Tools / Simulators

Extra Payment Loan Calculator

See how extra monthly, yearly, or one-time payments can reduce your loan interest and payoff time.

This is an extra payment calculator and loan payoff calculator in one. It works like an amortization calculator for a mortgage extra payment, a car loan payoff, or a student loan extra payment — enter your loan, add extra payments, and compare the results. Everything runs in your browser. No signup.

Loan details

Enter the loan you want to test. Estimates are fine.

The yearly rate on your loan, e.g. enter 6.5 for 6.5%.

Loan term

A 5-year loan is 5 years and 0 months. A 30-month loan is 0 years and 30 months. Total term must be 3–360 months.

Loan start date

Used to estimate payment dates and payoff timing.

Extra monthly payment (optional)

An extra amount added every month on top of your required payment.

Extra yearly payment (optional)

Applied once per year in the chosen month — good for a tax refund or bonus.

Extra one-time payment (optional)

A single extra payment in a specific month and year.

This calculator runs entirely in your browser. Nothing is saved on a server.

Before you commit

Can you safely afford this extra payment?

This calculator shows the loan math. Balance On Hand helps you see whether that extra payment fits your real future cash flow before you commit.

Before you send extra money to a lender, make sure your upcoming bills, food, gas, savings, and emergency cushion still work.

How to Use This Calculator

This calculator helps you compare your loan with and without extra payments.

Start by entering your loan amount, interest rate, loan term, and loan start date. Then choose whether you want to test an extra monthly payment, an extra yearly payment, or a one-time extra payment.

After you enter your information, the calculator estimates your regular monthly payment, your original payoff date, your new payoff date, total interest, and how much interest you may save.

The results are estimates. Your actual lender may calculate interest, fees, payment timing, or payoff amounts differently.

  1. Enter your loan amount. This is the amount you borrowed or the current balance you want to test.
  2. Enter your interest rate. Use the yearly interest rate on your loan. For example, enter 6.5 for 6.5%.
  3. Enter your loan term. Use years, months, or both. For example, a 5-year loan is 5 years and 0 months. A 30-month loan can be entered as 0 years and 30 months.
  4. Choose your loan start date. This helps the calculator estimate payment dates and payoff timing.
  5. Add extra payments. You can test an extra monthly payment, an extra yearly payment, a one-time extra payment, or a combination of all three.
  6. Review the results. Compare the original loan against the loan with extra payments. Look at the new payoff date, interest saved, and total amount paid.

What These Terms Mean

Loan amount
Loan amount means the amount borrowed or the balance you want to calculate. For a new loan, use the original loan amount. For an existing loan, you can use your current payoff balance if you want a closer estimate from today forward.
Interest rate
Interest rate is the yearly percentage rate charged by the lender. This calculator uses the annual interest rate to estimate monthly interest.
Loan term
Loan term is how long the loan is scheduled to last if you only make the required payments. A 5-year loan is 60 months. A 30-year loan is 360 months.
Required monthly payment
Required monthly payment is the estimated regular payment needed to pay off the loan by the end of the original term. Extra payments are added on top of this amount.
Principal
Principal is the loan balance you still owe, not including future interest. Extra payments usually reduce principal, which can lower the amount of interest you pay over time.
Interest
Interest is the cost of borrowing money. On many loans, interest is calculated from the remaining balance, so reducing the balance faster can reduce future interest.
Extra monthly payment
An extra monthly payment is an additional amount paid every month on top of the required monthly payment. For example, if your required payment is $400 and you add $100 extra monthly, the calculator estimates payments as $500 per month.
Extra yearly payment
An extra yearly payment is an additional payment made once per year. For example, you may want to test using part of a tax refund, work bonus, or yearly savings toward the loan.
One-time extra payment
A one-time extra payment is a single additional payment made in a specific month and year. This can help you test what happens if you make one larger payment toward the loan.
Payoff date
Payoff date is the estimated month and year when the loan balance reaches zero.
Interest saved
Interest saved is the difference between the estimated interest without extra payments and the estimated interest with extra payments.
Amortization schedule
An amortization schedule is a month-by-month table showing how each payment is split between principal and interest, and how the balance changes over time.

Important: Extra payments usually do not lower your required monthly payment unless your lender recasts, refinances, or recalculates the loan. In most cases, extra payments help you pay the loan off sooner and reduce total interest.

Before You Make Extra Payments

Paying extra on a loan can save interest, but it should not leave you short on rent, food, gas, insurance, medical costs, or emergency savings.

Balance On Hand helps you look forward before you commit. You can add your income, bills, spending estimates, savings goals, and loan payments to see whether extra payments fit your real cash flow.

Calculator math is helpful. Future balance clarity is better.

Test your cash flow in Balance On Hand