Global Trade Item Number - Format

Format

The numbering structure is as follows:

• T1 - Indicator digit, used for GTIN-14, "1" to "8" indicates a packaging level and "9" a variable measure item. Zero in this position is not considered an Indicator Digit, but rather a pad or fill zero. There is however, no worldwide consensus on which number indicates which packaging level and no significance should be built into this number.
• T2 through T13 GS1 Company Prefix & Item (product or service) reference number. The GS1 Company Prefix is allocated to the member company and the Item Reference is allocated by the user company. The length of each of these elements varies in length depending on the length of the allocated GS1 Company Prefix. Each different type of trade item is allocated a different number and, for ease of administration, it is recommended that companies do this sequentially (001, 002, 003, etc.).
• T14 is a check digit, which follows the standard modulo 10 calculation.

All books and serial publications sold internationally (including those in U.S. stores) have GTIN (GTIN-13) codes. The book codes are either constructed by prefixing the old ISBN 10 number with 978, and recalculating the trailing check digit, or from 1 January 2007 issued as thirteen digits starting with 978 (eventually 979 as the 978 ranges are used up).

Each type of trade item is given its own GTIN, with the understanding that there is a potential need to retrieve pre-defined information from such items; this product or service may be priced, ordered, or invoiced at any point in the supply chain. This includes individual items as well as all of their different packaging configurations.

In February 2005, employees and booksellers of Barnes & Noble were informed that beginning at the end of March, their computer systems were going to add the ability to search by EAN to facilitate a switch over to the EAN (sometimes called ISBN 13 when used for books) from the current standard of ISBN 10 codes. Receipts will now list the EAN number, rather than the ISBN 10 number. Since all existing 10-digit ISBN codes are mapped to a subset of the space of 13-digit EANs, booksellers' computer systems will still be able to search by ISBN (and UPC in the music departments) to help booksellers locate older books that have not been assigned an EAN.

By January 1, 2005 the U.S. ISBN agency requires publishers be able to communicate ISBNs as GTIN-13s. The new 979 prefix for publications will be available on January 1, 2007 or upon eventual assignment of the last 978 prefix.