VIN Number Anatomy: What Every Character Means

Interactive VIN Decoder

Click or hover over any character below to see what it encodes. The VIN is divided into color-coded segments — each with a specific purpose defined by international standards.

VIN Structure Overview

Every Vehicle Identification Number is exactly 17 characters long — no more, no less. This standard was established in 1981 by the International Organization for Standardization (ISO 3779) and is enforced in the United States by NHTSA under Federal Motor Vehicle Safety Standard No. 115.

The 17 characters are divided into three major sections:

• WMI (positions 1–3) — World Manufacturer Identifier
• VDS (positions 4–8) — Vehicle Descriptor Section
• VIS (positions 9–17) — Vehicle Identifier Section

The characters I, O, and Q are never used in VINs because they can be confused with the numbers 1 and 0.

Characters 1–3: World Manufacturer Identifier (WMI)

The first three characters identify where the vehicle was manufactured and by whom. This is assigned by the Society of Automotive Engineers (SAE) in the United States and by the relevant national organization in other countries.

Character 1 — Country of Origin

The first character tells you which country the vehicle was built in. Here are the most common codes:

Character 2 — Manufacturer

The second character identifies the manufacturer. In combination with the first character, it narrows down the exact company. For example, 1G = General Motors (USA), WB = BMW (Germany), JT = Toyota (Japan).

Character 3 — Vehicle Type / Division

The third character, combined with the first two, identifies the vehicle type or manufacturing division. For manufacturers that produce fewer than 1,000 vehicles per year, the third character is always 9, and characters 12–14 provide additional manufacturer identification.

Characters 4–8: Vehicle Descriptor Section (VDS)

These five characters describe the vehicle's key attributes. The specific meaning of each position varies by manufacturer, but they typically encode:

• Body type — sedan, SUV, truck, coupe, etc.
• Engine type — displacement, cylinders, fuel type
• Model — specific model line
• Series / trim — base, sport, luxury, etc.
• Restraint system — airbag configuration and seat belt type

Unlike the WMI and VIS, the VDS is not standardized across manufacturers. Each OEM defines its own encoding scheme for positions 4–8. This is why you need a VIN decoder to interpret these characters — you can't simply look them up in a universal table.

Character 9: Check Digit

Position 9 is a single calculated character used to verify that the VIN has not been transcribed incorrectly. It's the result of a mathematical formula applied to all other 16 characters.

The check digit can be any number 0–9 or the letter X (which represents the value 10). If someone changes even a single character in a VIN, the check digit will no longer validate — making it a simple but effective anti-fraud mechanism.

Character 10: Model Year

A single character encodes the model year. The code cycles every 30 years, so you need to use context (the vehicle's other attributes) to determine whether A means 1980 or 2010.

Note that the letters I, O, Q, U, and Z are skipped, as well as the number 0.

Character 11: Assembly Plant

This character identifies the specific factory where the vehicle was assembled. The code is assigned by each manufacturer and is not standardized across brands. For example, Toyota uses U for their Georgetown, Kentucky plant, while BMW uses A for their Munich, Germany plant.

Characters 12–17: Production Sequence Number

The last six characters are a unique serial number assigned to each vehicle as it rolls off the assembly line. This is what makes every VIN unique — even two identical vehicles built at the same plant on the same day will have different sequence numbers.

For manufacturers producing fewer than 1,000 vehicles per year, positions 12–14 serve as an additional manufacturer identifier, and only positions 15–17 are the sequence number.

How the Check Digit Algorithm Works

The check digit (position 9) is calculated using a weighted modulus-11 algorithm. Here's how it works:

1. Transliterate each letter in the VIN to its numeric value using a fixed mapping (A=1, B=2, C=3, ... H=8, J=1, K=2, ... N=5, P=7, R=9, S=2, T=3, ... Z=9). Numbers keep their own value.
2. Multiply each value by a position weight: [8, 7, 6, 5, 4, 3, 2, 10, 0, 9, 8, 7, 6, 5, 4, 3, 2]
3. Sum all the products together.
4. Divide the sum by 11. The remainder is the check digit. If the remainder is 10, the check digit is X.

If the calculated check digit matches position 9 of the VIN, the VIN is valid. Our free VIN decoder automatically verifies this for every VIN you enter.

A Brief History of VINs

Vehicle identification numbers have been around since the 1950s, but they weren't always standardized. Early VINs varied wildly in length and format across manufacturers — some were 8 characters, others 13, and each brand had its own scheme.

• 1954 — The American auto industry begins using VINs, but each manufacturer creates its own format.
• 1969 — The U.S. National Highway Traffic Safety Administration (NHTSA) requires all vehicles sold in the U.S. to have a VIN.
• 1981 — NHTSA standardizes the VIN format at exactly 17 characters, following ISO 3779. This is the system still in use today.
• 1987 — The Anti-Theft Act requires major components (engine, transmission) to carry the VIN for identification.
• 2010 — The model year code cycles back to A, beginning a new 30-year cycle.

Frequently Asked Questions

Can two vehicles have the same VIN?

No. The combination of WMI, VDS, model year, plant code, and sequence number ensures every VIN is globally unique. It's illegal to duplicate a VIN, and doing so is a federal crime in the United States (VIN cloning).

Why are I, O, and Q excluded?

These letters are too easily confused with the numbers 1, 0, and 0/9 when handwritten or printed in certain fonts. Excluding them reduces transcription errors.

Do electric vehicles have VINs?

Yes. Every road-legal vehicle manufactured since 1981 has a 17-character VIN, including EVs, hybrids, and plug-in hybrids. The VDS section (positions 4–8) typically encodes the electrification level and battery information.

Where can I find my VIN?

The most common locations are the driver's side dashboard (visible through the windshield), the driver's door jamb sticker, your vehicle registration, and your insurance card. Read our full guide on where to find the VIN on a car.

Can I tell if a VIN is fake?

The check digit (position 9) catches most fake or mistyped VINs. If the check digit doesn't validate, the VIN is either incorrect or has been tampered with. You can verify any VIN instantly with our free VIN decoder.