What are the WMI, VDS, and VIS sections?

The WMI is positions 1 to 3 and identifies the manufacturer and country. The VDS is positions 4 to 9 and describes the vehicle attributes plus the check digit. The VIS is positions 10 to 17 and carries the model year, plant code, and serial number.

Which character is the manufacturer?

Positions 1 to 3 form the World Manufacturer Identifier. The first character is the region and country, the second narrows the manufacturer, and the third often indicates the vehicle type or division. The tool looks up common WMIs by name.

Where is the model year in a VIN?

Position 10 encodes the model year on a 30-year repeating cycle. Position 11 is usually the assembly plant. The tool labels both, and a separate model-year decoder resolves the exact year from that single character.

What is the serial number portion?

The last several characters of the VIS, typically positions 12 to 17, are the sequential production serial that uniquely identifies the individual unit coming off the line. They are assigned in build order by the plant.

Does this work for motorcycles and trucks?

The WMI, VDS, VIS structure is standardized for all road vehicles built to ISO 3779, including motorcycles and heavy trucks. The position roles are the same, though manufacturers vary in how they pack attributes into the VDS.

VIN Structure Decoder

A VIN looks like a random string, but it is three structured blocks. This decoder splits any 17-character VIN into its World Manufacturer Identifier, Vehicle Descriptor Section, and Vehicle Identifier Section, then labels what every single character is for, with a built-in lookup for common manufacturers.

How it works

The ISO 3779 standard fixes which positions belong to each section, so the split is purely positional:

positions 1–3   WMI  — region, country, manufacturer
positions 4–8   VDS  — vehicle attributes (body, engine, model)
position  9     VDS  — check digit
positions 10–17 VIS  — 10 model year · 11 plant · 12–17 serial

The tool reads the first three characters against a table of well-known WMIs to name the maker, and it marks position 9 and position 10 specially because they carry the check digit and model year.

Example and tips

In the VIN 1HGCM82633A004352, 1HG is the WMI for Honda in the USA, CM826 is the descriptor section, 3 is the check digit, 3 at position 10 is the model year, A is the plant, and 004352 is the serial. If the WMI is not in the built-in list the tool still labels every position; only the manufacturer name is left blank, which is normal for less common makers.