This page explains how GM VIN decoding works, what information you can realistically get from a 17-character Vehicle Identification Number, and how to verify the results on a real car. If you’re decoding a Chevrolet, you can jump straight to the external tool we link below.
No forms here — this is a long-form guide. When you’re ready to decode, use the button above (or the link in the Chevrolet section).
Jump to the part you need, or read it top-to-bottom like a checklist.
A VIN (Vehicle Identification Number) is a standardized identifier used to describe a specific vehicle. Modern road vehicles typically use a 17-character VIN (letters + digits).
Think of VIN decoding as “identify the build blueprint.” Great for basics, helpful for parts, and useful for spotting mismatches.
If someone claims “VIN proves it never had an accident,” that’s not VIN decoding — that’s wishful thinking with confidence.
General Motors includes multiple brands and platforms. A correct VIN decode helps you answer the practical questions: What is it? What’s under the hood? Where and when was it built?
If your goal is “buy the correct part the first time,” VIN decoding is step one, not the finish line.
Most modern GM vehicles follow the standard 17-character VIN layout. The details of what each character means can vary by brand, model year, and market — but the structural “zones” are consistent.
| Position | Name | Typical meaning | Why it matters |
|---|---|---|---|
| 1–3 | WMI (World Manufacturer Identifier) | Manufacturer + region/country code grouping | Confirms who built it and where the VIN series is registered |
| 4–8 | VDS (Vehicle Descriptor Section) | Series/body/restraints/engine family (varies by GM brand/year) | Helps differentiate similar-looking trims and powertrains |
| 9 | Check digit (mainly North America) | Calculated character to validate VIN integrity | Detects typos and some forms of incorrect VIN entry |
| 10 | Model year code | A code that maps to a model year (cycles every 30 years) | Very common point of mismatch in listings and paperwork |
| 11 | Plant code | Assembly plant identifier (manufacturer-specific mapping) | Useful for traceability; decoders map it to a plant name |
| 12–17 | Serial / production sequence | Vehicle’s sequential build number within that plant/year series | Helps distinguish two otherwise identical VIN patterns |
A useful mindset: WMI = who, VDS = what, VIS = when/where/which unit. The magic is not in a single character — it’s in the combination.
“GM VIN” usually refers to vehicles produced under the General Motors umbrella (commonly Chevrolet, GMC, Cadillac, Buick) and GM-built vehicles across different markets and model years. Because GM has produced many platforms and regional variants, the depth of decoding depends on the VIN database a decoder uses.
The 10th VIN character is commonly used as the model year code. It’s not always the same as the build date, and it cycles every 30 years.
The code sequence runs through letters and digits and then repeats. Commonly excluded letters are I, O, Q, U, Z (to avoid confusion), and 0 is not used as a year code.
If you need the exact build date, look for manufacturer labels, door jamb stickers, and official documentation. Model year ≠ production month.
A can be 1980 or 2010).| Code | Year (cycle 1) | Year (cycle 2) |
|---|---|---|
A | 1980 | 2010 |
B | 1981 | 2011 |
C | 1982 | 2012 |
D | 1983 | 2013 |
E | 1984 | 2014 |
F | 1985 | 2015 |
G | 1986 | 2016 |
H | 1987 | 2017 |
J | 1988 | 2018 |
K | 1989 | 2019 |
L | 1990 | 2020 |
M | 1991 | 2021 |
N | 1992 | 2022 |
P | 1993 | 2023 |
R | 1994 | 2024 |
S | 1995 | 2025 |
T | 1996 | 2026 |
V | 1997 | 2027 |
W | 1998 | 2028 |
X | 1999 | 2029 |
Y | 2000 | 2030 |
1 | 2001 | 2031 |
2 | 2002 | 2032 |
3 | 2003 | 2033 |
4 | 2004 | 2034 |
5 | 2005 | 2035 |
6 | 2006 | 2036 |
7 | 2007 | 2037 |
8 | 2008 | 2038 |
9 | 2009 | 2039 |
Tip: If you’re decoding a modern GM vehicle and the year code could mean “1994 or 2024,” context usually makes it obvious.
On many North American VINs, the 9th position is a check digit used to validate that the VIN is internally consistent. It helps catch typos and “fat-fingered” VINs.
The check digit is computed from the other VIN characters using a standardized weighting algorithm. If a single character is entered wrong, the check digit often won’t match.
Passing a check digit is like spelling a name correctly. Helpful. Not a background check.
For verification, you want the VIN from more than one place. Listings and screenshots are fine for a first pass, but a real check means matching VIN locations on the vehicle and paperwork.
1 vs I, 0 vs O, 5 vs S.GM vehicles often use RPO codes (Regular Production Option codes) to describe factory-installed options and packages. If you’re trying to confirm exact equipment, RPO codes can be more specific than a VIN-only decode.
RPO codes are short alphanumeric codes used by GM to represent individual options and packages.
Depending on model and year, RPO codes may appear on a “Service Parts Identification” label (if present). Placement varies by vehicle.
This is the “do it without drama” workflow. It’s short, practical, and designed to reduce mistakes.
Get the VIN from the windshield plate, the door jamb label, and the paperwork.
Most modern VINs are 17 characters and avoid I, O, and Q.
For Chevrolet VIN decoding, use this external link: Chevrolet VIN decoder.
If your GM vehicle is a Chevrolet and you want to run an actual VIN decode right now, use the linked decoder below.
This button takes you to: https://chevrolet.7zap.com/en/vin-decoder/.
Short answers to the most common questions.
Sometimes only partially. For exact equipment, use RPO option codes (if present) and cross-check with labels and parts catalogs.
They use different databases and have different market/year coverage.
Not exactly. It’s typically the model year code.
Start with copy accuracy: 17 characters, remove spaces, and double-check look-alike characters.
Use the external Chevrolet decoder link, then verify year + configuration using this guide.