VIN Structure Breakdown
Decoding the 17-Character VIN Format
Since 1981, all vehicles manufactured for use in the United States have been required to have a standardized 17-character Vehicle Identification Number (VIN). This standardization was established by the National Highway Traffic Safety Administration (NHTSA) to create a uniform system for identifying vehicles.
The modern VIN is divided into three main sections, each containing specific information about the vehicle. Understanding these sections can help you extract valuable details about any vehicle's origin, features, and production information.
Section 1: World Manufacturer Identifier (WMI)
Positions 1-3
The first three characters of the VIN form the World Manufacturer Identifier (WMI), which provides information about the vehicle's country of origin and manufacturer.
- 1st Character: Identifies the country or region of manufacture
- 2nd Character: Identifies the manufacturer
- 3rd Character: Specifies the vehicle type or manufacturing division
Common Region Codes (1st digit)
- 1-5: North America
- J-R: Asia
- S-Z: Europe
- 6-7: Oceania
- 8-9: South America
Examples
- 1G1: General Motors (US)
- JHM: Honda (Japan)
- WVW: Volkswagen (Germany)
- 3FA: Ford (Mexico)
Section 2: Vehicle Descriptor Section (VDS)
Positions 4-9
The six characters in positions 4 through 9 make up the Vehicle Descriptor Section (VDS). This section describes the vehicle's attributes and includes a mandatory check digit for verification.
- Positions 4-8: Describe vehicle features such as model, body style, engine type, etc. (coding varies by manufacturer)
- Position 9: Check digit used for VIN validation
Check Digit Calculation
The check digit is calculated using a complex algorithm that assigns values to each character in the VIN and uses a weighted multiplication system.
This digit helps detect errors in VIN transcription and is essential for VIN validation. If performing a calculation on a valid VIN doesn't result in the listed check digit, the VIN may be incorrect.
Section 3: Vehicle Identifier Section (VIS)
Positions 10-17
The final eight characters make up the Vehicle Identifier Section (VIS), which includes unique production information that distinguishes one vehicle from another with identical specifications.
- Position 10: Model year code
- Position 11: Assembly plant code
- Positions 12-17: Production sequence number
Model Year Codes (10th digit)
Note: I, O, Q, U, Z are not used due to similarity with numbers.
Special VIN Rules and Restrictions
- The letters I, O, and Q are never used in VINs to avoid confusion with the numbers 1 and 0
- U, Z, and the number 0 are never used in the 10th position (year code)
- No two vehicles manufactured for sale in North America can have the same VIN within a 30-year period
- The VIN is typically displayed on a metal plate attached to the dashboard near the windshield on the driver's side
- VINs are also usually stamped on other parts of the vehicle, such as the driver's door or engine block
Why Understanding VIN Structure Matters
Knowing how to decode a VIN can be incredibly valuable for:
For Vehicle Owners
- Verifying vehicle specifications when purchasing parts
- Confirming vehicle history reports are for the correct vehicle
- Checking if your vehicle is subject to recalls
- Properly registering and insuring your vehicle
For Professionals
- Auto technicians can verify correct parts compatibility
- Insurance adjusters can confirm vehicle details
- Law enforcement can identify stolen vehicles
- DMV officials can properly register vehicles