Card sorting: how it works, which sort to run, and what to do with the results
By UXbeam · Information architecture tools since 2021 · Published September 20, 2026
Card sorting asks people to group your content and name the groups. It shows how participants would group the content, rather than forcing them into the structure your team already uses. This guide covers the method: sort types, cards, participants, analysis, and what to do with a result. Want to run one? Open the free card sorting tool.
What a card sort measures, and what it does not
A sort produces two kinds of evidence. Grouping: which cards people put together, and how consistently. Naming: what they call the groups, in their own words. Grouping tells you about structure; naming gives you evidence about the labels participants naturally reach for.
A sort does not measure findability. Participants see every card and every group at once; in the product, someone sees one level of labels and has to guess. Agreement in a sort is a good sign for a structure and no guarantee of it. That question belongs to tree testing, and the two methods are designed to run in sequence.
- You provide
- 15 to 60 cards, one concept each, with an optional one-line description. For closed and hybrid sorts, a list of categories.
- The participant does
- Drags cards into groups in a browser. No account, no install. In an open sort they name the groups; in a closed sort they use yours; in a hybrid sort, both.
- You get
- Every individual sort, a similarity dendrogram, a similarity matrix, the category labels people wrote, the cards that never settled, and the distinct organization patterns when participants disagree.
When to run one
No structure yet
You have an inventory of features or content and no agreed way to group it. An open sort gives you a first structure that comes from users rather than from a workshop.
Restructuring or migrating
The current sections have grown by accretion. A sort shows which of them still make sense to users and which exist only because of history.
A label dispute
Two teams want two names for the same section. The category names participants write settle it with evidence instead of seniority.
Two plausible structures
Organize by product area or by task? By department or by life event? A sort shows which rule your participants reach for, and whether they all reach for the same one.
Open, closed and hybrid sorts
The three sort types differ in one setting, who supplies the categories, and that changes the question the study can answer, the instruction participants see, and how to read the result.
| Open | Closed | Hybrid | |
|---|---|---|---|
| Categories | Participants create and name them | You supply them; participants use only those | You supply them; participants may add their own |
| Question answered | How do people organize this content, and what do they call the groups? | Do the cards fit the categories we have? | Do our categories cover the content, and what is missing? |
| Best when | There is no structure yet, or you suspect the current one | You have a set of sections and want to check placement | You have most of a structure and suspect a gap |
| What participants read | Sort the items into as many categories as needed | Sort each item into one of the categories below | Sort each item into a category below, or add a new one if needed |
| Pattern summary in UXbeam | Mental models | Category-use patterns | Organization patterns |
| Guide | Below | Closed card sorting | Hybrid card sorting |
The pattern summaries are named differently on purpose. A closed sort constrains what participants can express, so a coherent difference between two groups is usually two readings of your labels, not two mental models of the domain.
Open card sorting
An open sort gives participants the most room to surprise you. Participants get the cards and nothing else: they decide how many groups to make, what goes in each, and what to call them. The result reflects the organizing rule they actually reach for, by topic, by task, by who it is for, by where it happens. That organizing rule can change the entire structure that follows, and a closed sort cannot reveal it because you have already supplied the categories.
Read the labels first. Participants' category names show the language they reached for while organizing the material. Two groups can produce the same groupings under different names, or different groupings under the same name; both matter, and only an open sort shows either.
Watch for participants who make one group per card, or one group for everything; UXbeam shows every individual sort so you can exclude them. Cards that land somewhere different for every participant are ambiguous, and the fix is usually a rewrite or a description, not a new section. And when the groupings split into coherent patterns, resist averaging them; the next sections cover why.
Writing the cards
One concept per card, 15 to 60 cards
UXbeam accepts 15 to 60. Larger sets increase participant effort, so sample a very large inventory or split it into focused studies.
Write in the user's language
Order tracking, not OMS status view. If a card needs explaining, add a description after
||; participants can reveal it, and UXbeam reports how often they did, which flags unclear card names.Keep category words out of card names
Billing settings answers the question for the participant. Name the thing and let people decide where it lives.
One level of granularity
Unless you want a hierarchy back. Mixing top-level topics with tiny features produces one.
Randomize the order
Cards, and in closed and hybrid sorts, categories too. Otherwise the first items seen anchor everyone's groups.
