VIN (Vehicle Identification Number)

What It Means

The Vehicle Identification Number (VIN) is a standardized 17-character alphanumeric code uniquely assigned to every motor vehicle manufactured worldwide since 1981, defined by ISO 3779 and, in the U.S., by 49 CFR Part 565. Before 1981, VINs varied widely in length and format; the 17-character standard was adopted to eliminate ambiguity across international markets. Each of the 17 positions encodes specific information. Positions 1 through 3 form the World Manufacturer Identifier (WMI), assigned by SAE International, for example, "1FT" identifies a Ford truck built in the U.S., "WBA" identifies a BMW passenger car. Positions 4 through 8 form the Vehicle Descriptor Section (VDS), encoding model, body style, engine type, restraint system, and series. Position 9 is a check digit calculated from a weighted sum of the other 16 characters and is used to validate VIN authenticity. Position 10 encodes the model year using a rolling alphabet (2026 = V, 2027 = W, skipping I, O, Q, U, Z, and 0). Position 11 encodes the assembly plant. Positions 12 through 17 form the Vehicle Identifier Section (VIS), a sequential production number unique within that plant and model year. VINs are physically stamped or laser-etched on multiple locations on every vehicle, the driver-side dashboard (visible through the windshield), the driver-side door jamb, the engine block, and the frame or chassis, to make VIN tampering detectable. NHTSA's free VIN lookup at nhtsa.gov/recalls returns all open and closed recalls for a specific vehicle, and the NHTSA vPIC (Product Information Catalog) API decodes the VIN into structured vehicle information. RecallCheck uses the NHTSA vPIC API to decode VINs and keys all recall and complaint lookups to make/model/year combinations derived from the VIN decode.

VIN (Vehicle Identification Number) is one of the NHTSA or vehicle-safety concepts that recurs across RecallIndex. The definition above is the technical answer; below is how the concept connects to the NHTSA data that drives every vehicle page on the site.

In the RecallIndex Safety Score, this concept feeds one of the four factor weights — recall severity (40 percent), complaint frequency (30 percent), crash and fire reports (20 percent), or trend direction (10 percent). The methodology page on the site walks through every input in detail.

Frequently Asked Questions