📋 Overview
Every car built after 1981 has a 17-character VIN. Each character encodes specific information. Decoding it tells you the country of origin, manufacturer, engine, model year, assembly plant, and serial number. The federal NHTSA database is the authoritative source.
📝 Step-by-Step Checklist
- Find the VIN in two placesBottom-left corner of the windshield (visible from outside) and the driver-side door jamb sticker. They MUST match. If they don't, walk away - that is a clone or stolen car.
- Confirm 17 charactersPre-1981 VINs are shorter. Modern VINs are exactly 17 characters with no I, O, or Q (to avoid confusion with 1 and 0).
- Decode position 1 - Country1, 4, 5 = USA. 2 = Canada. 3 = Mexico. J = Japan. K = South Korea. W = Germany. S = UK. Y = Sweden/Finland.
- Decode positions 2–3 - ManufacturerCombined with position 1, this is the World Manufacturer Identifier (WMI). 1FT = Ford Truck. 1G1 = Chevrolet. JTD = Toyota. KMH = Hyundai.
- Decode positions 4–8 - Vehicle attributesEncodes model, body style, engine, restraint system. Each manufacturer uses its own pattern.
- Decode position 9 - Check digitA math checksum that validates the VIN. If it fails, the VIN may be fraudulent.
- Decode position 10 - Model yearA = 1980 or 2010, B = 1981/2011, … Y = 2000, 1 = 2001, … 9 = 2009, A again = 2010. Combine with build date to disambiguate.
- Decode position 11 - Assembly plantEach manufacturer assigns its own codes.
- Decode positions 12–17 - Serial numberSequential production number for that year and plant.
- Use the free NHTSA decoderGo to vpic.nhtsa.dot.gov/decoder or use our /vin tool. NHTSA is the federal authority and returns build specs plus open recalls free.
🔗 Related Guides
❓ Frequently Asked Questions
Where can I decode a VIN for free?
NHTSA at vpic.nhtsa.dot.gov/decoder is the federal free tool. AmpAuto's /vin page wraps the same data with recalls and history.
Why are I, O, and Q not used in VINs?
They look too much like 1 and 0. The ISO 3779 standard excludes them to prevent transcription errors.
What does the 10th digit of a VIN mean?
Model year. The cycle repeats every 30 years (A=1980 and A=2010), so combine with build month and other info to disambiguate.
Can two cars have the same VIN?
No, by federal law each VIN must be unique. If you see two cars with the same VIN, one is a clone - report to NICB at 1-800-TEL-NICB.
How do I know if a VIN is fake?
The 9th digit (check digit) must match a calculated checksum. If a NHTSA decoder returns no results or an error, the VIN may be invalid.
What is the difference between a VIN and a license plate?
VIN is permanent and tied to the car for life. License plates are tied to the owner and state and change with each sale or move.