Amortization Calculator — FAQ

Back to the tool

Frequently asked questions

How much interest do overpayments actually save?

More than most people expect. On a 30-year, €300,000 mortgage at 4%, an extra €200 per month saves roughly €50,000 in total interest and cuts the loan term by about 5 years. The earlier in the loan you start overpaying, the larger the saving — because early payments reduce the balance that interest accumulates on for the remaining decades. Use the overpayment field in the calculator to see the exact saving for your numbers.

What interest rate should I enter — the APR or the nominal rate?

Enter the nominal annual interest rate, not the APR (Annual Percentage Rate). The APR includes fees and other costs that aren't part of the monthly payment calculation. Your mortgage agreement will show both; use the "interest rate" or "nominal rate" figure. If you enter the APR, your monthly payment estimate will be slightly high.

Why is most of my early payment going to interest?

This is how amortization works. Your monthly payment is fixed, but the interest portion is calculated on the outstanding balance — which is highest at the start of the loan. Early payments cover a lot of interest and very little principal. As the balance falls, more of each payment goes to principal. By the final year, almost all of each payment is principal.

Does the calculator include property tax, insurance, and PMI?

No. It calculates principal and interest only. Property tax, homeowner's insurance, and PMI (private mortgage insurance) are additional costs that vary by location, lender, and loan-to-value ratio. Your lender's disclosure documents will show the full monthly escrow amount. Add those figures to the calculator's monthly payment to get your total housing cost.

Can I use this for loans other than mortgages?

Yes. The amortization formula is the same for any fixed-rate, equal-payment loan: car loans, personal loans, student loans. Enter the loan amount, interest rate, and term in years (convert months to fractional years if needed). The schedule will be correct for any standard amortising loan.

What does "remaining balance" in the schedule mean exactly?

It's the outstanding principal after that month's payment has been applied. This is also called the "payoff amount" — the lump sum you would need to pay to fully close the loan at that point. Note that lenders may charge early repayment fees; the balance shown here is the pure mathematical payoff, before any penalties.

Is my financial data sent anywhere?

No. All calculations happen in your browser. The loan amount, interest rate, and term you enter are never transmitted to a server or stored. Closing the tab clears everything.