Diminished Value Calculator (17c)
Estimate what your car lost in resale value after a not-at-fault accident. This tool runs the 17c formula insurers commonly use, then shows you the real market-value method that often produces a higher, fairer number.
Estimate only. This is based on the 17c formula insurers commonly use. Your actual recoverable amount may be higher or lower and is not guaranteed. It depends on fault, your state's rules, the policy, and your evidence.
Why the 17c number is usually too low
17c was popularized by insurers to limit what they pay. It caps your loss at 10% of the car's value and then multiplies it down for damage and mileage. It is a starting point for the insurer, not a fair measure of your real loss.
The honest way to measure diminished value is the market-value method: compare what your exact car would sell for with a clean history versus with a reported accident on its record.
The market-value method (often higher)
Pull three to five real listings for your year, make, model, trim, and mileage with a clean history, and three to five comparable cars with a reported accident. The difference in average asking price is a defensible, real-world estimate of your diminished value — and it is frequently larger than the 17c figure.
What to do with your estimate
- Run both numbers before you speak to the adjuster, so you know their opening offer is a floor, not a ceiling.
- Put your claim in writing. Use our diminished value demand letter template.
- Follow the step-by-step in how to file a diminished value claim.
- Check whether your state even allows the claim on our when you may need a lawyer page and your state guide.
This is general information, not legal advice — consult a licensed attorney in your state. Diminished value rules and deadlines vary by state and can change; verify with your state Department of Insurance.