VIN Decoder: What Each of the 17 Characters Means

A modern VIN has 17 characters in three parts. Characters 1-3 identify the manufacturer and vehicle type. Characters 4-8 describe the vehicle (model line, body, engine, restraints and similar attributes). Character 9 is a check digit. Character 10 is the model year, 11 is the assembly plant and 12-17 are the production sequence number. The rules come from federal regulation 49 CFR Part 565 in the U.S. and CMVSS 115 in Canada. A decoder turns those codes into a year, make and model, but it says nothing about what happened to the car after it left the factory.

The 17 positions at a glance

The rules quoted on this page are current as of October 2026. Regulations can be amended, so check the official text before you rely on a detail. The structure below is set out in 49 CFR 565.15. Industry shorthand often calls positions 1-3 the WMI (World Manufacturer Identifier), 4-8 the VDS (Vehicle Descriptor Section) and 10-17 the VIS (Vehicle Identifier Section).

Some general rules apply to every position. Under 49 CFR 565.13, a VIN uses only the digits 0-9 and the capital letters A-Z except I, O and Q, and every one of the 17 spaces must be filled. So a character that looks like an "O" in a VIN is a zero, and one that looks like an "I" is a one. The same section says that no two vehicles from the 1980 model year onward, made within a 60-year period, may have the same VIN.

Positions 1-3: the World Manufacturer Identifier

For a manufacturer building 1,000 or more vehicles of a given type a year, the first three characters identify the manufacturer and vehicle type. One building fewer than 1,000 uses a "9" in position 3 and completes its identifier in positions 12-14. Those definitions are in 49 CFR 565.12.

WMIs are assigned by SAE International. NHTSA's Manufacturer Information Database in vPIC lets you look them up. In vPIC, each WMI is listed with a country, and the first character follows that country. The vPIC records for two automakers show the pattern:

In these examples, 1, 4 and 5 are U.S. manufacturers, 2 is Canadian, 3 is Mexican and J is Japanese. The WMI identifies the manufacturing entity that assigned the VIN. It does not necessarily tell you where that particular car was assembled, because position 11 identifies the plant.

Positions 4-8: what the vehicle is

These five characters are coded by the manufacturer, so the same character means different things for different brands. The regulation only fixes which attributes have to be represented. In summary, from 49 CFR 565.15(b):

• Passenger cars: make, line, series, body type, engine type, and all restraint devices and their locations.
• Multipurpose passenger vehicles (MPVs): make, line, series, body type, engine type and gross vehicle weight rating (GVWR), plus restraint devices at 10,000 lb (4,536 kg) GVWR or less.
• Trucks: make, model or line, series, chassis, cab type, engine type, brake system and GVWR, plus restraint devices at 10,000 lb GVWR or less.
• Buses, trailers, motorcycles, incomplete vehicles and low-speed vehicles each have their own list.

Manufacturers must send NHTSA the information needed to decipher their VINs at least 60 days before they offer the first vehicle with that coding for sale (49 CFR 565.16). That is why a free government decoder can turn positions 4-8 into a specific model, body and engine.

Position 9: the check digit, with a worked example

The check digit lets anyone confirm that a VIN was copied correctly. You recalculate it from the other 16 characters, and if the result doesn't match, at least one character is wrong. The method is in 49 CFR 565.15(c).

Step 1: convert letters to numbers

Digits keep their own value. Letters are converted using this table. I, O and Q do not appear because they are never used.

Step 2: multiply by the position weight

Each position has a fixed weight. Position 9 has no weight because it holds the answer.

Step 3: add, divide by 11, read the remainder

Add all 16 products and divide the sum by 11. The remainder (0 to 10) is the check digit. A remainder of 10 is written as the letter X.

Worked example: the sample VIN from the regulation

The regulation itself uses the sample VIN 1G4AH59H_5G118341, with position 9 left blank. Here is the full calculation, which we re-checked by hand:

The products add up to 411. Since 11 × 37 = 407, 411 divided by 11 leaves a remainder of 4. The check digit is 4, so the complete VIN is 1G4AH59H45G118341. This matches the result printed in the regulation.

A matching check digit only means the VIN is internally consistent. It does not prove the VIN belongs to the car in front of you, or that the car has a clean history. If the check fails, re-read the plate first, because a typo is the usual cause. If the VIN on the car itself fails, ask questions before buying.

Position 10: the model year code table

Position 10 uses a cycle of 30 characters. It skips I, O and Q (never allowed in a VIN) as well as U, Z and the digit 0. After 30 years the cycle starts again, which is why "A" can mean 1980 or 2010. The table combines Table XIII of 49 CFR 565.25 (model years 1980-2009) and Table VII of 49 CFR 565.15 (through 2039).

How position 7 tells you which cycle applies

For passenger cars, and for MPVs and trucks with a GVWR of 10,000 lb (4,536 kg) or less, 49 CFR 565.15 gives a tiebreaker. If position 7 is a number, the model year in position 10 falls in 1980-2009. If position 7 is a letter, it falls in 2010-2039. So with "C" in position 10, a digit in position 7 means 1982 and a letter means 2012. The rule does not cover heavier trucks, buses, trailers or motorcycles. For those, use the title or a decoder.

The model year is not always the calendar year of production. The regulation defines it as the year the manufacturer uses to designate the model, regardless of when it was built, as long as the production period does not exceed 24 months. A car built in autumn 2026 can carry a "V" (2027).

