GS1-128 Introduction

The GS1-128 barcode, a subset of the more general Code 128 Symbology, is a continuous, self-checking and bi-directionally decodable linear bar code symbology. By agreement between AIM, Inc. and GS1, use of the Function 1 Symbol Character (FNC1) in Code 128 Symbols in the first symbol character position following the Start Character has been reserved exclusively for the GS1 System.
GS1-128 is also an application standard of Code 128 barcode symbology. The former name is UCC/EAN-128. GS1 128 uses a series of AI (Application Identifiers, defined by GS1 organization) to encode additional data such as weights, prices, best before dates, batch numbers, quantities, and many other information needed by automatic identification and data capture.

OnBarcode provides comprehensive GS1-128 generator components .NET applications.

The structure of GS1-128 is as below:

When GS1-128 size setting is concerned, two factors are of importance: X dimension and barcode width.

Please get details from GS1-128 size setting instruction.

GS1-128 encodable character set:

• Three identical character set as Code 128, as defined by the International ISO/IEC 646 Standard
• Four non-data function characters
• Four code set selection characters (single character code set included)
• Three start characters (Start A, B, C)
• One stop character (13 modules: 1100011101011)

The Human Readable Interpretation of the data in the bar code symbol must be shown below the symbol. Start, Stop, shift, and function characters, as well as the Symbol Check Character, are not shown in the human readable format.

The precise location of the Human Readable Interpretation and the font used to represent the characters are not specified for GS1-128 Bar Code Symbols. However, the characters should be clearly legible (such as OCR-B) and must be obviously associated with the symbol. The Quiet Zones must not be violated.

Application Identifiers should be clearly recognizable to facilitate key entry. This is achieved by putting parentheses around Application Identifiers in the Human Readable Interpretation.