Calculate monthly payments, total interest, amortization schedule & the effect of extra payments
M = P × [r(1+r)n] / [(1+r)n − 1]
| Year | Principal | Interest | Extra | Balance |
|---|---|---|---|---|
| Adjust inputs to see results | ||||
The free Mortgage Repayment Calculator helps you estimate your monthly mortgage payment, total interest cost, and full amortization schedule. Enter the loan amount, interest rate, term and any extra monthly payments to see how quickly you can pay off the mortgage and how much interest you will save.
Begin by configuring the parameters that match your mortgage:
Results update automatically as soon as you change any input. The application uses the standard amortising loan formula:
M = P × [r(1+r)n] / [(1+r)n − 1]
Where P is the principal, r is the monthly interest rate, and n is the total number of monthly payments. You can explore different scenarios in real time simply by adjusting the values above.
After calculation, the app displays three core metrics under the Results section:
Beyond the standard calculations, the app includes two powerful tools:
Tip: Try increasing the Extra Monthly Payment to see how much interest you can save and how many years you can shave off the mortgage.
Goal: Estimate the monthly payment and lifetime interest cost of a typical home loan.
Approximate results: Monthly Payment ≈ $1,703 | Total Interest ≈ $313,000 | Total Paid ≈ $613,000
In the early years most of each payment goes toward interest; later the principal portion grows, illustrating the classic amortization curve.
Goal: See the impact of adding a modest extra monthly payment.
You can typically cut several years off the term and save tens of thousands in interest, depending on the exact rate and starting balance.
Not Professional Advice: This calculator is provided as an estimation and educational tool and does not constitute professional financial, mortgage or tax advice. Actual mortgage products may include fees, insurance, taxes, variable rates, or other charges not modelled here. Consult a qualified mortgage advisor or lender for advice tailored to your situation.
Assumptions: Calculations assume a fixed interest rate for the entire term, monthly payments, regular extra payments applied at the end of each month, and no additional fees, taxes, or escrow. Early-payoff results are approximate and ignore any prepayment penalties that may apply in your jurisdiction.
Estimation Purposes Only: The year-by-year table and chart are illustrative. Real-world mortgages can involve rate changes, payment holidays, refinancing, or other factors not fully captured here.
Please email all suggestions for improvements and any bug reports to: mortgagerepaymentcalc@personalfinances.me, thank you.