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US Mortgage Calculator
Built to US rules: interest compounds monthly, and the standard mortgage is the 30-year fixed — one rate locked for the entire loan. The monthly payment a lender quotes bundles more than the loan itself, so this tool breaks out principal and interest, property taxes, homeowners insurance, and HOA dues separately.
Your home and loan
Your monthly payment
| Principal & interest6.5% ÷ 12 per month, over 360 payments | $2,149.03 |
| Property taxes$5,100.00 per year ÷ 12 | $425.00 |
| Homeowners insurance$1,800.00 per year ÷ 12 | $150.00 |
| HOA duesMonthly, as entered | $0.00 |
| Total monthly payment | $2,724.03 |
This is an estimate, not a loan offer. Taxes and insurance are held in escrow by most lenders and change over time, so even with a fixed rate the total payment isn't fixed forever. PMI is not included — with less than 20% down, most conventional loans require it until you reach about 20% equity. Buying in Canada instead? Use the Canada Mortgage Calculator — Canadian mortgages compound differently.
How the math works
A US mortgage compounds monthly, so each month interest is charged at one-twelfth of the annual rate on the remaining balance. The fixed payment that pays the loan off exactly at the end of the term is:
Taxes and insurance aren't part of the loan, but most lenders collect one-twelfth of the yearly amounts with each payment and hold them in an escrow account, paying the bills when they come due. That's why the payment you actually make — often called PITI (principal, interest, taxes, insurance) — is higher than the loan payment alone:
Early in the loan, most of the principal-and-interest payment is interest, because the balance is at its largest. In the worked example, the very first payment is $1,841.67 of interest and only $307.36 of principal; by the final years that split has nearly reversed. This is amortization, and it's why extra principal payments early in the loan save so much interest.
Worked example (in USD)
A $425,000 home with $85,000 down (20%) — a $340,000 loan at 6.5% on a 30-year fixed, with property taxes of $5,100/year and insurance of $1,800/year:
Principal & interest: $340,000 × (6.5% ÷ 12) ÷ (1 − 1.0054167−360) = $2,149.03 a month
Taxes: $5,100 ÷ 12 = $425 · Insurance: $1,800 ÷ 12 = $150
Total monthly payment: $2,149.03 + $425 + $150 = $2,724.03
Total interest over 30 years: $433,651.26 — about $1.28 of interest for every $1 borrowed. The same loan on a 15-year term would cost $2,961.77 a month in principal and interest, but only $193,117.71 in total interest — a saving of about $240,534.
Common gotchas
- A fixed rate doesn't mean a fixed payment. Principal and interest never change on a fixed-rate loan, but property taxes and insurance premiums do — usually upward. When they rise, your escrow portion rises with them, and the total monthly payment goes up even though your loan terms haven't changed.
- PMI shows up under 20% down. Private mortgage insurance on a conventional loan typically costs roughly 0.3%–1.5% of the loan amount per year, billed monthly, until you reach about 20% equity; on most conventional loans it must be removed at 78% loan-to-value. It is not included in the figures above, so a small down payment makes the real payment higher than shown. FHA loans charge their own mortgage insurance premiums, with different rules.
- Closing costs aren't in the payment. Origination fees, discount points, appraisal, title, and prepaid items typically add about 2%–5% of the loan amount at closing. A lower rate bought with points can look cheaper monthly while costing more overall if you move or refinance within a few years.
- Property taxes vary more than rates do. Effective property tax rates run from well under 0.5% of a home's value in some states to over 2% in others — on a $425,000 home that's the difference between roughly $175 and $700+ a month. Never carry one state's tax assumption into another state's house hunt.
- The 30-year term is the expensive default. Stretching the loan to 30 years minimizes the monthly payment and maximizes total interest — $433,651 on a $340,000 loan in the example. A 15- or 20-year term usually comes with a lower rate on top of the shorter schedule, which is why the interest saving is so large.
- An ARM is a different product. Adjustable-rate mortgages fix the rate only for an initial period (5, 7, or 10 years is common), then adjust it periodically. This calculator assumes a fixed rate for the whole term; don't use it to judge an ARM's risk after the fixed period ends.