Mortgage Calculator
Estimate your monthly mortgage payment - including taxes, insurance, and PMI - and see exactly how much interest you'll pay over the life of the loan.
Mortgage Calculator
20.0% of the price · $80,000
Not charged - your down payment is 20% or more
Applied entirely to principal, every month
Monthly payment
$2,514
- Principal & interest$2,02380%
- Property tax$36715%
- Insurance$1255%
Total interest
$408,142
Total cost
$808,142
Including down payment
Payoff in
30 years
Paid off
September 2056
Where the money goes
- Principal (the home)$320,000
- Interest (the lender)$408,142
Principal vs interest, year by year
Early payments are mostly interest. The bars invert as the balance falls.
How the mortgage calculation works
A mortgage calculator turns four numbers — your loan amount, interest rate, loan term, and down payment — into the one number that actually matters: your monthly payment. But the real payment you send your lender each month is usually bigger than just principal and interest, so it helps to understand what goes into it.
Lenders call the full payment PITI: Principal, Interest, Taxes, and Insurance. Principal is the slice that pays down what you borrowed. Interest is the lender's charge for the loan. Taxes are your property taxes, and insurance is your homeowners policy — both are often collected monthly and held in an escrow account. If your down payment is under 20%, you'll usually also pay PMI (private mortgage insurance) until you've built enough equity.
The principal-and-interest part is calculated with the standard amortizing-loan formula:
M = P × [ r(1 + r)ⁿ ] / [ (1 + r)ⁿ − 1 ]
where P is the loan amount, r is the monthly interest rate (your annual rate ÷ 12), and n is the number of monthly payments (years × 12).
Here's a worked example. On a $400,000 home with 20% down ($80,000), you'd borrow $320,000. At a 6.5% rate over 30 years, your principal and interest come to about $2,023 a month. Add roughly $367 for property tax and $125 for insurance and your true monthly payment is closer to $2,515.
The number most buyers overlook is the total interest. On that same loan you'd pay about $408,000 in interest over 30 years — more than the house itself. That is why small changes matter so much:
- Extra payments compound. Adding just $200 a month to that loan pays it off about six years early and saves roughly $90,000 in interest, because every extra dollar goes straight to principal and stops accruing interest immediately.
- Term versus rate. A 15-year mortgage carries a higher monthly payment but a lower rate and dramatically less total interest than a 30-year. Run both before assuming the longer term is more affordable.
- Reaching 20% equity ends PMI. On most conventional loans you can request cancellation once your balance falls to 80% of the original value, which removes a cost that buys you nothing.
Use the calculator above to test different prices, rates, and down payments — then try the extra-payment field and watch the total interest fall.
Disclaimer: This calculator provides estimates for informational purposes only and is not financial advice. Your actual rate, taxes, fees, and payment will vary - confirm figures with a licensed lender or financial professional.
Frequently asked questions
How is my monthly mortgage payment calculated?
Principal and interest use the standard amortization formula based on your loan amount, monthly interest rate (annual rate divided by 12), and number of payments (years times 12). Property taxes, homeowners insurance, HOA dues, and PMI are then added on top to give your full monthly payment.
What does PITI include?
PITI stands for Principal, Interest, Taxes, and Insurance - the four parts of a typical monthly mortgage payment. Many lenders collect the tax and insurance portions in an escrow account and pay those bills on your behalf when they come due.
How much should my down payment be?
A 20% down payment lets you avoid PMI and lowers your loan amount, but many loan programs allow far less - 3% to 5% is common for conventional loans, and VA and USDA loans can require nothing down. A larger down payment means a smaller loan, a lower monthly payment, and less total interest.
What is PMI and when does it go away?
Private mortgage insurance is an extra monthly cost lenders charge when your down payment is under 20%. It protects the lender, not you. On most conventional loans you can request cancellation once you reach about 20% equity, and it must be removed automatically at 22% equity based on the original schedule.
Should I choose a 15-year or 30-year mortgage?
A 30-year loan has lower monthly payments; a 15-year loan has higher payments but a lower interest rate and far less total interest. Choose based on the monthly payment you can comfortably afford alongside your other goals, rather than assuming the shortest term is always best.
How much can extra payments save me?
Extra payments go entirely toward principal, so they shorten the loan and cut interest sharply. On a typical $320,000 30-year loan at 6.5%, an extra $200 a month saves around $90,000 in interest and shaves roughly six years off the term. Use the extra-payment field above to test your own numbers.
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