Positions 11-17: plant and serial number

Position 11 identifies the plant where the VIN was affixed. Manufacturers assign these codes, so you need a decoder to translate them. Positions 12-17 are the production sequence number for manufacturers that build 1,000 or more vehicles of a type a year. For low-volume makers, positions 15-17 hold the sequence number. Under 49 CFR 565.15(d), the last five characters must be numeric for passenger cars and for MPVs and trucks of 10,000 lb GVWR or less. For other vehicle types, the last four must be numeric.

How to decode your VIN, step by step

1. Copy the VIN from the car itself. Read it through the lower left of the windshield and compare it with the door-jamb label and the paperwork (locations below).
2. Check the length and characters. There should be exactly 17 characters and no I, O or Q. An "O" is a zero and an "I" is a one.
3. Read positions 1-3. Look up the WMI in NHTSA's vPIC Manufacturer Information Database to confirm the manufacturer and vehicle type.
4. Find the model year. Look at position 10 in the table above, then use position 7 to pick the cycle if it's a car or light truck.
5. Verify the check digit. Do the calculation above, or let a decoder do it. If it fails, re-check your transcription first.
6. Decode positions 4-8 and 11. These are manufacturer-specific. NHTSA's free vPIC VIN decoder translates them using the data manufacturers report.
7. Compare the result with the car and the ad. Body style, engine, drivetrain and model year should match what the seller describes.

When you enter a VIN on the VIN Data Hub check page, the free preview shows the decoded vehicle and how many records were found in each report category, before you decide whether to buy the full report.

Where to find the VIN on a car

• Lower left of the windshield. On passenger cars, MPVs and trucks of 10,000 lb GVWR or less, the VIN must be inside the passenger compartment. It has to be readable through the glass, near the left windshield pillar, by someone standing outside, in characters at least 4 mm high (49 CFR 565.13). NHTSA's recalls page also tells owners to look there first.
• Driver's door jamb. The federal certification label must include the VIN. It goes on the hinge pillar, the door-latch post or the door edge next to the driver's seat, with fallbacks if none of those is practicable (49 CFR 567.4).
• Paperwork. NHTSA notes the VIN is on your registration card and may be on your insurance card.

All of these should show the same 17 characters. If they don't agree, find out why before you go any further.

Canada uses the same structure

Canada sets its VIN rules in section 115 of the Motor Vehicle Safety Regulations (C.R.C., c. 1038). They require a 17-character VIN with a check digit in position 9 and a model year code in position 10, a 60-year uniqueness rule and a VIN readable through the windshield on light vehicles. Decoding works the same way. Note that NHTSA's vPIC says its data covers vehicles intended for sale or importation into the United States. For Canada-specific records, see our guide on how to check a VIN in Canada.

Pre-1981 vehicles are different

The fixed 17-character format starts with the 1981 model year. Earlier vehicles used manufacturer-specific serial or VIN formats that don't follow the position rules on this page. NHTSA's vPIC says it is intended for model years 1981 and later and does not decode vehicles from before the 1980s VIN standard. Its decoder rejects pre-1981 years.

What a VIN decoder cannot tell you

A decoder reads a number fixed at the factory, so everything it returns describes the car as built. It cannot tell you whether the car has a branded title, was reported stolen, went through a salvage auction, sold with consistent odometer readings, or what it is worth today. That information comes from records created after the car was sold, not from the VIN itself. Our explainer on free VIN checks versus vehicle history reports covers the difference in detail, and how to read a vehicle history report explains what to look for once you have one.

The paid VIN Data Hub report adds a title check (salvage yes/no with cause and date), a theft check, salvage auction and damage records, past sales and listing history with a mileage-inconsistency flag, NHTSA recall campaigns for the make, model and year, and U.S. market value estimates. It does not include accident or police reports, insurance claims, service records, the number of owners, liens or Canadian provincial records, and its recall section is not an open-recall status for your specific VIN. Current prices are on the pricing page.

Frequently asked questions

What does the 10th digit of a VIN mean?

The 10th character is the model year code. It runs through a 30-character cycle (A through Y without I, O, Q, U and Z, then 1 through 9), so "A" means 1980 or 2010, "S" means 1995 or 2025 and "T" means 1996 or 2026. On passenger cars and light trucks, a letter in position 7 means the newer 2010-2039 cycle and a digit in position 7 means 1980-2009.

How do I calculate a VIN check digit?

Convert each letter to its number (A=1 through H=8, J=1 through N=5, P=7, R=9, S=2 through Z=9), multiply each of the 16 values by its position weight (8, 7, 6, 5, 4, 3, 2, 10, skip position 9, then 9, 8, 7, 6, 5, 4, 3, 2), add the products and divide by 11. The remainder is the check digit, and a remainder of 10 is written as X.

Can a VIN contain the letters I, O or Q?

No. The federal VIN rule allows the digits 0-9 and the capital letters A-Z except I, O and Q. In practice, if a VIN looks like it contains an O, it is a zero, and an apparent I is a one.

What does the first character of a VIN tell you?

It starts the World Manufacturer Identifier and reflects the country of the manufacturer that assigned the VIN. In NHTSA's vPIC data, for example, U.S. manufacturers' identifiers start with 1, 4 or 5, Canadian ones with 2, Mexican ones with 3 and Japanese ones with J.

Can a VIN decoder show accidents or title problems?

No. A decoder only translates what the manufacturer encoded at the factory, such as year, make, model, body, engine and plant. Title brands, theft records, auction damage and past sales come from separate databases and need a vehicle history report.

Do cars made before 1981 have 17-character VINs?

Not under a common standard. The fixed 17-character format applies from the 1981 model year, and earlier vehicles used manufacturer-specific formats that standard decoders such as NHTSA's vPIC do not decode.

Related: Why check a VIN before buying · How to check car recalls by VIN in the U.S. and Canada · How to check for a salvage title