How it works
A fixed-rate amortizing mortgage uses a level principal-and-interest payment. Early payments contain more interest because the outstanding balance is larger; principal repayment increases as the balance declines.
The formula
Keep currency, units and time periods consistent. Percentage inputs use percentage points (enter 5 for 5%). Results are rounded only for display; tiny nonzero values may use scientific notation. Undefined ratios are shown as unavailable.
$320,000 at an assumed 6.5% annual interest over 30 years gives $2,022.62 monthly P&I, $728,142.36 total scheduled payments and $408,142.36 interest. Taxes, insurance and HOA are separate.
Calculation method
The annual nominal interest rate is divided by the selected payment frequency. Weekly and two-weekly choices are ordinary equivalent amortization schedules, not accelerated half-monthly payments. Monthly equivalents allow comparison.
Interpretation
Extra monthly principal is converted to an equal annual amount over the chosen payment frequency. The payoff schedule caps the final payment at the remaining balance. No prepayment penalty, PMI, escrow changes or lender rounding is assumed.
Limitations
All rents, values, vacancy, expenses and financing terms are your assumptions. Figures exclude income tax and appreciation. Inputs stay in your browser. These calculations do not predict loan approval or investment outcomes.
Method and reference sources
Method and content checked 2026-09-20. These sources provide background, not endorsement or professional certification. The formula and limitations above define this calculator.
- CFPB — Principal and interest versus total mortgage paymentPrincipal and interest exclude taxes, insurance and other housing charges unless those amounts are added separately.
Frequently asked questions
Does the principal-and-interest result equal the total housing bill?
No. Property taxes, insurance, mortgage insurance and association charges may add to the total. Review the payment breakdown and your lender’s actual terms.
What is a worked example for Mortgage Payment?
$320,000 at an assumed 6.5% annual interest over 30 years gives $2,022.62 monthly P&I, $728,142.36 total scheduled payments and $408,142.36 interest. Taxes, insurance and HOA are separate.