Auto Loan Payoff Calculator
Find out how much sooner you'd pay off your car loan, and how much interest you'd save, by adding extra principal payments. Compare an extra monthly amount or a one-time lump sum against your standard schedule, and check whether your loan's financing type actually lets early payments save you anything.
- Interest Saved
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- Paid Off
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- New Payoff Date
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- Monthly Payment
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- Total Interest (Standard Schedule)
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- Total Interest (With Extra Payments)
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- Original Payoff Date
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Rates and figures last updated: August 10, 2026
Assumptions
- Whether extra payments actually shorten your loan depends on your financing type. With simple interest, the most common type, extra principal reduces the balance your remaining interest is calculated on immediately. With precomputed interest, the total interest is fixed at signing and split evenly across your payments, so extra payments generally do not reduce it.
- Extra payments must be designated as principal-only when you send them. Otherwise your servicer may apply the extra amount to your next scheduled payment instead of reducing principal, which would not produce the acceleration shown here.
- The interest rate and payment amount are assumed fixed for the life of the loan. This does not model a variable rate, a refinance, or add-ons like GAP insurance or an extended warranty rolled into the loan balance.
- Results are estimates for planning purposes only, not financial advice. Actual savings depend on your lender's exact payment application, and for a precomputed loan, on your specific loan agreement and state law.
Sources
- Federal Reserve Board, G.19 Consumer Credit release, commercial bank interest rate on 60-month new car loans, published August 7, 2026 (7.14% for Q2 2026, not seasonally adjusted).
- Consumer Financial Protection Bureau, "What's the difference between a simple interest rate and precomputed interest on an auto loan?", reviewed January 30, 2024.
Simple interest versus precomputed interest
On a simple interest loan, interest is calculated each month on whatever balance is still outstanding, so any extra dollar you put toward principal stops accruing interest immediately and for every month that follows. A precomputed, or add-on, interest loan works differently: the lender calculates the full interest charge once, at signing, based on the original loan amount and term, then splits principal and interest evenly across every payment. Paying extra on a precomputed loan generally does not reduce that fixed interest figure, which is why this calculator shows no time or interest savings when you select it, even with the same extra payment entered.
Choosing between extra monthly and a lump sum
On a simple interest loan, extra monthly principal produces a steady reduction that starts compounding immediately, while a lump sum is a good fit for a tax refund, bonus, or other windfall and matters most the earlier it's applied, while the balance and remaining term are still large. Either way, confirm with your lender that the extra amount is applied directly to principal on the day you send it, not held toward your next scheduled payment.
Worked example
A $25,000 loan at 7.14% for 60 months, simple interest, with an extra $50 applied to principal every month.
The standard monthly payment works out to $497. Left alone, the loan pays off in 60 months with $4,801 in total interest. Adding $50 extra to principal every month pays it off in 54 months instead, 6 months early, cutting total interest to $4,267, a savings of about $534.
Frequently asked questions
Does paying off a car loan early actually save money?
It depends on your financing type. Most auto loans use simple interest, where paying early reduces the balance your remaining payments accrue interest on, so yes, it saves money, and the earlier in the loan you do it, the more you save. A smaller number of loans use precomputed interest, where the total interest charge is fixed at signing, and paying early typically doesn't reduce it. Check your loan agreement, or select the financing type above, to see which case applies to you.
How do extra payments work in this auto loan payoff calculator?
Enter an extra amount above and this calculator adds it to your regular monthly principal payment for every month of the loan, then re-runs the full amortization schedule to show the new payoff date and total interest. It compares that accelerated schedule directly against your standard one, rather than estimating the difference from a shortcut formula.
What amortization method does this auto loan calculator use?
For a simple interest loan, it uses the standard fixed-rate amortization formula to set your monthly payment, then rebuilds the schedule month by month, tracking interest and principal separately. For a precomputed interest loan, it uses the add-on method lenders actually use: total interest is calculated once as principal times rate times loan term, then divided evenly across every payment.
How does a one-time lump sum payment affect my car loan payoff?
Select the lump sum method above, enter the amount, and choose which payment number it lands on, for example payment 6 for six months in. On a simple interest loan, the calculator applies that entire amount to principal in that one month and re-runs the schedule from there, showing the new payoff date and interest saved. The earlier in the loan the lump sum lands, the more interest it typically saves, since it removes principal while the most future interest is still ahead of it.
Can I use this to model biweekly car loan payments?
Not as an exact biweekly schedule, but you can approximate one. A biweekly plan collects half your payment every two weeks, which works out to 13 monthly payments a year instead of 12, the equivalent of one extra monthly payment spread across the year. Divide your monthly payment by 12 and enter that as your extra monthly amount above to see roughly the same effect, though it won't match a true biweekly simulation exactly since the timing of each payment differs.
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