A SKU (stock-keeping unit) is an internal code created by a retailer to manage inventory, identify products, and streamline warehouse and label printing operations.

A UPC (Universal Product Code) is a standardized 12-digit barcode used globally for external product identification, particularly for retail, POS systems, and marketplaces.

Should I use both a SKU and a UPC?

Yes, using both is ideal. SKUs help with internal operations like inventory and picking, while UPCs ensure external systems can recognize your product.

What tool can help generate SKUs and UPCs?

The WebshopAssist SKU Generator App helps you create structured SKUs and assign barcodes for each product and variant.

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SKU vs UPC: What’s the Difference and Which Should You Use?

When managing retail inventory, it’s essential to understand the difference between a SKU and a UPC. While both are identifiers used to track and label products, they serve very different purposes.

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What Is a SKU?

A SKU, or stock-keeping unit, is an internal product code created by the retailer. SKUs are designed for internal use—they help staff identify items, manage inventory, process orders, and print labels. A SKU can be any combination of letters and numbers, and is often structured to reflect key attributes like category, color, or size.

For example, a SKU like “TSH-NAV-M” might refer to a navy blue t-shirt in size medium. These codes are unique within a store but not standardized across other businesses.

The WebshopAssist SKU Generator App helps create consistent, readable SKUs for every product and variant, saving time and reducing errors across operations.

What Is a UPC?

A UPC, or Universal Product Code, is a standardized barcode used across global retail. UPCs are typically 12 digits long and registered through organizations like GS1. Unlike SKUs, UPCs are meant for external use—especially when selling through large retailers, online marketplaces, or physical stores that require global product identification.

Most UPCs are used in barcode form for scanning at the point of sale. They are fixed identifiers, which means you cannot customize them the way you can with SKUs.

Should You Use Both a SKU and a UPC?

In most retail environments, the answer is yes. You should use both.

Use a SKU for internal tracking, warehouse operations, and label printing.
Use a UPC for compliance with retailers, marketplaces, and POS scanning.

Having both allows your store to operate efficiently while also meeting external requirements. For example, you can use the SKU to generate internal reports, pick orders, and organize products. At the same time, the UPC ensures your product is recognized in global retail systems.

Do Variants Need Their Own SKUs and UPCs?

Yes. Each variant—such as a different size or color—should have a unique SKU and its own barcode. This allows for accurate inventory tracking and avoids fulfillment errors.

With the WebshopAssist SKUGen, you can generate a distinct SKU and barcode for every product variant, then export them for use in Shopify or bulk label printing tools.

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Want to learn more?

Below are expert guides on key topics every Shopify merchant should understand