How to Read a VIN
A Vehicle Identification Number is not a random serial string — it is a fixed-width record where every position carries a specific piece of information. This guide walks through all 17 positions, then derives the 9th-character check digit by hand so you can verify any VIN yourself.
The 17 characters at a glance
1HGCM82633A004352
This example is a 2003 Honda Accord, 2.4L 4-cylinder. The highlighted 9th character is the check digit, derived below.
Why the letters I, O and Q never appear
North American manufacturers deliberately excluded three letters from the alphabet used in VINs. I and O look like 1 and 0, and Q is easily confused with 0. That leaves 23 letters plus 10 digits — 33 possible characters per position. Any VIN containing an I, O or Q is invalid, and finding one is often the fastest way to spot a misread character.
What each position means
Position 1: Country of origin
A single character that tells you where the vehicle was built. 1, 4 and 5 are the United States, 2 is Canada, 3 is Mexico, W is Germany, J is Japan, L is China, K is South Korea, and S covers the UK, Spain and Poland.
Position 2: Manufacturer
The second and third characters, taken together with the first, form the World Manufacturer Identifier (WMI). Together the first three characters identify the brand and sometimes the subsidiary or plant group.
Position 3: Vehicle type or division
Often the vehicle type within the manufacturer range, or the manufacturing division. For cars in North America this is commonly a passenger car, though trucks and multi-purpose vehicles also use the range.
Position 4: Body style
The restraint and body configuration. In North American passenger cars the common values are 1 and 2 for sedans, 3 and 4 for coupes and convertibles, 5 for hatchbacks, 6 for sedans and coupés, 7 for station wagons, and 8 for pickups.
Position 5: Engine
The engine type, though only loosely — VINs commonly reuse a code across several engine variants, so this alone is not enough to identify a specific engine. Decode the VIN to get displacement, configuration and fuel type.
Position 6: Model year
The model year, on a repeating cycle. Letters A–Y run 1980–2000, then 1–9 run 2001–2009, A–Y run 2010–2020, and 1–9 run 2021–2029. A letter never means 0, which is why 0 never appears here.
Position 7: Plant of assembly
The specific factory that built the vehicle. Manufacturers reuse codes between plants, so this is a useful cross-check rather than a definitive answer.
Position 8: Serial number
The first six digits of the vehicle serial number. Combined with positions 12–17 it gives the build sequence within that model year.
Position 9: Check digit
A single character that mathematically validates the other 16, so a mistyped or fabricated VIN is caught. The 9th position is the only one in the VIN that is not a direct data field. The next section works through it.
Position 10: Model year
The model year again, from the same cycle as position 6. Repeating the year is redundant by design — the redundancy is part of what makes accidental transcription errors detectable.
Position 11: Plant of assembly
The plant code again, mirroring position 7 for the same reason.
Position 12: Serial number continued
The vehicle serial number continues, filling positions 8 and 12–17 with the model-year-specific sequence.
Position 13: Serial number continued
Part of the vehicle serial number.
Position 14: Serial number continued
Part of the vehicle serial number.
Position 15: Serial number continued
Part of the vehicle serial number.
Position 16: Serial number continued
Part of the vehicle serial number.
Position 17: Serial number continued
The final character of the vehicle serial number, and the 17th character of the VIN.
The 9th character: ISO 3779 check digit
The check digit is an ISO 3779 checksum that covers the other 16 characters. It catches roughly 99.9% of transcription errors, which is why it is the fastest integrity test for a VIN you just read off a door jamb.
Step 1 — assign each letter a value
Digits keep their own value. Letters are translated using a fixed table. Notice the irregular part: P is 7 (Q is skipped) and R is 9 (S is skipped), because the missing I, O and Q shift everything after them.
| A=1 | B=2 | C=3 | D=4 | E=5 | F=6 |
| G=7 | H=8 | J=1 | K=2 | L=3 | M=4 |
| N=5 | P=7 | R=9 | S=2 | T=3 | U=4 |
| V=5 | W=6 | X=7 | Y=8 | Z=9 |
Step 2 — multiply by the position weight
| 8 | 7 | 6 | 5 | 4 | 3 | 2 | 10 | 0 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 |
Step 3 — add the products, then take the remainder
| Pos | Char | Value | × | Product |
|---|---|---|---|---|
| 1 | 1 | 1 | 8 | 8 |
| 2 | H | 8 | 7 | 56 |
| 3 | G | 7 | 6 | 42 |
| 4 | C | 3 | 5 | 15 |
| 5 | M | 4 | 4 | 16 |
| 6 | 8 | 8 | 3 | 24 |
| 7 | 2 | 2 | 2 | 4 |
| 8 | 6 | 6 | 10 | 60 |
| 9 | 3 | 3 | 0 | 0 |
| 10 | 3 | 3 | 9 | 27 |
| 11 | A | 1 | 8 | 8 |
| 12 | 0 | 0 | 7 | 0 |
| 13 | 0 | 0 | 6 | 0 |
| 14 | 4 | 4 | 5 | 20 |
| 15 | 3 | 3 | 4 | 12 |
| 16 | 5 | 5 | 3 | 15 |
| 17 | 2 | 2 | 2 | 4 |
| Total | 311 | |||
Divide the total by 11 and keep the remainder. The remainder is the check digit; if it comes out as 10, write X instead.
311 ÷ 11 = 28 remainder 3
The remainder is 3, which matches the 9th character of the VIN. The VIN checks out. Change any single character and the sum will almost never land on 3.
One caveat: ISO 3779 was written for North American VINs. Vehicles built for other markets often fail this test even when the VIN is perfectly valid, so a failure is strong evidence of a typo but weak evidence of a bad VIN.
Where to find the VIN on your vehicle
- Driver-side door jamb — a sticker or stamped plate, visible with the door open. This is the most reliable location.
- Lower edge of the windscreen, on the passenger side, readable from outside the vehicle.
- Engine block, usually stamped towards the front of the engine bay.
- Driver door frame or the body panel immediately ahead of the door lock.
- For trailers, on a plate near the front left corner or on the frame rail.
- For motorcycles, stamped on the steering head just below the handlebars, and usually duplicated on the frame.
Skip the arithmetic — decode it instantly
The scanner validates the check digit for you, then resolves the VIN against the NHTSA record to show make, model, year, body class, drive type, engine, displacement, fuel type and transmission.
Decode a VIN