A free car appraisal in 30 seconds, no email required
Kelley Blue Book and Edmunds make you click through ads, enter your email, and pick from limited dropdowns. This calculator is faster: class, age, mileage, condition, accident yes/no, done. The output is three numbers spanning trade-in to retail.
For day-to-day decisions (whether to trade in, what to ask in a private sale, whether a dealer offer is fair), this calculator is usually enough. For specific high-stakes transactions, also cross-check with KBB or Edmunds.
The three numbers explained
- Trade-in value: What a dealer offers when you bring the car in to buy a new one. The lowest of the three because the dealer needs profit on the resale.
- Private party value: What an individual buyer pays cash, no warranty involved. The fair market value.
- Retail value: What you would pay buying from a dealer's used-car lot. Includes dealer prep, warranty, and margin. The highest of the three.
The spread between trade-in and retail is roughly 35 percent. That spread is dealer working margin. Selling privately captures most of it for yourself; trading in surrenders it for convenience.
How the calculation works
Four adjustments to the original MSRP:
- Age depreciation using a class-based curve. Year 1 loses about 20 percent, year 2 cumulative 33%, year 5 about 56% for mid-range vehicles. Luxury depreciates faster (65% at year 5), trucks slower (45%).
- Mileage adjustment based on actual versus expected (12,000 miles per year). Each 10,000 miles over expected reduces value 3 percent; under expected adds 3 percent.
- Condition multiplier: excellent (1.0), good (0.88), fair (0.72), poor (0.55). Big difference between excellent and good if you can document it.
- Accident penalty: 17.5 percent reduction (midpoint of 10 to 25 percent industry range) if there is any reported accident on the Carfax record.
Trade-in or private sale
The single most common question this calculator answers. The math:
- Trade-in is 25 to 30 percent less than private party. On a $20,000 private value, that's $5,000 to $6,000 less.
- Time investment for private sale is 2 to 8 weeks of listings, showings, negotiations, and paperwork. Trade-in happens in one afternoon.
- Tax savings on trade-in: in most states, you only pay sales tax on the difference between new car price and trade-in value. On a $30,000 new car with $15,000 trade-in at 7 percent tax, that's $1,050 saved.
- Risk of private sale: buyer ghosts after inspection, payment doesn't clear, or buyer claims problems after sale.
Rule of thumb: if the gap between trade-in and private party is under $3,000, trade in. Over $3,000 and the private sale work is worth it.
If your car has an accident on Carfax
The 10 to 25 percent accident discount is real and unavoidable at sale time. But if the accident was not your fault, that value loss is recoverable as a diminished value claim against the at-fault driver's insurer.
Most drivers never file because they don't know it exists. Run the diminished value calculator to estimate the recoverable amount, then follow our demand letter template to file. Typical recovery: $1,500 to $5,000.
Pair with our other tools: Before any used car transaction, run the VIN decoder to verify the vehicle spec. If considering a new purchase, check the true cost to own calculator for the full 5-year picture, and the dealer markup calculator for fair pricing.