VIN Structure Explained: WMI, VDS, and VIS

The three sections

A modern VIN has 17 characters. Positions 1–3 are the World Manufacturer Identifier (WMI), positions 4–9 are the Vehicle Descriptor Section (VDS), and positions 10–17 are the Vehicle Identifier Section (VIS). The letters I, O, and Q are never used, to avoid confusion with 1 and 0.

Extracting It Automatically

When you read this data from photos, the VIN OCR API returns it as structured JSON, and you can apply the rules on this page as validation. Try it with the free scanner.

Where This Fits

• World Manufacturer Identifier: The first character indicates the region or country of manufacture (for example 1, 4, or 5 for the United States, 2 for Canada, 3 for Mexico, J for Japan, K for Korea, W for Germany). Together with characters 2 and 3 it identifies the manufacturer and often the vehicle type.
• Vehicle Descriptor Section: Positions 4–8 describe model, body, engine, and restraint details in a manufacturer-specific way. Position 9 is the check digit in North American VINs.
• Vehicle Identifier Section: Position 10 encodes the model year, position 11 usually identifies the assembly plant, and positions 12–17 are the production sequence number.

Extract It with the API

Read the document from a photo and validate the returned fields.

Prerequisite: Python 3.9+, `pip install requests`, and a STRUCTOCR_API_KEY

import base64
import os
import requests

with open("vin.jpg", "rb") as image_file:
    image = base64.b64encode(image_file.read()).decode("ascii")

response = requests.post(
    "https://api.structocr.com/v1/vin",
    headers={"x-api-key": os.environ["STRUCTOCR_API_KEY"]},
    json={"img": image},
    timeout=30,
)
response.raise_for_status()
data = response.json()["data"]
print("vin:", data.get("vin"))
print("confidence:", data.get("confidence"))
print("carrier_type:", data.get("carrier_type"))

Reference Summary

Key facts from this page in structured form, for quick lookup.

{
  "The three sections": "A modern VIN has 17 characters.",
  "World Manufacturer Identifier": "The first character indicates the region or country of manufacture (for example 1, 4, or 5 for the United States, 2 for Canada, 3 for Mexico, J for Japan, K for Korea, W for Germany).",
  "Vehicle Descriptor Section": "Positions 4–8 describe model, body, engine, and restraint details in a manufacturer-specific way.",
  "Vehicle Identifier Section": "Position 10 encodes the model year, position 11 usually identifies the assembly plant, and positions 12–17 are the production sequence number.."
}