Auto Loan Refinance Calculator
Compare keeping your car loan with refinancing, including fees, remaining debt and a longer repayment term.
Your inputs
Use consistent units and periods. Defaults are examples.
Your result
Check the assumptions below before relying on a result.
Formula and method
For each loan, monthly payment = P × r / [1 − (1+r)^−n], where r is nominal annual interest/12; zero rate uses P/n. New principal = current debt + financed fees. Economic cost at month h = immediate cash fees/penalty + payments made + remaining principal. Refinance advantage = keep cost − refinance cost. The complete timeline checks the first non-negative advantage and any later reversal.
Worked example
At zero interest, 12,000 repaid over 12 months costs 1,000 per month. Refinancing it over 24 months with a 120 cash fee costs 500 per month. At month 12, keep cost is 12,000; refinance cost is 6,000 paid + 6,000 debt + 120 fee = 12,120. The smaller payment has not saved money.
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Open calculator ↗How to use this result
- Get the current payoff information and remaining term. Separate any old-loan penalty.
- Use the offered nominal interest rate and new term. APR may include fees and should not be substituted blindly.
- Allocate each new charge once: financed or paid in cash.
- Compare costs at your expected ownership date and inspect the complete timeline.
- Check full-term cash separately; a lower payment may come from a longer loan.
Questions about this calculation
Can the payment fall while the total cost rises?
Yes. Extending the term spreads principal across more payments and can leave more debt at a near-term sale date.
Why include the remaining balance?
It still must be paid when selling or replacing the loan. Comparing payments alone ignores that liability.
Is the first break-even month permanent?
Not necessarily. A later crossing into a disadvantage is shown separately. Inspect the timeline at the month relevant to you.