Tools

Gap insurance calculator

Chart your loan balance against the car's falling value to see how long you would owe more than it is worth — the window gap insurance covers.

Runs entirely in your browser: nothing you enter is sent or stored by this site. Results are estimates for planning, not a quote or advice.

What it tells you

If your car is totaled or stolen, insurance pays its actual cash value, not what you owe. Early in a loan — especially with a small down payment, a long term or fees rolled into the loan — the balance can be higher than the car's value. gap insurance pays that difference. This calculator estimates how long the gap lasts and how large it gets.

How to use it

  1. Enter the price including any taxes, fees and add-ons you financed.
  2. Enter your down payment plus any trade-in equity.
  3. Enter the APR and loan term.
  4. Adjust the two depreciation assumptions. They are deliberately editable: how fast a car loses value varies a great deal by make, model, mileage and market. A used-car pricing guide can show how your model has held its value.
  5. Tick "used" if the car is not new, so the first-year drop does not apply.

The math

  • The monthly payment uses the standard loan formula; the balance is recalculated each month (interest added, payment subtracted).
  • The car's value falls by the first-year percentage in year one (spread evenly across the months), then by the later-year percentage of the remaining value each year.
  • The gap in any month is loan balance minus estimated value, when positive. The tool reports how many months the loan is underwater and the largest gap.

Reading the result

  • A long underwater window and a large peak gap are the cases where gap coverage earns its price.
  • Gap coverage is sold by many auto insurers as an add-on, by lenders and by dealers; prices can differ widely, so compare. Read the exclusions — many policies cap the payout or exclude your deductible.
  • Leases frequently include gap protection already; check the lease agreement before buying it twice.
  • Once the loan is no longer underwater, gap coverage pays nothing. Cancel it then and ask for any refund of unused premium.

For background, read gap insurance explained. To see an actual settlement, use the total loss payout estimator.

Last reviewed October 4, 2026

Related guides

Gap insurance explained Gap insurance pays the difference between your car's value and what you owe if it's totaled or stolen. Who needs it, where to buy it, what it skips. What happens if your car is totaled and you still owe money How a total-loss payment is split with your lender, what happens when you owe more than the car is worth, and how gap and loan payoff coverage help. Insurance requirements for a financed car Why lenders require collision and comprehensive, how the lienholder is listed, what force-placed insurance costs, and what changes after payoff. Insuring a leased car What leasing companies require (collision, comprehensive, higher liability limits, gap), how the lessor is listed, and what happens in a total loss.

Terms used here

Gap insurance Pays the difference between a totaled car's actual cash value and the larger balance still owed on its loan or lease. Loan/lease payoff coverage Optional coverage that pays part of what you still owe on a financed or leased car if it is totaled or stolen and the payout falls short of the loan. Depreciation The loss in a car's value over time from age, mileage and wear, which insurers account for when calculating actual cash value. Actual cash value What a car was worth just before a loss — replacement cost minus depreciation — and the basis of most total-loss payouts.

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