)
- Investor.gov — Free financial calculators (U.S. SEC)
Results are estimates for planning, not professional advice. Figures can change after publication — check the source for current numbers.