GS1-128 (เดิมคือ UCC/EAN-128): แกนหลักของห่วงโซ่อุปทาน
Technical guide to GS1-128: FNC1 prefix, application identifier structure, date formats, serial numbers, and SSCC pallet labeling.
GS1-128: The Supply Chain Workhorse
gs1-128-term/" class="glossary-term-link" data-term="GS1-128" data-definition="Code 128 subset with GS1 Application Identifiers for supply chains." data-category="1D Linear Symbologies">GS1-128 (formerly UCC/EAN-128) is the standard barcode for supply chain logistics, built on Code 128 with the addition of FNC1 function characters and GS1 Application Identifier data structures. It appears on every compliant shipping label, pallet, and case in global commerce.
How GS1-128 Differs from Code 128
GS1-128 is Code 128 with two critical additions:
- FNC1 after start: The first character after the Code 128 symbology and scan direction." data-category="Barcode Anatomy & Structure">start character must be FNC1 (Function Code 1). This signals to the scanner that the data follows GS1 AI syntax
- Application Identifiers: The data is structured into fields, each prefixed by a numeric AI that defines the field type and format
Without FNC1, it is just Code 128. With FNC1, it is GS1-128.
Application Identifiers
AIs are the data dictionary of the GS1 system. The most commonly used:
| AI | Field | Format | Fixed/Variable |
|---|---|---|---|
| (00) | SSCC | 18 digits | Fixed |
| (01) | GTIN | 14 digits | Fixed |
| (02) | Content GTIN | 14 digits | Fixed |
| (10) | Batch/Lot | 1-20 alphanum | Variable |
| (11) | Production date | YYMMDD | Fixed |
| (17) | Expiry date | YYMMDD | Fixed |
| (21) | Serial number | 1-20 alphanum | Variable |
| (37) | Quantity | 1-8 digits | Variable |
FNC1 as Field Separator
Fixed-length fields do not need separators because the parser knows exactly how many characters to read. Variable-length fields are followed by FNC1 (unless they are the last field in the barcode). FNC1 renders as GS (ASCII 29) when transmitted by the scanner.
SSCC Pallet Labels
The most important GS1-128 application is the shipping label with Serial Shipping Container Code:
(00) 1 06141411234567897
| |_______________|
| SSCC digits
Extension digit
SSCC labels follow the GS1 logistics label layout with three sections: shipping information, barcode area, and human-readable data.
Concatenation
Multiple AIs can be encoded in a single GS1-128 barcode:
(01)09506000134352(17)251231(10)ABC123
This encodes GTIN, expiry date, and batch number in one symbol.
Practical Guidelines
- Maximum symbol length: 165mm (including quiet zones)
- Minimum X dimension: 0.495mm for supply chain applications
- Quiet zones: 10X minimum on each side
- Human-readable text must show AI in parentheses: (01)09506000134352
- Test with trading partners' scanning systems before production rollout
- Use GS1-128 label generation tools to ensure correct AI formatting