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Calculate monthly mortgage payments, total interest, and view a full amortization breakdown. Compare 15 vs 30 year terms.
Calculate your monthly mortgage payment instantly — enter the home price, down payment, interest rate, and loan term. See your monthly payment broken down into principal and interest, total cost over the life of the loan, and how much you'll pay in interest. Compare different loan terms (15 vs 30 years) to find the right balance of monthly payment and total cost. Everything runs in your browser — no data stored.
Monthly payment = P[r(1+r)^n]/[(1+r)^n-1], where P is the loan amount, r is the monthly interest rate (annual rate / 12), and n is the total number of payments (years x 12). This formula gives you the fixed monthly payment of principal + interest.
A 15-year mortgage has higher monthly payments but saves tens of thousands in interest. A 30-year has lower payments but costs much more over time. For example, on a $300K loan at 7%: 30-year costs $418K in interest, 15-year costs $186K — a $232K difference.
This calculator shows principal and interest (P&I) only. Your actual monthly payment will also include property taxes, homeowner's insurance, and possibly PMI (private mortgage insurance if your down payment is under 20%).
A common guideline is that your total housing costs (mortgage + taxes + insurance) should not exceed 28% of your gross monthly income. Use this calculator to find a payment that fits within that range.