Extra payment loan calculator
See how much interest you save by making an extra payment on your loan, shortening the term or lowering the payment, with fixed payments or constant amortization.
Extra payment: shorter term or lower payment?
Everything happens on your device: nothing is uploaded to the internet.
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Extra payment loan calculator: what it is for
Enter the loan balance, the monthly interest rate, the payments left and the extra payment. The calculator compares three scenarios (no extra payment, shorter term and lower payment) and shows the new payment, the number of payments, the total paid and the interest saved in each, for fixed-payment (Price) or constant-amortization (SAC) loans.
How to use
- Choose fixed payment or constant amortization.
- Type the balance, interest and payments.
- Enter the extra amount and compare.
When to use it
- Decide where to use a bonus or tax refund.
- Pay down a mortgage faster.
- Pay off a car loan early.
Frequently asked questions
Is it better to shorten the term or lower the payment?
Shortening the term almost always saves more interest, because the balance stops accruing interest sooner. Lowering the payment gives your monthly budget more room.
Where do I find the balance and the rate?
On your lender's statement or app, in the loan contract, or by asking the lender for a payoff statement. Use the monthly effective interest rate (yearly rate ÷ 12 for most US loans).
Can my lender charge for extra payments?
Most US mortgages and auto loans allow extra principal payments with no penalty, but some loans have a prepayment penalty. Check your contract and tell the lender to apply the extra amount to principal.
Is it really free?
Yes, 100% free. No sign-up, no subscription and no usage limits. All Tools123 tools are free and run right in your browser.