Vehicle Identification Number

VIN - Vehicle Identification Number; a unique serial number assigned to every automobile by its manufacturer.

A unique serial number used by the automotive industry to identify individual motor vehicles. Prior to 1981, there was no accepted standard for these numbers, so different manufacturers used different formats. Since 1981, VINs consist of 17 characters which do not include the letters I (i), O (o), or Q (q) (to avoid confusion with numerals 1 and 0). There are vehicle history services in several countries that can help potential car owners use VINs to find lemons and branded vehicles. See the used car article for a list of countries where this service is available.

The first three characters uniquely identify the manufacturer of the vehicle using the World Manufacturer Identifier or WMI code. A manufacturer who builds fewer than 500 vehicles per year uses a 9 as the third digit, and the 12th, 13th and 14th position of the VIN for a second part of the identification. Some manufacturers use the third character as a code for a vehicle category (e.g., bus or truck), a division within a manufacturer, or both.

The first character of the WMI is the region in which the manufacturer is located. In practice, each is assigned to a country of manufacture. The 4th to 9th positions in the VIN are the Vehicle Descriptor Section or VDS. This is used, according to local regulations, to identify the vehicle type, and may include information on the automobile platform used, the model, and the body style. Each manufacturer has a unique system for using this field. Most manufacturers since the 1980s have used the 8th digit to identify the engine type whenever there is more than one engine choice for the vehicle. Example: for the 2007 Chevrolet Corvette U= 6.0L V8, E= 7.0L V8.

The 10th to 17th positions are used as the Vehicle Identifier Section or VIS. This is used by the manufacturer to identify the individual vehicle in question. This may include information on options installed or engine and transmission choices, but often is a simple sequential number. In North America, the last five digits must be numeric. One consistent element of the VIS is the 10th digit, which is required worldwide to encode the model year of the vehicle. Besides the three letters that are not allowed in the VIN itself (I, O and Q), the letters U and Z and the digit 0 are not used for the model year code. Note that the year code is the model year for the vehicle.

The year 1980 was encoded by some manufacturers, especially General Motors and Chrysler, as "A" (since the 17-digit VIN wasn't mandatory until 1981, and the "A" or zero was in the manufacturer's pre-1981 placement in the VIN), yet Ford and AMC still used a zero for 1980. Subsequent years increment through the allowed letters, so that "Y" represents the year 2000. 2001 to 2009 are encoded as the digits 1 to 9, and subsequent years are encoded as "A", "B", "C", etc.

Another consistently-used element (which is compulsory in North America) is the use of the 11th character to encode the factory of manufacture of the vehicle. Although each manufacturer has their own set of plant codes, their location in the VIN is standardized.