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VIN basics
What is a VIN?
A vehicle identification number is a 17-character code stamped into every car, truck, motorcycle and trailer built since 1981. It works like a fingerprint: no two vehicles built within 30 years of each other share the same VIN. Manufacturers assign it on the assembly line, governments use it to register and title the vehicle, insurers use it to rate policies, and recall campaigns are tracked against it for the vehicle's entire life.
The format is defined by two international standards, ISO 3779 and ISO 3780, and in the United States by federal regulation 49 CFR Part 565. Those rules are why a VIN can be decoded: each position carries defined meaning rather than being a random serial.
The three sections of a VIN
| Positions | Section | What it encodes |
|---|---|---|
| 1–3 | WMI (World Manufacturer Identifier) | The manufacturer and the country or region where the vehicle was built. 1HG is Honda USA; WBA is BMW Germany. |
| 4–9 | VDS (Vehicle Descriptor Section) | Model, body style, engine, restraint system — each maker defines its own scheme and files it with NHTSA. Position 9 is the check digit. |
| 10–17 | VIS (Vehicle Identifier Section) | Position 10 is the model year code, 11 the assembly plant, and 12–17 the sequential production number. |
Why the letters I, O and Q never appear
The standard bans I, O and Q from every position because they're too easy to confuse with 1 and 0 on a stamped metal plate. If a VIN you've been given contains one of them, it has been transcribed wrong — the culprit is almost always a 1 or a 0.
What a VIN can and can't tell you
Decoding the VIN reveals what the factory built: make, model, year, trim, engine, transmission, drivetrain, plant and factory safety equipment. Combined with government recall records it also reveals open safety recalls. What it cannot reveal is what happened after the car left the factory — accidents, floods, odometer rollbacks and title brands live in separate databases (NMVTIS and commercial services like Carfax and AutoCheck), which is why those reports cost money while decoding is free.
Free build sheet, specs and recall check from official NHTSA data.
Where this data comes from
Our decoder queries vPIC, the Vehicle Product Information Catalog run by the National Highway Traffic Safety Administration. Manufacturers are legally required to submit their VIN coding schemes to NHTSA before selling vehicles in the US, which makes vPIC the authoritative source — the same database most commercial decoders quietly rely on.