Mortgage Calculator
Adjust the inputs below. Results update as you type.
How it works
A mortgage payment estimate is most useful when you separate principal-and-interest (P&I) from the full housing payment. This calculator solves for a level P&I payment on a fixed-rate amortizing loan, then lets you layer optional property tax, homeowners insurance, PMI, HOA, and a maintenance reserve so the total monthly figure is closer to what ownership actually costs.
Start with purchase price, down payment, rate, and term. The financed amount is usually price minus down payment (plus financed closing costs if you roll them in). A longer term lowers monthly P&I but raises lifetime interest; rate differences compound over 15–30 years, so prefer a real lender quote over a national average when you are close to deciding.
Use the payment breakdown and amortization schedule to see how early payments are interest-heavy and how extra principal changes payoff. Cash-to-close and five-year housing-cost estimates help stress-test affordability beyond the first month. Escrow cushions, PMI cancel rules, and ARM resets still vary by lender—treat outputs as planning estimates, not a binding quote.
Input guidance
- Home price and down payment define financed principal and cash-to-close needs.
- APR strongly affects both monthly payment and total interest over long terms.
- Add taxes, insurance, PMI, and HOA after P&I for a realistic housing budget.
The formula
Monthly principal-and-interest uses the amortizing loan formula M = P · r · (1+r)^n / ((1+r)^n − 1), where P is the loan amount, r is the monthly rate (annual rate ÷ 12), and n is the number of monthly payments (years × 12).
Worked example
On a $300,000 loan at 6.5% for 30 years: r = 0.0054167, n = 360. The monthly payment works out to about $1,896. Over the full term you repay roughly $682,600 — about $382,600 of it interest.
More examples to test
- $400,000 home, 20% down, 6.0% for 30 years: compare monthly P&I vs five-year interest paid.
- $400,000 home, 10% down, 6.75% for 30 years: observe higher payment and PMI-related cash needs.
How to interpret results
Treat the total monthly payment as a housing-budget line: start with P&I, then fill in tax, insurance, PMI, HOA, and maintenance so the figure matches how lenders and your cash flow actually look.
When this can be inaccurate
Quotes, points, escrow cushions, PMI cancellation rules, and ARM resets are not fully modeled. Closing costs and local tax assessments vary by property.
Sources
Change history
- July 2026: Expanded housing-cost guidance and clarified P&I vs full PITI scope.
- June 2026: Formula and amortization outputs quality-reviewed for publication.
Site-wide corrections also appear on the corrections log.
Compare mortgage rates from top lenders
Rates vary by credit score and lender.
Frequently asked questions
Does this include property tax and insurance?+
Yes—you can enter annual property tax, insurance, PMI, HOA, and a maintenance reserve. The headline total monthly payment combines P&I with those extras. If you leave extras at zero, you still get a clean principal-and-interest figure.
How does the loan term affect my payment?+
A longer term lowers the monthly payment but raises total interest. A 15-year loan has a much higher monthly payment than a 30-year, yet you pay far less interest overall because the balance clears faster.
What rate should I enter?+
Use the annual percentage rate (APR) your lender quotes. Even a 0.5% difference noticeably changes both the monthly payment and the lifetime interest, so use a real quote when you can.
Why is my lender payment different from this result?+
Lenders quote PITI and may use different escrow estimates, PMI formulas, or HOA amounts. Match this calculator’s extras to your quote line items, then compare P&I alone if the escrow numbers still differ.
Should I choose 15 or 30 years based on payment alone?+
No. A 15-year loan raises the payment but usually cuts total interest sharply. Pick the term you can sustain with reserves, not only the lowest monthly number.
Guided next steps
Want the full workflow? Use this calculator inside a step-by-step guide.
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Get the Home Buying Numbers Checklist
Free: Home Buying Numbers Checklist (PDF)
- Budget, down payment, and closing-cost worksheet
- Monthly payment stress-test ranges
- Refinance and rent-vs-buy decision prompts
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