How can you distinguish between two almost identical products in your catalog? How can you automate your stock management without spending nights on it? The answer lies in three letters: SKU. An acronym for Stock Keeping Unit, this unique code identifies each product unit precisely. For e-tailers, it’s much more than a simple identifier: it’s a real lever for logistics and sales performance.
- What is a SKU (Stock Keeping Unit) and what is it used for?
- The 4 major advantages of a good SKU system for your e-commerce business
- How to create your SKU codes: best practices to follow
- The SKU: the core element of the OMS Shippingbo system
In this article, you’ll discover what a SKU is, how to create it efficiently, how it differs from other product codes (EAN, UPC, serial numbers…) and why it’s essential for inventory management in an omnichannel environment. We’ll also look at how Shippingbo integrates the SKU at the heart of its OMS to help you centralize your logistics operations.
What is a SKU (Stock Keeping Unit) and what is it used for?
The Stock Keeping Unit (SKU ) is a unique reference assigned to each distinct product unit. It enables products to be differentiated according to their characteristics (size, color, model, etc.), and to be efficiently managed in a logistics or sales information system.
Used everywhere, from the smallest warehouse to the largest online retailer, the SKU code has become an essential tool for e-tailers. It is used not only to identify a product, but also to track inventory, optimize logistics flows and make strategic decisions based on accurate data.
SKU code definition, characteristics and structure
A SKU code is an internal alphanumeric combination, freely created by a company to uniquely identify a specific product in its catalog. It differs from standardized codes such as GTIN (Global Trade Item Number),ISBN, or EAN/UPC barcodes, in that it does not follow any universal standard.
Designed primarily for internal use, the SKU enables each product to be tracked, stored and analyzed according to its specific characteristics. For example, a code such as TSH-BLU-L may designate a blue t-shirt in size L. This makes it easier to sort, search and organize the product catalog in logistics information systems.
Common confusion: SKU vs. UPC, EAN and barcodes
It’s common to confuse SKU and UPC, or SKU and EAN, because these different codes can coexist on the same product. Yet their functions, structures and uses are quite distinct.
- The SKU (Stock Keeping Unit) is an internal code freely created by the merchant or logistician. It is designed to meet specific operational needs: stock management, picking, packing, sales tracking, etc. It’s a personalized and adaptable code, which reflects the product’s characteristics according to each company’s own logic (category, size, color, supplier, etc.).
- Both the UPC (Universal Product Code) and theEAN-13 (European Article Number) are universal identifiers. They are standardized, assigned by official bodies (such as GS1) and designed to be scanned by barcode readers at physical or virtual points of sale. These codes enable the same product to be recognized anywhere in the world, regardless of the retailer.
- In practice, the SKU can be linked to a barcode to make it easier to read in the warehouse, but it remains above all a SKU inventory management tool. It is used in software applications such as ERP, a WMS or an OMSto manage logistics, stocks and orders internally.
In a nutshell:
- The SKU is designed to manage your internal operations,
- TheEAN/UPC is designed to identify a product universally across all sales channels.
It’s the use that differentiates these codes: SKU for internal management (logistics, inventory, reporting), UPC and EAN for external marketing (marketplaces, stores, distribution).
The 4 major advantages of a good SKU system for your e-commerce business
In a context where logistics flows are intensifying and becoming more complex, the implementation of structured SKU management is becoming a differentiating factor. In fact, according to the latest 2024 logistics predictions published by Inbound Logistics, digitalization, real-time visibility and centralized operations are among the strategic priorities for companies wishing to remain competitive (Inbound Logistics, 2024).
A well-structured Stock Keeping Unit (SKU ) system does more than just name your products: it becomes a real performance lever for your e-commerce business. From inventory to delivery, product distribution and analysis, here are the 4 key benefits you can derive from a good SKU-based management system.
Accurate inventory and real-time tracking (unified inventory)
An inventory management system provides a precise and instantaneous view of your available quantities. Each SKU becomes an autonomous unit of analysis, essential for calculating safety stock, avoiding out-of-stocks, and balancing stocks between warehouses.
With a solution like Shippingbo, the SKU is used to centralize information and synchronize stock data in real time across all your sales channels, enabling unified, automated management.
Simplify picking and reduce logistical errors
Good picking and packing speeds up warehouse operations. The operator scans the SKU to check that the right item has been picked. This greatly reduces errors, improves customer satisfaction and optimizes storage space per SKU.
