What is the VIN check digit?
The 9th character of a North American VIN: a digit 0–9 or X calculated from the other 16 characters, used to catch typos and fake VINs.
Each letter is turned into a number (A=1, B=2 … H=8, J=1 … N=5, P=7, R=9, S=2 … Z=9; digits keep their value). Each value is multiplied by its position weight (8, 7, 6, 5, 4, 3, 2, 10, 0, 9, 8, 7, 6, 5, 4, 3, 2) and the products are added. The remainder after dividing by 11 is the check digit, with 10 written as X.
If the 9th character does not match the calculation, the VIN was mistyped or is not genuine. Recall tools validate this before looking anything up.
Worked example
VIN 1M8GDM9AXKP042788. Each character's value times its weight, added up:
| Pos. | Char | Value | Weight | Product |
|---|---|---|---|---|
| 1 | 1 | 1 | 8 | 8 |
| 2 | M | 4 | 7 | 28 |
| 3 | 8 | 8 | 6 | 48 |
| 4 | G | 7 | 5 | 35 |
| 5 | D | 4 | 4 | 16 |
| 6 | M | 4 | 3 | 12 |
| 7 | 9 | 9 | 2 | 18 |
| 8 | A | 1 | 10 | 10 |
| 9 | X | 7 | 0 | 0 |
| 10 | K | 2 | 9 | 18 |
| 11 | P | 7 | 8 | 56 |
| 12 | 0 | 0 | 7 | 0 |
| 13 | 4 | 4 | 6 | 24 |
| 14 | 2 | 2 | 5 | 10 |
| 15 | 7 | 7 | 4 | 28 |
| 16 | 8 | 8 | 3 | 24 |
| 17 | 8 | 8 | 2 | 16 |
Sum = 351. 351 ÷ 11 leaves a remainder of 10, written as X, which matches the 9th character, so the VIN is well formed. (The 9th position itself has weight 0, so it never affects the sum.)
Sources
Related terms
- VIN (Vehicle Identification Number)The 17-character code that identifies one vehicle. Recall lookups use it to tell whether that exact vehicle is in a campaign and whether it has been fixed.
- WMI (World Manufacturer Identifier)The first three characters of a VIN, which identify the manufacturer and the region or country where it is registered.