Diminished Value Calculator

Why diminished value matters

A repaired car is worth less than an unrepaired car of the same year, mileage, and trim. Buyers see the accident history on CARFAX, dealers offer less on trade-in, and the vehicle's resale market shrinks. That gap, between what your car was worth before the accident and what it's worth now after a documented repair, is your diminished value.

For most cars in New York, diminished value runs between 3 percent and 8 percent of the pre-accident value. On a $20,000 vehicle, that's $600 to $1,600 left on the table if you don't file. On a higher-value or lower-mileage car, it can easily exceed $5,000.

How the 17c formula works

The 17c formula came out of a 2001 Georgia case and is now the most common starting point insurers use across the country. It has four steps:

• Base loss. 10 percent of the pre-accident market value. This is the formula's rough cap on diminished value.
• Damage multiplier. 0.00 (no structural damage) to 1.00 (severe, multiple panels, frame work). Most everyday accidents land at 0.25 or 0.50.
• Mileage multiplier. 1.00 below 20,000 miles, dropping by 0.20 for each 20,000-mile bracket, hitting 0.00 past 100,000 miles. The formula assumes high-mileage cars already have depreciation baked in.
• Prior-accident reduction. Most insurers cut the result in half when there is a documented prior accident. Some deny entirely.

Use this with the rest of the toolkit

• Build a damage report first with the vehicle damage checklist so the severity tier you pick matches what your shop actually wrote.
• Run the insurance claim readiness checker to make sure you have every document before you submit a DV demand.
• Estimate the underlying repair cost with the car repair cost estimator if you're still negotiating the repair side of the claim.

Common reasons claims get denied (and how to counter)

• “Your repair was perfect, no DV applies.” Counter: inherent DV applies regardless of repair quality because CARFAX history alone reduces resale value.
• “Mileage is too high.” Counter applies only past 100,000 miles. Below that, the 17c formula still produces a defensible number.
• “You don't have an appraisal.” Counter: an independent appraisal ($200 to $500) typically raises the offer by far more than its cost.
• “The 17c formula isn't binding.” Correct, it isn't. Cite comparable resale data from your zip code as the alternative anchor.

For a deeper read

Our blog post Diminished value claims in New York: how much is your claim really worth walks through a full 2021 Honda Accord example end to end, plus the documents and the demand-letter structure that get insurers to settle.