Used-Car Offer Calculator
Enter the seller’s asking price and your own researched fair value or range. This free worksheet converts those assumptions into an opening range and ceiling. It does not independently value the car.
Calculations stay in this page. No account, email or payment required. Enter USD amounts without commas, up to $1,000,000 per field. A blank repair allowance counts as zero. Leave fair high blank to use a single fair value.
Formula and assumptions
Subtract the repair allowance once from both ends of your fair range. The opening range runs from the adjusted low to the adjusted midpoint, with the midpoint rounded down to cents. The ceiling is the adjusted high. Cap every output at the asking price. A single fair value produces a single opening figure. If repairs consume the fair low, no offer is suggested: reassess the car and the estimate.
Worked example
Fictional example: an asking price of $20,000, your fair range of $18,000–$19,000 and $500 of repairs produce an opening range of $17,500–$18,000 and an $18,500 ceiling. These figures follow the chosen planning rule; they are not a prediction of seller acceptance or an independent appraisal.
What the result cannot tell you
Enter only repairs not already reflected in your fair range. These are vehicle prices before taxes and purchase charges, not an affordability assessment. Your own budget may require a lower ceiling. The tool checks no history, title, recalls or physical condition and cannot decide whether this car is safe or appropriate to buy. Unresolved problems need evidence, not an arbitrary discount.
WorthTheCar: Evidence and analyst review — source checked September 14, 2026.