Diminished value calculator
Find out what your car lost in resale value after a not-at-fault accident, and how much more that is than the number the insurer will open with. About three minutes.
- No account needed
- Estimate is free
- Method published in full
- 30-day refund, no questions
What it measures
What actually moves a diminished value figure
Free calculators tend to take a flat percentage of repair cost. That is not how the used market prices an accident, and it is the first thing a competent adjuster will point out.
Repair cost against the car’s value
The strongest single signal, and the same one a buyer reads off the history report. A $9,000 repair on a $30,000 car is a fundamentally different claim from a $1,500 one.
Structural or frame repair
The most heavily discounted item on any vehicle history report. Buyers and inspectors treat unibody work as permanent, whatever the shop achieved.
Age and mileage against expectation
A near-new, low-mileage car has the furthest to fall, its buyers are paying a premium for as-new condition and have plenty of clean alternatives.
Market segment
Premium and enthusiast buyers screen harder on history than buyers shopping high-supply economy models on price.
Parts and repair quality
Aftermarket or salvage parts, and any visible imperfection in the finished work, get discounted on top of the accident record itself.
Whether the accident is visible
Diminished value depends on buyers being able to see the accident. Until it appears on Carfax or AutoCheck, an adjuster has a real argument that no market discount exists yet.
Every coefficient behind these factors is published on our methodology page, including the curve shape and the caps. We would rather you check our work than take it on trust, and so would the adjuster reading your report.
How to calculate diminished value yourself
If you would rather do the arithmetic by hand, the shape of the calculation is straightforward. Start with what the car was worth the day before the accident, a private-party or retail figure from Kelley Blue Book, J.D. Power or Edmunds for your exact year, trim and mileage. Then work out what the same vehicle sells for now that its history report shows a reported accident. The gap is your diminished value.
The hard part is the second number, which is why most people either guess it or accept whatever the insurer says. The practical way to find it is comparable listings: pull four to six listings of the same year, make, model and trim, some with clean histories, some with reported accidents, adjust each for the mileage difference against your car, and read the spread. That is exactly what this calculator does when you supply the listings, and what the valuation report prints as your supporting exhibit.
What you should notdo is apply the insurer's 17c formula to your own claim. It caps the loss at 10% of the vehicle's value before any other reduction, then multiplies it down for damage and again for mileage, reaching exactly zero for any car with over 100,000 miles. We break the formula down in full here, including why the mileage multiplier is double-counting.
Is a free calculator enough to get paid?
No, and this is worth being direct about. A number on a website is not evidence. Adjusters settle diminished value claims against documentation: a written valuation that shows its method, comparable listings that support the figure, a rebuttal of the formula they opened with, and a demand letter that cites the legal basis in your state and sets a response deadline.
That packet is what we sell, for $200–$400 less than an appraiser charges. The estimate above is free whether or not you buy it, and if your claim turns out to be too small to be worth pursuing, the calculator will tell you that instead of taking your money.
Rules differ by state
Filing deadlines range from 2 to 10 years, shared-fault rules vary sharply, and Michigan, Nebraska, North Dakota do not permit the standard claim at all. The calculator applies your state automatically. These pages explain it.
Calculator FAQ
About this calculator
How accurate is this diminished value calculator?
The calculator uses a documented method built from the factors that actually move resale price: repair cost relative to vehicle value, structural damage, airbag deployment, age, mileage against expectation, market segment, parts used and repair quality. The method and every coefficient are published on our methodology page. Accuracy rises sharply when you supply a sourced pre-loss value and comparable listings, and the tool tells you where your inputs are weak rather than presenting a false precision.
What information do I need to use it?
Your vehicle’s year, make, model and mileage; the date and state of the accident; how severe the damage was; the repair cost; and your car’s market value before the accident. The repair cost is on the shop’s invoice or the insurer’s estimate. The pre-loss value takes two minutes to look up on Kelley Blue Book or Edmunds.
Is the calculator really free?
Yes, and it does not ask for an email to show you the number. The estimate, the range, the factor breakdown and the comparison against the insurer’s 17c formula are all free. You only pay if you want the valuation report and demand letter to send to the insurer.
Why is your number higher than my insurer’s offer?
Because the two are measuring different things. The insurer’s 17c formula caps the loss at 10% of the car’s value and then multiplies it down for damage and mileage. Our method estimates what the market actually discounts an accident-branded example of your vehicle by. The gap between the two is the reason this product exists, and the report explains it line by line so you can put it in front of an adjuster.
Ready to turn the number into a claim?
Add your details and we generate the valuation report and demand letter, tailored to your car and your state.