Application Identifiers (AIs) are prefixes used in GS1 barcodes. They allow you to include additional information in the barcode.
The AIs are used to distinguish the pieces of information. The numbers in brackets indicate which information follows. For example: (21) stands for serial number, and then the serial number follows.
Common AIs are:
- Article code/GTIN: AI (01) - numeric, 14 positions. Example: 05410013111009
- Lot/batch number: AI (10) - alphanumeric, 20 positions. Example: ABC123..
- Serial number: AI (21) - alphanumeric, 20 positions. Example: 12345678..
- Expiry date: AI (17) - YYMMDD, 6 positions. Example: 230527
- Production date: AI (11) - YYMMDD, 6 positions. Example: 180320
More information on the various Application Identifiers and their structure can be found in Chapter 3 of the GS1 General Specifications.