Mortgage Payment Calculator
Enter the home price, your down payment, rate, and term. You'll get the monthly principal-and-interest payment, total interest over the life of the loan, and a year-by-year amortization schedule.
The purchase price, before closing costs
20% avoids PMI; many buyers put down less
The annual rate on your mortgage quote
30 years is standard; 15 builds equity faster
Property tax and homeowners insurance, if you know them
Monthly payment (P&I)
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Enter a price and down payment
Total interest over the loan
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Total cost
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Amortization front-loads the interest
A fixed mortgage payment never changes, but what's inside it does. Each month the lender takes interest on the remaining balance first, and only the leftover chips away at principal. On a $320,000 loan at 6.5%, the first payment is about $1,733 of interest and just $290 of principal. That's amortization: the balance barely moves in the early years, then falls faster and faster as the interest share shrinks. Open the year-by-year table above and you can watch the crossover happen.
What rate and term really change
The rate sets the price of every borrowed dollar, and the term sets how long you pay it. A single percentage point on a $320,000 loan moves the payment by roughly $210 a month and the lifetime interest by about $75,000. The term is the bigger lever: switch the slider from 30 years to 15 and the payment rises by around 45%, while total interest drops by more than half. Whether the payment fits is a question for the home affordability calculator and your debt-to-income ratio, and if you land in a 30-year, extra principal payments (test them in the loan payoff calculator) quietly rebuild the 15-year math on your own schedule.
The down payment decides more than the loan size
A bigger down payment shrinks the loan, the payment, and the lifetime interest all at once, and at 20% it removes PMI from the equation entirely. Below that line, lenders add insurance that protects them with your money, often $130-400 a month on a typical loan. Getting to 20% is a multi-year savings project for most buyers (our down payment guide maps it out), and it's exactly the kind of long goal that works better tracked than remembered, the job Stoia was built around.
Frequently asked questions
How is a monthly mortgage payment calculated?
From three numbers: the loan amount (price minus down payment), the monthly interest rate, and the number of payments. The standard amortization formula sets one fixed payment that covers that month's interest plus enough principal to reach exactly zero on the last payment. Early on, most of the payment is interest; by the end, almost all of it is principal.
What's the difference between a 15-year and a 30-year mortgage?
The 30-year has a lower monthly payment but you pay interest for twice as long, so the total interest is usually 2 to 2.5 times higher. A 15-year costs more per month (typically 40-50% more, not double) and usually carries a slightly lower rate. Try both terms in the calculator: the total-interest gap is the number that changes minds.
What is PMI and when do I pay it?
Private mortgage insurance: a fee lenders charge when your down payment is under 20% of the price, usually 0.5-1.5% of the loan per year, added to your monthly payment. It protects the lender, not you. You can request removal once you reach 20% equity, and it must end automatically at 22%.
Does this calculator include property taxes and insurance?
The main payment shown is principal and interest only. If you enter a monthly taxes-and-insurance estimate, the calculator adds it so you see the full monthly outlay. Most lenders collect these through an escrow account on top of the loan payment, commonly $300-700 a month depending on the home and state.
How much interest will I really pay over 30 years?
At rates around 6-7%, total interest on a 30-year loan often lands close to or above the amount you borrowed. On a $320,000 loan at 6.5%, interest comes to roughly $408,000 over 30 years. The year-by-year table shows how slowly the balance falls in the first decade.
Does this calculator save my numbers?
No. Everything runs in your browser and disappears when you leave. Nothing is uploaded or stored.
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