AI Calculator Tool

Free Online Mortgage Calculator

Enter home price, down payment, interest rate, and loan term to see your estimated monthly payment and total interest. Figures are for principal and interest only—add taxes and insurance for your full housing budget.

Estimates principal and interest only. Add taxes, insurance, and HOA for your full housing payment.

Try an example

20% of $300,000 · Loan $240,000

Monthly P&I

$1,517

Total paid

$546,107

Total interest

$306,107

How this mortgage calculator works

We subtract your down payment from the home price to get the loan amount, then apply the standard fixed-rate amortization formula for your monthly principal-and-interest payment.

This estimate does not include property taxes, homeowners insurance, HOA fees, or PMI. Lenders may round differently, so treat the result as a planning number—not a binding quote.

Tip: Run the same home price with a 15-year and 30-year term side by side. The shorter loan costs more per month but far less interest over time.

Already know your loan amount? Try the EMI calculator for monthly payment and amortization.

Worked examples

Sample numbers you can try in the calculator above. Your lender's quote may differ slightly.

  • $300,000 home, 20% down

    A common first-buyer scenario. Total interest over 30 years is roughly $305,000 on top of the $240,000 principal.

    $240,000 loan · 6.5% APR · 30 years

    Monthly P&I: About $1,516/month P&I

  • 15-year vs 30-year on the same loan

    The 15-year payment is higher each month, but you pay off the home sooner and spend much less on interest overall.

    $240,000 at 6.5%

    Monthly P&I: 15 yr ≈ $2,089/mo · 30 yr ≈ $1,516/mo

  • Smaller down payment

    A 10% down payment raises the financed amount to $360,000. You may also owe PMI until you reach 20% equity—not included here.

    $400,000 home · 10% down · 7% · 30 years

    Monthly P&I: About $2,394/month P&I

  • Refinance check

    Useful when comparing a new rate to your current loan. Confirm payoff date and closing costs with your lender.

    $200,000 balance · 5.5% · 25 years remaining

    Monthly P&I: About $1,228/month P&I

Frequently asked questions about the mortgage Calculator

  • What does the monthly mortgage payment include?

    This tool shows principal and interest (P&I) only. Your full payment often also includes property taxes, insurance, HOA dues, and PMI if your down payment is under 20%.

  • How is the monthly payment calculated?

    We use the standard fixed-rate formula on the loan amount (price minus down payment), your annual rate divided by 12, and the number of months in the term.

  • Should I choose a 15-year or 30-year mortgage?

    A 15-year loan has higher monthly payments but less total interest. A 30-year loan lowers the monthly bill but costs more interest over time. Compare both in the calculator.

  • Does a larger down payment reduce my payment?

    Yes. Putting more down lowers the amount you borrow, which reduces both the monthly payment and total interest.