How is a monthly mortgage payment calculated?

For a fixed-rate amortizing loan, the monthly payment is P × r × (1+r)^n ÷ ((1+r)^n − 1), where P is the loan principal, r is the monthly interest rate (annual rate ÷ 12), and n is the total number of monthly payments (years × 12).

Does this mortgage calculator include taxes and insurance?

The base result covers principal and interest only. Property taxes, homeowners insurance, HOA fees, and private mortgage insurance vary by location and lender, so enter them separately if your lender quotes an escrow amount.

Is it worth making extra mortgage payments?

Extra payments reduce the principal earlier, which cuts total interest and shortens the loan term. Whether that beats investing the same money depends on your mortgage rate, expected investment returns, and liquidity needs. The comparison table on this page shows the interest saved and months saved for different extra payment amounts.

What loan terms do most borrowers choose?

In the United States, 30-year fixed-rate mortgages are the most common, followed by 15-year fixed loans. A 15-year term usually carries a lower rate and far less total interest, but a higher monthly payment.

Mortgage & loan tool

Mortgage Calculator

Estimate your monthly payment, total interest, and payoff date for a fixed-rate loan. Add an extra monthly payment to see how much interest you save and how many months you shave off the term — all results update instantly in your browser.

Monthly payment (P&I) $0

Total interest paid $0

Total of payments $0

Payoff time 0 yrs 0 mo

Interest saved by extra payments $0

Time saved 0 mo

Payment breakdown

Principal vs. Interest

Over the full loan term, every dollar you repay is either principal (the amount borrowed) or interest (the lender's charge). The chart shows the split for your current inputs.

Principal Interest

Extra payment comparison (same loan, different monthly extras)
Extra / month	Monthly total	Total interest	Payoff	Saved

FAQ

Mortgage Payment Questions

How is the monthly payment calculated?

Fixed-rate amortizing loans use the formula M = P × r × (1+r)ⁿ ÷ ((1+r)ⁿ − 1). P is the principal, r is the monthly rate (annual rate ÷ 12 ÷ 100), and n is the number of monthly payments (years × 12). Early payments are mostly interest; later payments are mostly principal.

Are taxes and insurance included?

No. This calculator covers principal and interest. Property taxes, homeowners insurance, HOA dues, and PMI are location- and lender-specific, so add your lender's escrow estimate on top of the P&I figure shown here.

Is making extra payments worth it?

Every extra dollar shortens the principal earlier, so total interest falls and the payoff date moves forward. The comparison table quantifies it for your rate and term. Whether that beats investing the same cash depends on your expected returns and need for liquidity — some mortgages also carry prepayment penalties, so check your note.

15-year or 30-year loan?

A 15-year term usually has a lower rate and dramatically less total interest, but a higher required monthly payment. Run both terms in the calculator and compare the "Total of payments" figure — that is the true lifetime cost difference.

What about adjustable-rate mortgages?

ARM payments change when the rate resets, so a single fixed formula cannot describe the whole loan. This calculator is accurate for fixed-rate loans and gives a reasonable starting estimate for ARMs during the initial fixed period.

Does anything I type leave my browser?

No. All math runs locally in JavaScript. No amounts, rates, or personal details are uploaded, stored, or shared.

Disclaimer

Mortgage Estimate Disclaimer

Results are educational estimates only and are not loan offers, financial, tax, or legal advice. Actual payments depend on lender terms, escrow, PMI, fees, and rate locks. Confirm exact figures with your lender.