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Mortgage Calculator

Estimate your monthly mortgage payment, total interest and total cost over the life of the loan.

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Monthly payment
$1,798.65
Total interest
$347,514.57
Total paid
$647,514.57

How it works

This calculator estimates the principal-and-interest (P&I) portion of a fixed-rate mortgage payment, plus the total interest and total amount paid over the life of the loan. It is built for home buyers sizing up a price range, owners weighing a refinance, and anyone comparing a 15-year against a 30-year term. Enter the loan amount — the purchase price minus your down payment — not the full home price.

The monthly payment follows the standard amortization formula M = P × r × (1 + r)ⁿ / ((1 + r)ⁿ − 1), where P is the loan amount, r the monthly rate (annual rate ÷ 12 ÷ 100) and n the number of monthly payments (a 30-year term is 360). Because interest is charged on the outstanding balance, early payments are mostly interest; the principal share grows month by month until the loan is retired.

A fully worked example: $300,000 at 6% over 30 years. The monthly rate is 0.06 ÷ 12 = 0.005 and (1.005)³⁶⁰ ≈ 6.0226, so M = 300,000 × 0.005 × 6.0226 ÷ (6.0226 − 1) ≈ $1,798.65. Across 360 payments that totals $647,514.57, of which $347,514.57 is interest — more than the amount borrowed, which is normal at this rate and term. The same loan over 15 years costs $2,531.57 a month but only $155,682.69 in interest, a lifetime saving of $191,831.88.

Read the result as a floor, not your full housing cost. Lenders collect property taxes and homeowners insurance through escrow on top of P&I, a down payment under about 20% usually adds PMI (private mortgage insurance), and HOA dues are billed separately — all of which vary by location and are excluded here. The fixed payment also only holds for fixed-rate loans; with an adjustable-rate mortgage it applies to the initial fixed period only.

Country versions: United States, United Kingdom, Canada, Australia.

Frequently asked questions

Does this include taxes and insurance?
No — it computes principal and interest only. Property tax, homeowners insurance, PMI and HOA dues come on top and vary a lot by location, often adding several hundred dollars a month. Ask your lender for a full escrow estimate to budget the real monthly cost.
Should I enter the home price or the loan amount?
The loan amount: purchase price minus your down payment. A $375,000 home bought with 20% down means a $300,000 loan. Entering the full price overstates the payment unless you are financing 100% of it.
How much does a 15-year term save versus 30 years?
On a $300,000 loan at 6%, the 30-year payment is $1,798.65 with $347,514.57 of lifetime interest; the 15-year payment is $2,531.57 but interest drops to $155,682.69. That is $191,831.88 saved in exchange for roughly $733 more per month.
What is PMI and when do I pay it?
Private mortgage insurance is typically required on conventional loans when the down payment is below 20%, and it protects the lender, not you. It usually costs a fraction of a percent of the loan balance per year and can be removed once you build enough equity. This calculator does not include it.
Should I use the interest rate or the APR?
Use the interest rate — that is what the monthly payment is actually computed from. The APR bundles in closing costs and points, so it runs higher; it is the right number for comparing offers between lenders, not for estimating the payment.
Why is the total interest more than I borrowed?
Over 360 monthly payments, interest accrues on a large balance for a very long time — at 6% over 30 years it adds up to about 116% of the principal. Extra principal payments made early cut it disproportionately, because they reduce the balance every later month’s interest is charged on.
Is my data uploaded?
No — the calculation runs in your browser and nothing you enter is sent anywhere.

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