Car Loan Refinance Calculator: New Payment and Interest Saved
A car loan refinance calculator compares the remaining cost of an existing auto loan with a proposed replacement loan. It shows payment change, projected interest, and how long fee savings may take to recover.
Quick answer
Refinancing can reduce the payment because of a lower rate, a longer term, or both. A lower payment is not always a lower total cost, so compare interest and fees as well as monthly savings.
At a glance
- What it calculates
- Compare an existing auto loan with a refinance offer, including payment savings, total interest, and break-even time.
- Who it is for
- US car owners with improved credit or falling rates considering an auto refinance.
- Coverage
- United States (federal rules; state and local rules vary)
- Data and assumptions
- A fixed-rate replacement loan starting at the current payoff balance, with fees entered separately; GAP, warranty and negative-equity rollovers are excluded.
- Cost
- Free, no signup, calculations run in your browser
- Last reviewed
- 2026-07-09
Calculator
How to use this calculator
- Enter the current payoff balance, APR, and months remaining.
- Enter the proposed rate, term, and fees.
- Compare payment savings and total savings.
- Check for prepayment charges and confirm the payoff quote.
Explanation
What it is
A car loan refinance calculator compares the remaining cost of an existing auto loan with a proposed replacement loan. It shows payment change, projected interest, and how long fee savings may take to recover.
How it works
The calculator amortizes the current payoff balance under both the current remaining schedule and the proposed refinance. It adds entered fees to the new principal and compares total scheduled payments.
When to use it
Use it when your credit score has improved, rates have fallen, or you are more than a few months into a loan taken at a dealer rate.
Limitations
- Lender loan-to-value, vehicle age and mileage limits are not checked here.
- Title, registration and lien fees vary by state and are excluded.
- Rate offers depend on credit profile, vehicle and lender policy.
Key terms
- Payoff balance
- The amount needed to satisfy the existing loan on a given date.
- Refinance
- Replacing an existing loan with a new loan.
- Break-even period
- Time for monthly savings to recover upfront fees.
- Term extension
- Repaying over more months, which may lower payment but increase interest.
Formula
The calculator amortizes the current payoff balance under both the current remaining schedule and the proposed refinance. It adds entered fees to the new principal and compares total scheduled payments.
Worked example
Refinancing a $25,000 balance from 9% to 6.5% for the same 48 months can lower payment and interest, but a longer replacement term could lower payment while increasing total cost.
FAQ
Is refinancing a car loan worth it?
It may be worthwhile when rate and total-cost savings exceed fees and you expect to keep the loan long enough to benefit.
Will refinancing lower my car payment?
It can if the rate is lower or the term is longer. Verify whether the total remaining cost also falls.
Can I refinance an upside-down car loan?
Possibly, but lenders may limit loan-to-value ratios or require cash to reduce the balance.
Does refinancing restart the loan term?
The new loan has its own term. Choosing more months than remain on the current loan may increase total interest.
What credit score is needed to refinance?
Requirements vary by lender, vehicle, income, loan-to-value ratio, and credit profile. Compare actual prequalified offers where available.
Common mistakes
- Extending the term so the payment falls while total interest rises.
- Refinancing when the vehicle is worth less than the balance owed.
- Overlooking GAP or warranty products that do not transfer to the new loan.
- Applying with many lenders over a long window instead of one short shopping period.
Tips
- Refinance the payoff balance, not the original loan amount.
- Keep the remaining term the same to capture rate savings instead of resetting it.
- Check for prepayment terms and title transfer fees before applying.
- Compare credit unions, which frequently price auto refinance below banks.
Sources and editorial review
Educational estimates only; not personalized financial, tax, legal, lending, investment, or insurance advice.