Alphanumeric formats: SKUs made up of letters only can be misread as part of the product description. Numeric SKUs can be confused with other numeric codes such as the EAN's. Alphanumeric SKU's can be easily identified.

More than six characters: If you have limited inventory, you might be tempted to use short, 4-5 character-long SKUs. However, short SKUs limit your ability to expand inventory later. Something longer than 6-8 characters gives you enough room to include all the necessary information.

Use 1-3 characters for each attribute: An SKU is meant to relay key product attributes succinctly. As such, compressing every attribute to 1-3 characters is a good practice. You can use the first 1-3 characters (such as ‘F’ for ‘Female’), create an acronym for longer terms (such as ‘RJ’ for ‘rain jacket’), or use some intelligible abbreviation (such as ‘BWN’ for ‘brown’).

Never use spaces: SKUs are meant to be read by a computer and many software tools struggle to understand spaces. If you absolutely must use a space in your SKU, use a hyphen (-) or underscore (_) instead.

Avoid special characters: While you can technically use special characters (such as “/@$%^#”) in your SKUs, they can confuse users. The ‘@’ character, for instance, can be misread as an email address, while the ‘/’ character can be read as a date. Try to use only letters and numbers to get the the best results.

Avoid confusing numbers & letters: The number ‘0’ and the letter ‘O’ can be difficult to make out on some fonts. Similarly, letters such as ‘I’, ‘L’ and the number ‘1’ can be unintelligible at times. If possible, avoid using these letters.

Always use uppercase letters: Most of the legibility issues with the letters ‘I’, ‘L’, and ‘O’ can be solved simply by using uppercase letters. As best practice, always use uppercase only in your SKUs and avoid mixing lowercase and uppercase letters.

Valid SKU's format examples

Bad SKU's format examples