VIN Check Digit Validator

About this calculator

Every 17-character Vehicle Identification Number encodes a self-check: this calculator applies the same method automakers use — assigning each letter a numeric value (A=1, B=2, C=3... J=1, K=2... skipping I, O, Q), multiplying by a fixed weight for its position (8-7-6-5-4-3-2-10-0-9-8-7-6-5-4-3-2, where position 9 itself carries weight 0), summing the 17 products, and taking the remainder after dividing by 11. A remainder of 10 becomes the letter X, and the result must match the actual 9th character.

The check digit was mandated by the U.S. Department of Transportation (per SAE J853 and 49 CFR 565) so a single mistyped or transposed character can be caught instantly, and it's used by dealers, DMV clerks, insurance underwriters and used-car buyers to confirm a VIN hasn't been miskeyed or altered before they trust the rest of a vehicle's history to it.