What is Code 128 used for?

Code 128 is used for internal SKU tracking, bin labeling, and encoding alphanumeric data in warehouses and fulfillment workflows.

How is Code 128 different from UPC?

Code 128 supports both letters and numbers, making it ideal for internal SKUs and operational labels. UPC is numeric only and required for retail sales and marketplaces.

When should I use Code 128?

Use Code 128 for internal identifiers, small-format shelf labels, and operational barcodes where GTIN compliance isn’t required.

Is Code 128 accepted by retail marketplaces?

No, Code 128 is not GTIN-compliant and is generally not accepted by external marketplaces like Amazon or Walmart. Use UPC or EAN for those cases.

How does SKUGen help with Code 128?

SKUGen generates structured SKUs that can be encoded as Code 128 barcodes, simplifying label printing, inventory scanning, and variant tracking.

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What Is Code 128 and When Should You Use It Instead of UPC?

Code 128 is a versatile barcode format used widely in warehouse operations, internal inventory systems, and product labeling. Unlike UPCs, which are standardized for external retail use, Code 128 barcodes are flexible and better suited for encoding custom identifiers like SKUs, location codes, or alphanumeric IDs.

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What Makes Code 128 Different?

Code 128 supports a wide range of characters, including both letters and numbers. This allows businesses to encode more complex data such as internal SKUs (e.g., “SKU-RED-M”), bin locations, or special inventory codes directly into a barcode. It also creates a more compact barcode, making it easier to print on smaller labels.

In contrast, UPC-A and EAN-13 barcodes only encode numeric values, and are designed for global product identification.

When to Use Code 128

Use Code 128 when you need to:

Encode alphanumeric SKUs
Print labels for warehouse bins, pick locations, or internal tags
Include internal identifiers that do not conform to GTIN standards
Create compact barcodes for small-format shelf labels

This makes Code 128 ideal for operational workflows where barcode readability, speed, and internal control matter more than marketplace compliance.

SKUGen integrates seamlessly with this approach. It allows you to generate structured, variant-level SKUs that can be encoded into Code 128 barcodes for internal use across shelf labels, pick lists, or receiving tasks.

When Not to Use Code 128

Code 128 is not a replacement for UPC or EAN barcodes when a product is being sold through third-party retailers, online marketplaces, or global distributors. Those platforms often require standardized, registered barcodes (GTINs), which Code 128 does not provide.

In short, use UPC or EAN for external selling, and use Code 128 for internal speed and control.

Code 128 vs UPC for internal SKU barcodes

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