Resources and Education for the GS1-128 symbology
SSCC-18 Barcodes
Application Identifier (AI)
The AI “00” indicates the SSCC-18 data structure will follow.
Extension Digit
The Extension Digit has no defined logic and is used to increase the capacity of the Serial Reference
GS1 Company Prefix
GS1 Company Prefixes are 7-10 digits. Serial Reference Numbers are 6-9 digits.
Serial Reference
The Serial Reference number is assigned by the holder of the GS1 Company Prefix to uniquely identify a shipping container (logistic unit). A Serial Reference cannot be reused for a minimum of 12 months. The combined length of the GS1 Company Prefix and Serial Reference is always 16 digits.
Check Digit
Calculated using the Modulo 10 algorithm. Use a free Check Digit Calculator offered by Bar Code Graphics.