Mortgage Calculator
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Enter a home price, down payment, interest rate and term to estimate your monthly mortgage payment, including optional property tax and insurance, plus the total interest and total cost over the life of the loan. Everything is calculated on your device.
How the mortgage payment is calculated
This calculator uses the standard amortized loan formula for fixed-rate mortgages. First it subtracts your down payment from the home price to get the loan amount, then it applies the monthly rate (annual rate divided by twelve) across the full number of monthly payments (term in years multiplied by twelve). The result is the fixed principal-and-interest payment that clears the balance exactly at the end of the term.
If you add annual property tax and home insurance, the tool divides each by twelve and adds them on top of principal and interest. That gives an estimate closer to the real monthly outlay lenders often quote as PITI: principal, interest, taxes and insurance.
Why down payment, rate and term matter
Your down payment directly shrinks the amount you borrow, which lowers both the monthly payment and the lifetime interest. A larger deposit can also help you qualify for better rates and avoid mortgage insurance in many markets.
The interest rate and term work together to shape total cost. A 30-year term keeps monthly payments low but stretches interest across three decades, while a 15-year term raises the monthly figure yet can cut total interest dramatically.
- Bigger down payment: smaller loan, less interest overall
- Lower rate: reduces both the monthly payment and total interest
- Shorter term: higher monthly payment but far lower lifetime interest
Reading the total interest figure
The total interest line is often the most eye-opening number. Because early mortgage payments are weighted heavily toward interest, a long loan can see interest rival or exceed a large share of the principal borrowed. Seeing that figure in plain numbers makes it easier to judge whether a shorter term or a slightly larger down payment is worth it.
Use the calculator to compare offers side by side. Enter two scenarios with different rates or terms and watch how the monthly payment and total cost shift, so you can decide with real numbers rather than guesswork.
Frequently asked questions
What loan amount does the tool actually use?
It borrows the home price minus your down payment. If you leave the down payment blank, the full home price is treated as the loan amount.
How is total cost worked out?
It multiplies the full monthly payment (including any tax and insurance) by the number of months in the term, giving the total of all payments you would make.
Can I use it for a refinance?
Yes. Enter your remaining balance as the home price with a zero down payment, then set the new rate and remaining term to compare against your current loan.
What if I enter a zero percent rate?
The calculator simply divides the loan amount evenly across all the months, which is useful for interest-free or promotional financing scenarios.
Does it account for extra payments?
No. It assumes level, scheduled payments. Extra principal payments would reduce interest and shorten the term beyond what this estimate shows.
Is the result a guaranteed quote?
No. It is an estimate for planning. Actual lender quotes may include fees, escrow rules, insurance and rate adjustments that vary by location and lender.
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