Mortgage Calculator
Monthly payment, total cost & interest
How to Use
- 1Enter the home price and how much you'll pay upfront (down payment).
- 2Set the loan term in years and the yearly interest rate.
- 3Read your monthly payment instantly on the purple display.
- 4Check the tiles for loan amount, total paid and total interest.
Mortgage Formula
- Monthly paymentM = P·r·(1+r)ⁿ ÷ ((1+r)ⁿ − 1)
- Loan amountP = price − down payment
- Monthly rater = annual rate ÷ 12
- Paymentsn = years × 12
Quick Examples
Tap an example to load it above.
Everything about the Mortgage Calculator
How monthly payments are calculated and what really drives the cost of a home loan.
A mortgage is a long-term loan used to buy a home, repaid in fixed monthly instalments of principal and interest. This mortgage calculator turns four numbers, home price, down payment, term and interest rate, into your monthly payment, and shows the total you'll pay and how much of it is interest.
It's one of the most useful everyday money tools: compare two houses, see what a bigger down payment saves, or check how a 15-year term stacks up against a 30-year one before talking to a bank.
Tip: The payment shown covers principal and interest. Your real monthly cost usually adds property taxes, home insurance and sometimes PMI, so budget roughly 15 to 25% on top.
How the payment is calculated
The standard amortization formula is M = P·r·(1+r)ⁿ ÷ ((1+r)ⁿ − 1), where P is the loan amount (price minus down payment), r the monthly interest rate (annual ÷ 12) and n the number of monthly payments (years × 12). For a $240,000 loan over 30 years at 6.5%, the payment is about $1,517 per month.
What changes your payment most
- 1Interest rate
Even 0.5% makes a big difference over 30 years, so always compare offers from several lenders.
- 2Loan term
A 15-year loan has higher monthly payments but cuts total interest dramatically compared to 30 years.
- 3Down payment
Paying more upfront shrinks the loan, lowers the payment and can remove the need for PMI (usually at 20%+).
- 4Extra payments
Paying a little extra toward principal each month shortens the loan and saves thousands in interest.
Frequently Asked Questions
How is a mortgage payment calculated?
With the amortization formula M = P·r·(1+r)ⁿ ÷ ((1+r)ⁿ − 1), where P is the amount borrowed, r the monthly rate and n the number of payments. This calculator applies it instantly and also shows the total cost and interest.
Does this include taxes and insurance?
No. The result is principal and interest (P&I) only, which is what the loan formula defines. Property taxes, homeowner's insurance, HOA fees and PMI vary by location and lender, so add them on top for a full monthly budget.
15-year vs 30-year mortgage: which is better?
A 30-year term gives a lower monthly payment; a 15-year term costs more per month but usually has a lower rate and saves a huge amount of total interest. Try both terms here and compare the "Total interest" tile.
How much down payment do I need?
Many loans allow as little as 3 to 5% down, but 20% is the classic benchmark, because it usually removes private mortgage insurance (PMI) and lowers your payment. Enter different down payments here to see the effect.
Why is the total interest so high?
Interest accrues every month on the remaining balance, and early payments are mostly interest. Over 30 years that adds up, often to more than the original loan. Shorter terms, lower rates and extra principal payments all reduce it.
Is this mortgage calculator free and does it work on mobile?
Yes. It's 100% free, needs no sign-up and no download. It works in any modern browser and is fully responsive. Your numbers stay in your browser; nothing is stored or shared.