Mortgage Calculator
Estimate the principal-and-interest payment for a fixed-rate mortgage scenario. Enter the loan amount, annual rate, and term to see the monthly payment, total interest, and total repayment. This focused mortgage calculator intentionally keeps the formula understandable and does not pretend to know property tax, homeowners insurance, HOA dues, private mortgage insurance, closing costs, or changing lender rates. Use the estimate to compare terms before checking a full lender quote. Values stay in the browser.
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Add to Chrome — freeWhat it does
- Monthly principal and interest
- Total interest
- Term comparison
- Local formula
How to use Mortgage Calculator
- 1
Enter the loan amount
Use the mortgage principal after your down payment rather than the property's full asking price.
- 2
Choose rate and term
Enter the annual rate and repayment term; the calculator assumes a fixed rate and monthly schedule.
- 3
Add omitted costs elsewhere
Keep tax, insurance, PMI, HOA, and closing costs separate because this page does not estimate them.
How it works
Build the complete housing budget
Add property tax, insurance, HOA dues, maintenance, utilities, closing costs, and an emergency reserve beside the principal-and-interest result. The displayed payment is one line of a housing budget, not an affordability limit. Keep the rate, loan amount, term, and down-payment assumptions with the scenario so another quote can be compared fairly.
The mortgage estimate uses the same standard amortization equation as a fixed-rate loan. Monthly rate is annual percentage divided by 12 and 100; months are years times 12. The page computes payment, multiplies it by the number of months for scheduled total repayment, and subtracts principal for scheduled interest. It does not build an escrow model or calculate an APR from fees.
What to add to a budget
Use this result as one line in a housing budget. Add tax, insurance, maintenance, HOA, utilities, closing costs, and a realistic emergency reserve. A lender's disclosure or amortization schedule should control any final decision, especially when the rate, payment frequency, or prepayment rules differ from these assumptions.
Principal is not the purchase price
Housing-budget checklist
Record the down payment, loan amount, rate, term, tax, insurance, HOA, maintenance, and closing-cost assumptions separately. Review the complete monthly housing budget rather than treating principal and interest as the maximum affordable payment. If the loan has points, adjustable periods, extra payments, or a balloon, request a lender-produced amortization schedule because this fixed-rate estimate will not model those changes.
The loan amount is the amount financed after a deposit or down payment. If you enter the property's full price instead, the payment will be overstated. Points, lender credits, closing costs rolled into the loan, and a down-payment assistance program can change the actual principal. Keep those inputs separate and ask for a complete loan estimate before treating the result as an affordability limit.
The calculator also does not model an initial interest-only period, a final balloon, refinancing, or extra principal payments. Those choices can materially change both the payment path and the balance at the end of a term. Ask for a complete amortization schedule whenever a mortgage structure is more complicated than fixed monthly payments.
Examples
Comparing a 30-year scenario
The displayed payment is not a complete monthly housing cost.
Comparing a shorter term
The tradeoff is useful only if the shorter payment fits the household budget.
Frequently asked questions
Does the mortgage calculator include property tax and insurance?
No. It calculates principal and interest only. A real housing payment may also include property tax, homeowners insurance, mortgage insurance, HOA dues, and escrow changes. Add those separately using local figures, and confirm the complete payment with the lender before making an offer or budget commitment.
Is the mortgage rate fixed in this estimate?
Yes. The formula assumes the annual rate remains unchanged for the full term and payments occur monthly. Adjustable-rate mortgages, discount points, refinancing, extra payments, and lender rounding behave differently. Run a fixed-rate scenario as a comparison, not as a prediction of a variable loan.
Why does a 15-year mortgage usually cost less interest?
Principal is repaid over fewer months, so there are fewer periods in which interest can accrue. The monthly payment is usually higher because each payment carries more principal. Compare total cost with affordability, reserves, and the value of keeping cash available rather than selecting a term by interest alone.