Auto refinance calculator.

How to read the result

The calculator runs the math on both loans using a standard amortization formula. Two numbers matter most:

• Monthly savings: what you keep in your pocket each month after refinancing. Useful if cash flow is the goal.
• Net savings after fee: total dollars saved over the new loan's life, minus any origination fee. This is the real economic answer to "is the refi worth it?"

If net savings is positive, the refi pencils. If it's negative, you'd lose money on the refinance even though the monthly might look attractive.

Watch for term extension

The classic refi mistake is extending the term to lower the monthly payment. The lower monthly looks like savings, but you may be paying more in total interest because the loan runs longer. To see this clearly, set the new term to your current months remaining — that gives you a true rate-only comparison.

What the calculator doesn't include

It doesn't account for state title-transfer fees (typically $20–$100), GAP insurance changes, or any prepayment penalty on your current loan. Those are typically small relative to the savings, but check your contract before refinancing.

Frequently asked

Is a 1-point APR drop enough to refinance?

If you have 24+ months remaining and there's no origination fee, yes. Below that, the friction of switching lenders typically isn't worth it.

What if my new offer has a longer term than I want?

Pick the shorter term — most lenders let you choose. The calculator shows both monthly and lifetime numbers so you can compare.

Will refinancing affect my credit score?

The hard pull costs 5–10 FICO points temporarily. Recovers within 12 months. If you're applying for a mortgage in the next 6 months, hold off on the auto refi.

Read the full guide on when refinancing actually makes sense →