FINANCIAL · LOAN PAYOFF EXTRA PAYMENT

Loan Payoff Extra Payment Calculator

Calculate how extra monthly payments reduce payoff time and total interest on any installment loan — auto, personal, or student.

Loan Details

Remaining amount owed on the loan.

Months left on the loan (e.g. 36, 48, 60).

Extra Payment

Additional principal paid each month on top of your regular payment.

02 You Save
Interest saved
$144.59
5 mo sooner
03 Comparison
Scheduled payment / mo$304.22
Payoff time (no extra payment)36 months
Payoff time (with extra payment)31 months
Total paid (no extra payment)$10,951.88
Total paid (with extra payment)$10,807.29

Assumes extra payments are applied to principal immediately each month. Confirm with your lender that prepayment penalties do not apply.

About This Calculator

See how making an extra monthly payment reduces the total interest and shortens the payoff time on any installment loan — auto loan, personal loan, student loan, and more. Enter your current balance, APR, remaining term, and extra payment amount.

How It Works

The calculator computes your scheduled monthly payment from your current balance, rate, and remaining term. It then runs two amortization schedules: one with no extra payment (baseline) and one with your extra payment applied to principal each month. The difference in payoff months and total interest shows exactly what you save.

The Formula

PMT = B × r(1+r)^n / [(1+r)^n − 1]

PMT
Scheduled monthly payment
B
Remaining loan balance
r
Monthly interest rate = APR / 12 / 100
n
Remaining term in months

Frequently Asked Questions

How do extra payments save so much interest?
Each extra dollar applied to principal reduces the balance on which future interest accrues. Early in a loan, a large share of your payment is interest — extra principal payments accelerate the equity curve and cut the compounding effect of interest.
Can I make extra payments on my loan?
Most installment loans allow extra payments, but some have prepayment penalties. Check your loan agreement or contact your lender before starting extra payments to ensure they're applied to principal.
Does this work for student loans?
Yes. Enter your current balance, interest rate, remaining months, and desired extra payment. For income-driven repayment plans or forgiveness programs, a student-loan-specific calculator or financial advisor is more appropriate.
What if I can only occasionally make extra payments?
This calculator assumes a fixed extra payment every month. For lump-sum payments or irregular extra payments, the actual interest savings will differ but follow the same principle.