With a connected WMS like Shippingbo’s, SKUs are linked to warehouse locations, enabling smooth organization of picking sessions, notably via PDA or pick-to-light.
Improve sales forecasting and profitability
Each SKU profitability analysis enables you to identify which products are performing well (and which aren’t). This is key data for adjusting your assortments, prices or marketing actions.
By tracking sales history by SKU, you can plan your supplies more effectively and avoid overstocking or understocking.
Facilitate the distribution of your products in omnichannel and on marketplaces
In a context of multi-channel SKU management, a unique code is essential for synchronizing product data sheets on Shopify, Amazon, Cdiscount or any other platform.
With Shippingbo, every SKU for the marketplace is uniformly referenced, facilitating order management, flow automation and unified stock control. unified inventory.
How to create your SKU codes: best practices to follow
Creating a SKU is not an easy task. A poorly thought-out nomenclature can quickly become a headache, especially as your catalog expands. To ensure smooth, scalable management, here are the basic principles you need to follow to structure your SKU codes efficiently and sustainably.
Define a logical structure (Category, Attributes, Supplier)
Developing a clear, consistent and legible SKU coding structure is a crucial step in guaranteeing the scalability of your product catalog. As your product range grows, a rigorous code architecture becomes essential to avoid duplication, picking errors or confusion during dispatch.
Your SKU must include several key segments, which reflect the product’s essential characteristics. Each segment represents useful information, readable by your teams, your internal tools(ERP, WMS, OMS) and your external partners (suppliers, marketplaces, carriers, etc.).
Here are the main elements to include:
- Product category: used to group similar items together. For example: TSH for t-shirt, PNT for pants, SAC for backpack. This helps to filter and sort references more easily, particularly during a search or logistics audit.
- SKU attributes: these reflect the specific features of the product variant. Color, size, material, cut, or any other discriminating characteristic can be integrated. Example: BLACK for color, 38 for size.
- Supplier item code or internal reference: this part can reflect a supplier-specific identifier or a reference you’ve defined for your management. This facilitates the link with supplier orders, after-sales service or supply flows.
Example:
PNT-NOIR-38-ZARA: this SKU corresponds to a pair of pants (PNT), black, size 38, from the brand or supplier Zara.
Each segment is separated by a hyphen (-) for easier reading. This type of structure makes the SKU :
- understandable by humans, which helps warehouse operators ;
- easily exploited by the machine, whether for SKU / EAN mapping, identification in a WMS, or multi-channel distribution on marketplaces.
In short, a well-structured SKU is a common language between your catalog, your digital tools and your logistics partners. It plays a key role in the fluidity of your operational chain.
Errors to avoid when creating SKUs (length, characters, ambiguous numbers)
Creating a functional SKU is more than just assembling a few random letters and numbers. Incorrect coding can lead to picking errors, tool conflicts or identification problems in the marketplace. Here are the best practices for designing SKUs that are legible, robust and durable:
- Avoid ambiguous characters: some characters are visually too close, such as O and 0, or I and 1. They can be misread by an operator or misinterpreted by an automated system. Use clearly distinguishable letters and numbers.
- Optimum length: SKUs that are too long are difficult to read, print or scan. An ideal length is between 10 and 14 characters. This is sufficient to integrate the product’s essential attributes without weighing down the structure.
- Use standard separators: the hyphen (-) is the most commonly used to separate blocks of information. It improves human readability and is compatible with most systems (ERP, WMS, marketplaces…).
- Avoid special characters and spaces: @, &, /, + or spaces can cause problems for some software or be misinterpreted when exporting data. Keep it simple and standard.
- Ensure SKU uniqueness: each product (including size, color and model variants) must have a unique item code. Duplicates can distort your inventory, disrupt your exports or create order errors.
Finally, it can be useful to use an online SKU generator to quickly structure a product catalog. However, these tools offer standard templates that often need to be adapted to your internal logic, tools and business constraints.
The SKU: the core element of the OMS Shippingbo system
At Shippingbo, the SKU is not just used to identify a product. It is the single point of reference on which all logistics operations are based, from order to shipment. Thanks to OMS, Shippingbo transforms the SKU into a strategic pivot, facilitating omnichannel management, stock synchronization and flow automation.
Here’s how this apparently simple code becomes one of the pillars of logistics performance.
