Does the extra payment go toward interest or principal?

The extra payment goes straight to your principal (the amount you owe). It does not pay interest. By lowering your principal faster, you reduce the interest that builds up each month. This is how extra payments save you money.

What happens if I set the extra payment amount to $0?

If you set the extra payment to $0, the calculator shows your original loan schedule with no changes. This is useful if you just want to see your standard monthly payment, total interest, and payoff date without any extra payments.

What does Years Remaining mean and how is it different from the original loan term?

The original loan term is the full length of the loan when you first got it. Years remaining is how many years you still have left to pay. For example, if you took out a 30-year mortgage 5 years ago, your original term is 30 and your years remaining is 25. This lets the calculator figure out your current balance.

Can I use this calculator for a mortgage, car loan, or student loan?

Yes. This calculator works for any fixed-rate loan . That includes mortgages, auto loans, personal loans, and student loans. As long as your loan has a fixed interest rate and regular monthly payments, this tool will give you accurate results.

What is the difference between monthly and one-time extra payments?

Monthly means you add the extra amount to every single payment for as long as you choose. One-time means you make a single lump-sum payment on a specific date. Monthly extra payments usually save more interest over time because they reduce your balance continuously.

How does the Compare Extra Payment Amounts section work?

This section shows three scenarios side by side: half your extra payment amount, your chosen amount, and double your amount. For each one, it shows the interest saved, time saved, and new payoff date. This helps you decide how much extra to pay each month.

Why does the calculator show two columns in the amortization table?

The table shows your original schedule on the left and your extra payment schedule on the right. This lets you compare them side by side for each month or year. You can see how your balance, interest, and principal differ with and without extra payments.

What is the difference between the annual summary and monthly breakdown views?

The annual summary combines all 12 months of each year into one row. The monthly breakdown shows every single month as its own row. The annual view is easier to scan, while the monthly view gives you more detail.

Can I make extra payments for only part of my loan and then stop?

Yes. Use the Extra Payment Start and Extra Payment End fields to set a time window. The calculator will only apply extra payments during that period. After the end date, it goes back to your normal monthly payment.

Does this calculator account for taxes, insurance, or escrow?

No. This calculator only handles principal and interest (P&I) . It does not include property taxes, homeowner's insurance, PMI, or escrow payments. Your actual total monthly payment to your lender may be higher than what the calculator shows.

How do I download my results?

Below each chart, you will find buttons to download the chart as a PNG image , SVG vector file , or CSV spreadsheet . Click the button for the format you want, and the file will download to your device.

What does the Step-by-Step Solution section show?

It walks you through the math behind your results. It shows how the monthly interest rate is calculated, how your standard payment is found, your current balance, and how the extra payments change your total interest and payoff timeline. This helps you understand exactly where the numbers come from.

Does this calculator work for adjustable-rate loans?

No. This tool is designed for fixed-rate loans only. If your loan has an adjustable or variable interest rate, the results will not be accurate because the rate can change over time.

What happens if my extra payment is more than my remaining balance?

The calculator is smart about this. If your extra payment would bring your balance below zero, it only applies enough to pay off the remaining balance. You will never overpay in the results.

How accurate are the results from this calculator?

The results are very accurate for fixed-rate loans based on the numbers you enter. However, your actual loan may have small differences due to rounding, payment processing dates, or fees. Always check with your lender before making changes to your payment plan.

Finance calculators

Extra Payment Calculator

Updated Jul 13, 2026 By Jehan Wadia

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