Car Refinance Calculator
Compare your current auto loan with a proposed refinance using payments, interest, fees, remaining balances and a true break-even estimate.
Refinance comparison
| Option | Payments made | Remaining balance | Payments + balance + upfront costs |
|---|---|---|---|
| Keep current loan | — | — | — |
| Refinance | — | — | — |
How the refinance comparison works
The calculator creates two monthly amortization schedules from today: one for keeping the current auto loan and one for the proposed refinance. It includes refinance fees, any prepayment penalty and optional extra principal.
- Monthly payment = P × r(1 + r)n ÷ [(1 + r)n − 1].
- New amount financed = current payoff balance + financed refinance fees.
- Lifetime refinance cost above the current balance = new payments + upfront fees + penalty − current payoff balance.
- Lifetime savings = remaining current-loan interest − lifetime refinance cost above the current balance.
At 0% APR, the scheduled payment is principal divided by the number of months. Extra principal shortens the modeled refinance term and reduces its interest.
Why a lower payment is not always savings
A longer new term may reduce the monthly payment while increasing total interest. For that reason, the break-even test compares cumulative payments plus the remaining loan balance and upfront costs—not only the difference between the two monthly payments.
Checked example
For a $22,000 payoff balance at 8.5% with 48 months remaining, refinancing to 6.25% for 48 months with $400 paid upfront lowers both the payment and total modeled financing cost. Change the new term to 60 or 72 months to see why the payment can fall even when the long-run result becomes less attractive.
How to use this calculator
- Obtain the current payoff balance, APR, remaining term and any prepayment penalty.
- Enter the quoted refinance APR, term and all lender or title fees.
- Select whether fees are paid upfront or included in the new principal.
- Choose how many months you expect to keep the refinanced loan or vehicle.
- Compare lifetime savings, break-even and the remaining balances—not just monthly payments.
Important limitations
This is an educational estimate, not a loan offer or approval. It assumes fixed APRs, monthly payments and no late payments. It does not determine credit eligibility, vehicle-value limits, loan-to-value rules, taxes, insurance, title requirements, gap coverage, warranty cancellation, daily-interest payoff adjustments or lender-specific rounding. A payoff quote may change each day. Verify the contract, fees and funding date with both lenders.
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