How we calculate your diminished value

The short version

We start from your car's pre-accident value, then estimate how much the resale market discounts a car like yours once it has this accident on its history. The worse the damage and the newer the car, the more value it loses. The result is a market-based estimate of your loss — shown next to what the insurer's “17c” formula would offer, so you can see the gap.

How the estimate is built

Each input you enter adjusts the number in a specific direction. Here is what each one does.

Pre-accident value (PAV)

The starting point — your car's market value the day before the crash, from KBB or Edmunds. Every other factor adjusts this number, so the estimate is always a share of your car's value, not a flat figure.

Damage severity

The single biggest driver. Severity sets the base loss rate before any other adjustment — structural or major damage causes far more resale loss than cosmetic. The starting rates we use, as a percentage of your car's pre-accident value:

Severity	Base rate	Won't exceed
Minor	6%	10%
Moderate	13%	20%
Severe	25%	35%

Structural / frame damage & airbag deployment

These show up on history reports and scare buyers most, so each one pushes the estimate up.

Mileage & model year

Newer, lower-mileage cars have more value to lose, so they diminish more in dollar terms and push the estimate up. Older, high-mileage cars have less to lose, so the estimate comes down.

Prior accidents & title status

A prior accident on the same car pushes the estimate down — there's less “clean-history premium” left to lose. A branded (salvage/rebuilt) title is a different situation entirely: rather than fold it into the number, we flag it, because branded-title cars aren't on the standard diminished-value path and need a different approach.

Repair cost (optional)

When you provide it, we use the repair cost relative to your car's value as a cross-check on severity — a repair that costs a large share of the car's value nudges the estimate up.

After applying those factors, we cap the result at the ceiling for that severity (the “won't exceed” column above), so no single factor can push the number somewhere we couldn't defend. A small floor of 3%backstops the low end — but we don't prop up genuinely low-value cases either, so a very old, high-mileage car with only cosmetic damage settles at its real, low rate rather than being over-estimated. We then show a band of about ±10% around the figure, because an honest estimate should be upfront about uncertainty.

Why our number and the insurer's number differ

Many insurers estimate diminished value using a formula often called “17c.” It starts by capping your loss at 10%of your car's value, then reduces that further using a fixed damage rating and a mileage table. Because it begins from an arbitrary cap rather than from real resale data, it tends to produce a low number. Our estimate isn't bound by that 10%cap — it works from how the market actually prices accident history. That's why the two figures can differ substantially, and why we show them side by side.

What this estimate is — and isn't

• It is a market-based starting point for what you can reasonably argue you're owed.
• It is not a certified appraisal, a guarantee of what you'll recover, or legal advice.
• Your actual recovery depends on your state's rules, the evidence you present, and how persistently you pursue the claim.
• For a claim headed to dispute or court, an independent appraisal carries more weight than any online estimate — including this one.

What this is based on

Think of this as a screening tool, not a valuation. The base rates above are anchored to inherent-diminished-value market data — vehicle-history reporting and certified-appraiser experience generally put inherent DV in the range of roughly 10–25% of value depending on severity, and our conservative starting rates sit inside that range. The model then scales that figure by the factors a real buyer cares about.

The number that actually holds up in a dispute isn't this estimate — it's market comparables: real sales and listings of vehicles like yours, with and without an accident on record. That side-by-side price difference is the hard evidence an insurer or a small-claims judge responds to, and documenting it is exactly what the claim kit is built to help you do.

We publish these figures in the open so you can judge the reasoning for yourself. They are defensible starting numbers, not a certified or legal valuation of your specific car.