What is a SKU?
A SKU, short for stock keeping unit, is an identifier a retailer or brand assigns to each distinct item it stocks, so every variant can be counted, sold and reordered on its own. In fashion one style usually breaks into many SKUs, one per color and size combination, which is how a SKU differs from a style number or from a barcode such as a GTIN.
SKUs are internal. Each business makes up its own, so the same product carries different SKUs at the brand and at each retailer that stocks it.
How SKUs are structured in fashion
Fashion SKUs are usually built from three layers:
- Style: the design, for example one T-shirt pattern
- Colorway: each color the style comes in
- Size: each size of each color
A readable SKU often combines them, such as TEE01-NVY-M for a navy T-shirt in medium. Meaningful codes help people in the warehouse; purely numeric codes avoid problems when names change. Either works if the system is consistent.
SKU, style number and barcode
- A style number identifies the design across all colors and sizes. It is what designers and buyers talk about.
- A SKU identifies one sellable variant inside the business.
- A GTIN, printed as a barcode (UPC or EAN), identifies the same variant across the whole supply chain and is issued through GS1. Marketplaces and retailers often ask for it.
Why SKUs matter for product photography
Photography is planned on a mix of these levels. Sizes rarely need their own images, but colorways do, because the shopper picks a color and expects to see it. In practice, image requirements are counted per style and colorway, and image files are named after the SKU or style-color code so the shop system can match them automatically.
That makes the SKU list the starting point of every shot list. It shows which products need images, which colorways are missing, and which new SKUs are coming before the samples arrive.
What drives the cost and time
The number of SKUs is one of the main drivers of image cost. Each new colorway adds a gallery, and each gallery needs a sample, studio time and retouching. Fast-moving ranges with many small drops multiply the work, and colorways that sell in low numbers often end up with a single image or none, because shooting them is hard to justify.
SKUs with AI, and the NotShot approach
AI product imagery changes the cost per SKU rather than the SKU logic. When a colorway can be rendered instead of shot, low-volume colors can get the same gallery as the bestseller. The checks remain per SKU: each image must show the right color and details for the variant it is attached to.
NotShot is a Berlin-based tool for on-model product photography without the photoshoot. Every render is judged against your upload. If a render fails the check, you get your credits back. For how image costs add up across a catalog, read what catalog photography actually costs a small DTC fashion brand.
Related terms
- Colorway: one color version of a style, the level photos are planned at
- PDP: the product page where SKUs appear as variants
- Shot list: the image plan that starts from the SKU list
- Catalog photography: product-by-product images across a range
- DTC: brands that sell straight to their customers
- Return rate: the share of orders that come back
- What a fashion photoshoot costs, and the alternative
Questions we get asked
- What does SKU stand for?
- SKU stands for stock keeping unit. It is the internal code a business gives each distinct item it stocks.
- Is a SKU the same as a barcode?
- No. A SKU is internal and chosen by each business. A barcode carries a GTIN (UPC or EAN), which is issued through GS1 and identifies the same item across every company that handles it.
- Does every size need its own SKU?
- Yes, if sizes are stocked and sold separately, which is almost always the case in fashion. That is why one style can have many SKUs.
- Does every SKU need its own photos?
- Not every size, but every colorway should have its own images, because the shopper picks a color and expects to see it. Sizes usually share the images of their colorway.
- How should I name product image files?
- Use the SKU or the style and color code plus the view, for example the code followed by front, back or detail. Consistent names let the shop system match images to variants automatically.