GS1-128-Etikettengeneration: Ein Entwicklerleitfaden

GS1-128 Label Generation: Building Compliant Shipping Labels

GS1-128 labels are the standard for supply chain logistics, appearing on every compliant shipping case and pallet. Generating these labels correctly requires understanding 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 barcodes." data-category="GS1 Standards & Identifiers">Application Identifier formatting, label layout standards, and print quality requirements.

GS1 Logistics Label Layout

The GS1 logistics label (also called the GS1 transport label or SSCC label) follows a standardized three-section layout:

Top section: Human-readable shipping information (ship-from, ship-to addresses, PO number, carrier information)

Middle section: Supplementary barcodes and data (GTIN, quantity, batch, expiry)

Bottom section: The primary GS1-128 barcode encoding the SSCC, with human-readable AI data

Application Identifier Formatting

When generating the barcode data string, follow these rules:

1. Start with FNC1 (this makes it GS1-128 rather than plain Code 128)
2. Concatenate AIs and their values in sequence
3. Use FNC1 (transmitted as GS, ASCII 29) to separate variable-length fields
4. Fixed-length fields do not need separators

Example for a pallet label:

FNC1 + (00)106141412345678903 + (02)10614141000012 + (37)00000024 + FNC1 + (17)261231 + (10)BATCH456

SSCC Generation

The Serial Shipping Container Code is the primary identifier on logistics labels:

• AI (00): Always 18 digits
• Structure: Extension digit (1) + GS1 Company Prefix + Serial Reference + Check digit
• Each SSCC must be globally unique and never reused

Label Dimensions

Barcode Specifications

For the GS1-128 barcode on logistics labels:

• X dimension: 0.495mm minimum (SC 5), 0.5mm target
• Height: 32mm minimum
• Maximum length: 165mm including quiet zones
• Quiet zones: 10X on each side (minimum 5mm)
• Human-readable: AIs in parentheses, OCR-B font recommended

Print Quality

Logistics labels must meet ISO/IEC 15416" data-definition="International standard grading linear barcode print quality A-F." data-category="Printing & Quality">ISO/IEC 15416 quality standards:

• Minimum grade: C (1.5) for general supply chain
• Grade B (2.5) or higher recommended
• Use thermal transfer printing for durability
• Verify with a barcode verifier, not just a scanner
• Test labels on actual carton/pallet surfaces

Common Mistakes

• Missing FNC1: Omitting the initial FNC1 creates a Code 128 barcode, not GS1-128
• Wrong field separators: Using FNC1 after fixed-length fields (unnecessary) or omitting it after variable-length fields (causes parsing errors)
• Check digit errors: Miscalculating SSCC or GTIN check digits
• Quiet zone violations: Printing too close to the label edge or adjacent labels
• Label placement: Placing the label where it will be wrapped around a corner or covered by strapping

Printer Selection

For GS1-128 logistics labels, use industrial thermal transfer printers:

• Resolution: 203 DPI minimum, 300 DPI recommended
• Print width: 4 inches minimum for case labels, 6+ inches for pallet labels
• Speed: Match to your labeling throughput requirements
• Connectivity: Network (Ethernet/Wi-Fi) for centralized management