Card Sorting

Card sorting is a UX research method used to understand how people naturally group and label information. Participants receive a set of cards, each representing a piece of content or functionality, and organize them into categories that make sense to them. The result reveals users' mental models and directly informs information architecture decisions: navigation structure, menu labels, and page hierarchy.

There are two main variants. In an open card sort, participants create and name their own categories, which is ideal early in a project when the structure is still undefined. In a closed card sort, participants place cards into predefined categories, which works well for validating an existing structure. Running a card sort before designing navigation significantly reduces the risk of building a structure that makes sense internally but confuses real users.