OMS Shippingbo for omnichannel orchestration by SKU
Shippingbo’s OMS module is based on the SKU as the single anchor point for controlling the entire order cycle. Every operation, from picking to shipping, is structured around this reference. In particular, it enables :
- Centralize multi-channel orders, by grouping all flows (e-commerce site, marketplaces, points of sale) in a unified interface.
- Real-time SKU stock tracking, avoiding out-of-stocks and overselling errors.
- Intelligent order routing, according to customer region, stock availability or sales channel priority.
Thanks to this system, your flows are automatically orchestrated from a single product identifier. The result: greater fluidity, fewer errors and real operational time savings.
Linking the SKU to the warehouse: OMS + WMS integration for perfect execution
Synchronization between OMS and Shippingbo’s WMS enables each SKU to be associated with a precise storage location in the warehouse. The SKU then becomes the operational key: it guides order picking, stock level checks and product returns management.
Whatever the sales channel – e-commerce site, marketplace or physical store – logistics processing remains uniform. The same SKU will trigger the same execution rules, guaranteeing consistent, fluid and frictionless omnichannel logistics.
SKUs as the basis for supply chain KPI analysis
Tracking your performance indicators is based on rigorous management of rotating inventories by SKU, backed up by regular audits and detailed flow analysis.
By structuring your data around the SKU, you can easily answer key questions: Which products are the most profitable? Which products generate returns or overstocks? How long does it take from order to delivery?
These KPI become truly exploitable when the SKU serves as a single reference for all your supply chain reporting. This is the prerequisite for precise management of your business, and for optimizing your logistics and sales decisions.
This logic is in line with the product rationalization recommendations issued by Unleashed Software in 2024, which stress the value of analyzing the profitability of each SKU to improve overall supply chain performance (Unleashed Software, 2024).
The SKU, a discreet but essential driver of your e-commerce efficiency
In an increasingly demanding e-commerce environment, where every second counts and every logistical error can be costly, the SKU has become a strategic pillar. This simple code, if well structured and used, becomes a cross-functional management tool: it helps you organize your catalog, make your stocks more reliable, streamline your shipments and sell better across all your channels.
A well thought-out SKU means fewer errors, less friction and greater performance. It harmonizes data between your teams, your software, your warehouses and your sales channels. It’s also essential for anticipating demand, tracking your logistics KPIs, and orchestrating truly omnichannel logistics.
And to take full advantage of this power, you need to equip it intelligently. With Shippingbo, your SKUs become the driving force behind a centralized, automated and connected logistics system, freeing you from manual tasks and giving you greater agility.
With Shippingbo, turn your SKUs into a real growth lever.
👉 Want to switch to an intelligent, connected management system? Find out how Shippingbo can boost your logistics today!
Stock Keeping Unit FAQs
The SKU is an internal alphanumeric code, created by the company for its own inventory management and product variants. The barcode (EAN/UPC) is a universal numerical code used for international trade and checkout.
The number of SKUs is the product of the total number of all unique variations of a product. Example: 3 colors × 4 sizes × 2 materials = 24 different SKUs.
The SKU is the only reliable product identifier that enables software (such as OMS) to synchronize and count the precise stock of a variant across all sales channels (e-commerce, marketplaces, boutiques) in real time.
An ideal SKU is concise (8 to 12 characters), uses logical abbreviations and follows a consistent order (e.g. Category-Color-Size) to be readable and interpretable by both humans and computer systems.
Glossary
SKU (Stock Keeping Unit)
Unique internal code identifying a stock unit, including its variants (size, color, model).
EAN (European Article Number)
Bar code standardized in Europe, used to scan products at the checkout.
UPC (Universal Product Code)
Bar code used mainly in North America, equivalent to the EAN.
OMS (Order Management System)
Order management system that centralizes, orchestrates and synchronizes order flows.
WMS (Warehouse Management System)
Warehouse management software for tracking stock movements and optimizing picking.
GTIN (Global Trade Item Number)
International product identification number, used for standardized commercial exchange.
BBD / UBD
Use-by date / Best-before date, often integrated into the SKU in the food sector.
Mapping SKU / EAN
Correspondence between an internal identifier (SKU) and an external identifier (EAN/UPC) to facilitate multi-channel integration.
Rotating inventory
The technique of checking inventory on a rolling basis, rather than during a complete annual stocktaking.