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Diminished value from a Kelley Blue Book figure
A guide value answers what a car like yours is worth. Diminished value is about what yours is worth now that its record shows an accident. Here is how the first number feeds the second.
There is no Kelley Blue Book diminished value figure to look up, because a guide value describes a model, year, trim and mileage rather than the record attached to your VIN. What it gives you is the pre-accident value — the one input the insurer's formula starts from.
Put that figure in below with your mileage and the damage severity, and the calculator runs the insurer's formula on it, step by step. Nothing is submitted or stored.
What the formula produces
Enter a value and an odometer reading to see the number.
The formula never looks at your car's market.
It ignores what comparable vehicles with an accident on record actually list for, what was replaced versus repaired, and any written offer you already hold. Our free estimate uses those, and shows you both numbers side by side.
Calculate My Value LossFree, about 2 minutes, no account.
Which guide figure to use
Use the one that matches how you would have sold the car. A private-party figure is the closest thing to what an owner would have got from a buyer; a trade-in figure is what a dealer would have paid, and it is lower. Whichever you use, use the same basis on both sides of any comparison you make later.
Get it for the exact trim, the mileage on the day of the accident and your own market, print it with the date on it, and keep that print. A dated figure you can produce beats a remembered one every time.
Where a guide value stops
A guide value is built from a large pool of transactions, which is what makes it a good average and a poor description of one car. It cannot see that your metro is short of your model this month, and it cannot see the accident entry a buyer will pull up before making an offer.
That second limit is the whole subject. A car with a clean record and the same car with a repaired accident on record are two different products in a buyer's hands, and no guide value distinguishes them.
What replaces it in a real estimate
Listings for your year, trim and mileage: the clean ones and the ones carrying an accident record, in your market, at the same moment. The gap between those two sets is the loss, and it is measurable in a way that a formula applied to a guide value is not.
Our estimate is built that way, and our method is published with its coefficients so the figure can be checked rather than believed.
Questions
Is there a KBB diminished value calculator?
There is no Kelley Blue Book diminished value figure to look up. A guide value answers what a car like yours is worth, not what yours is worth with an accident on its record. The calculator on this page runs the insurer's 17c formula on a guide value, which is how the two numbers connect.
Which Kelley Blue Book value should I use as the pre-accident value?
The basis that matches how you would have sold the car — private party for an owner-to-buyer sale, trade-in for a dealer. Pull it for the exact trim and for the mileage on the day of the accident, and keep a dated print-out.
Do insurers use guide values for diminished value?
The common 17c calculation starts from a guide value and takes ten percent of it before applying a damage multiplier and a mileage multiplier. So the starting figure is often one you can look up yourself, which is what makes the rest of the arithmetic checkable.
Why is the figure this calculator returns so small?
Because the formula caps at ten percent of the pre-accident value before either multiplier is applied, and both multipliers can only reduce it. The mileage multiplier reaches 0.00 at 100,000 miles, which zeroes the result outright. That is the arithmetic, not a measurement of your car.
Does a guide value count as evidence?
As evidence of the pre-accident value, a dated print-out for your exact trim and mileage is reasonable and widely used. As evidence of the loss it is not, because the figure does not know about the accident record at all.
Read next
- Guide values in full — What they are good for, and where they stop.
- The formula itself — Both multiplier tables, with the source.
- Our method — What we use instead of a book figure.
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