Technical Specifications
- Standard
- ISO/IEC 15417
- Character Set
- Full ASCII 128 (Letters, numbers, punctuation, control chars)
- Subsets
- Code 128A (Caps/Control), Code 128B (ASCII), Code 128C (Double-density numeric pairs)
- Checksum
- Modulo 103 check character (calculated automatically)
- Quiet Zones
- 10X minimum on both ends
Standard Industry Use Cases
- Warehouse bin and pallet rack labeling
- Shipping container and carton tracking (UCC/EAN-128)
- Enterprise asset tags and equipment serial numbers
- Medical laboratory specimen tube labeling
Key Benefits of Code 128
Useful for Internal Identifiers
Create Code 128 graphics for identifiers you control. Confirm any customer, carrier, or platform requirements before production use.
Full 128 ASCII Alphanumeric Range
Encodes letters (A–Z, a–z), numbers (0–9), punctuation, and control characters.
Auto-Switching High Density
Automatically switches between subsets A, B, and C to compress paired digits into compact spaces.
What Code Do I Need for My Product? (Customer Decision Guide)
Choosing the right barcode format depends on where your product is sold, the packaging substrate, and scanner infrastructure:
Labeling warehouse shelves, bins, and pallets?
Code 128 is the industry gold standard for warehouse management systems (WMS) and internal logistics.
Tracking company IT assets, tools, or serialized parts?
Use Code 128 to encode alphanumeric serial numbers (e.g. LAPTOP-2026-X8) onto durable sticker labels.
Can I use Code 128 at a grocery store checkout?
Standard supermarket cash registers expect 12-digit UPC or 13-digit EAN; use Code 128 for logistics, shipping, and internal operations.
Code 128 Usage Guidelines & Quiet Zone Rules
- Code 128 is an open public-domain standard (ISO/IEC 15417). No royalties or company prefix registrations are required for private or internal use.
- When using GS1-128 (formerly UCC/EAN-128) in commercial freight, you must format data with official GS1 Application Identifiers (AIs) and start with an FNC1 character.
- Ensure a minimum quiet zone of 10 times the module width (10X) on both ends of the barcode to allow laser scanners to synchronize timing.
Frequently Asked Questions
What characters can I encode into a Code 128 barcode?
Code 128 can encode all 128 standard ASCII characters, including uppercase letters, lowercase letters, numbers, punctuation symbols, and control codes.
Does your engine use Code 128 subset C for numeric data?
Yes. Our engine uses automatic optimization to switch into Code 128C whenever strings of digits appear, compressing two numeric digits into a single barcode character for maximum compactness.