The Ultimate Guide to Code 128 Barcodes

Code 128 is an extremely high-density linear barcode symbology capable of encoding all 128 ASCII characters (including numbers, upper and lower case letters, and symbols). It is the globally recognized standard for logistics, shipping, and supply chain management due to its compactness and versatility.

Why Choose Code 128?

When managing inventory, you often need to encode complex alphanumeric strings like serial numbers, batch codes, or internal SKUs. Code 128 is uniquely suited for this because it can seamlessly switch between three different character sets (A, B, and C) to compress the data, making the resulting barcode physically shorter than other formats like Code 39.

  • High Density: Encodes more data in less space, perfect for small labels.
  • Full ASCII Support: Can encode any character on a standard keyboard.
  • Built-in Error Checking: Includes a mandatory checksum digit for reliable scanning.
  • Universal Compatibility: Scannable by virtually all standard 1D barcode scanners worldwide.

Common Use Cases for Code 128

Because of its flexibility, Code 128 is used across multiple industries:

Warehouse Management (WMS)

Labeling bins, pallets, and shelving units with alphanumeric location codes.

Amazon FBA (FNSKU)

Amazon uses Code 128 for its internal FNSKU labels to track seller inventory.

Shipping & Logistics

Encoding tracking numbers and routing information on courier packages.

Asset Tracking

Tagging IT equipment, tools, and company assets with unique serial numbers.

Code 128 FAQs

Code 128 can encode all 128 ASCII characters, including numbers, uppercase and lowercase letters, and symbols.
Code 128 is much denser than Code 39, meaning it takes up less space for the same amount of data. It also supports a wider range of characters.
While GS1-128 (formerly UCC/EAN-128) uses the Code 128 symbology, it includes special application identifiers (AIs) to format data consistently across the global supply chain. Our generator creates standard Code 128 symbols.