Negative Equity Car Calculator – Upside-Down Car Loan Costs

Cars lose value fastest in their first few years, often faster than a long loan is paid down. That leaves many drivers upside down: owing more than the car is worth. This calculator shows how much negative equity you have, what happens to your payment if you roll it into your next car loan, and what that shortfall really costs once interest is added.

How to use the negative equity car calculator

Enter your current car’s payoff amount. Ask your lender for an exact quote.
Enter its trade-in value. Get offers from dealers or online buyers.
Enter the price of the next car, including tax and fees.
Enter your cash down payment, the new loan’s interest rate and the term.

The results show your negative equity, the new loan amount with it rolled in, the new monthly payment, the cost of rolling it over with interest, and the new loan’s loan-to-value ratio.

How negative equity is calculated

negative equity = payoff amount − trade-in value
new loan = next car's price − down payment + negative equity
cost of rolling over = payment on the negative equity alone × number of months

Worked example

You owe $22,000 on a car worth $17,000 as a trade-in. The next car costs $36,000 with tax and fees, and you have $2,000 to put down. The new loan is at 7% for 72 months.

Negative equity: 22,000 − 17,000 = $5,000.
New loan: 36,000 − 2,000 + 5,000 = $39,000.
Payment: $664.91 a month, compared with $579.67 without the rollover.
The $5,000 shortfall costs $6,137.64 over 72 months, $1,137.64 of it interest.
Loan-to-value: 39,000 ÷ 36,000 = 108%. You start the new loan upside down too.

How to avoid rolling negative equity

Keep your current car longer and pay extra toward principal until you’re right side up. The auto loan payoff calculator shows how fast extra payments close the gap.
Pay the difference in cash if you can, instead of financing it at interest.
Sell privately. A private sale often brings more than a trade-in offer.
Choose a cheaper next car and a shorter term, so the new loan doesn’t stay underwater.
Look for rebates on the next car. A manufacturer rebate applied to the price can offset part of the negative equity, though it is better used to pay it off than to hide it in the loan.

Common mistakes

Focusing on the monthly payment. Dealers can hide negative equity by stretching the term.
Using the statement balance. Use the exact payoff amount, which includes interest since your last payment.
Stacking rollovers. Each time negative equity is rolled into the next loan, the hole gets deeper.
Skipping GAP coverage on a loan above the car’s value. If the car is totaled, you could owe thousands with no car.

To check the payment on a new car without a rollover, use the car loan calculator. To set a sensible budget first, use the car affordability calculator.

Frequently asked questions

What is negative equity on a car?

It means you owe more on the car loan than the car is worth. If your payoff is $22,000 and the car's trade-in value is $17,000, you have $5,000 of negative equity, also called being "upside down" or "underwater".

What happens to negative equity when I trade in?

You either pay the difference in cash, or the dealer adds it to your new loan. Rolling it over means you borrow more than the new car's price and pay interest on your old car's shortfall.

How can I get out of an upside-down car loan?

Keep the car and make extra principal payments until the balance falls below its value, pay the difference in cash when you trade, or sell privately for more than the trade-in offer. Refinancing to a lower rate can help, but lenders may limit loans above the car's value.

Does GAP insurance cover negative equity?

GAP covers the difference between the insurance payout and your loan balance if the car is totaled or stolen. It doesn't pay negative equity when you trade in or sell, and some policies cap or exclude negative equity rolled in from a previous loan.

Last updated November 2, 2026 · By the ZTool team