How many participants
There is no universal number; the practical test is stability. Run until the groupings stop moving as new sorts arrive. A study in the teens usually shows which cards are ambiguous and which groups are obvious. Deciding between two competing structures, or trusting a minority pattern, asks for more, because those results move as the sample grows: in the government services sort, the smaller action-based pattern was reported at 69 responses and had been absorbed by 82.
Recruitment is yours. UXbeam gives you a study link for your own users, customers or a panel you already work with. Participants need no account, and responses are not capped.
Reading the results
UXbeam builds the analysis from your results as they arrive:
- Similarity dendrogram with an adjustable grouping threshold: the combined structure across all participants. Cards often sorted together sit close.
- Similarity matrix. How often any two cards shared a group, for checking a specific pair.
- Category labels. The names participants wrote, with counts; in closed and hybrid sorts, how your categories were used and what was added.
- Stable groups, ambiguous cards and outliers. What holds across thresholds, what jumps, what never settled.
- Every individual sort, to read one participant's logic or exclude a careless one.
Read the dendrogram in two passes. Find a threshold that gives a useful number of top-level groups and look at what each group holds. Then move the threshold and watch which cards move. A card that stays put has a stable relationship to that group. One that moves as the threshold changes is worth inspecting: it may plausibly belong with more than one group, or its wording may be ambiguous.
Mental Model Detection
Mental Model Detection looks for recurring differences in how participants organize the same cards. When distinct patterns appear, UXbeam keeps them separate rather than averaging everyone into one structure.
Participant card sorts only. Participants who organize the cards similarly contribute to the same pattern; no profile or demographic information is used.
UXbeam compares participant sorting patterns and looks for coherent groups. Very small or weak patterns are treated cautiously rather than presented as meaningful alternatives.
Patterns depend on who participated and can change as responses arrive or participants are excluded. An early pattern is a hypothesis, not a stable segment.
A pattern describes how people in this study sorted these cards. It is not evidence of a permanent psychological or audience segment.
Participant patterns, the overall item dendrogram, and candidate structures are different views of the data. One does not substitute for another.
UXbeam uses "mental models" for open sorts. Closed sorts report category-use patterns and hybrid sorts report organization patterns because supplied categories constrain what participants can express.
Synthetic pretest output is kept separate from participant evidence and is not used to create participant patterns.
When more than one pattern appears, you can open each as a separate candidate sitemap and test the alternatives rather than averaging them together.
From grouping to sitemap to tree test
- Pick a groupingThe dendrogram at a threshold, or one detected pattern.
- Sitemap +Opens it as an editable sitemap, pre-populated. Rename, merge, move.
- Save a versionThe structure you intend to ship, kept apart from the sort data.
- Tree Test thisThe sitemap opens as a tree test. Write tasks, share the link.
- Read task successWhere people went, where they gave up, which labels misled.
If the goal is findability, follow the sort with a tree test. A sort shows that people agree where a card belongs when they can see all the options; a tree test shows whether they can find it when they cannot. A tree test measures the gap between those two conditions. See the tree testing guide, and the examples for a sort carried through to a two-structure tree test.
In this guide
Closed card sorting
Predefined categories. When to use it, how to read placement agreement, and why agreement alone does not validate navigation.
Hybrid card sorting
Your categories plus the ones participants add. How supplied categories constrain the result, and how to interpret what people create.
Card sort templates
Three card sets with categories and instructions, in the exact format the UXbeam setup page accepts. Copy, paste, launch.
Card sorting examples
Real sorts: the cards, the groupings that emerged, the category decisions, and the tree test or workshop that followed.
See also: Organizing principles in information architecture · Tree testing vs card sorting · The UXbeam card sorting tool
Frequently asked questions
Open or closed first?
Open, unless you already have categories you are committed to. An open sort tells you the organizing rule and the vocabulary; a closed sort assumes both. Running closed first is how teams validate a structure that nobody would have proposed.
Can participants do it remotely, on their own?
Yes. A UXbeam card sort is unmoderated: you share a link, participants sort in their browser without an account, and results appear as they finish. Sorting needs a laptop or desktop screen; a participant who opens the link on a phone is asked to reopen it on a larger screen.
What is the difference between a card sort and a tree test?
A card sort discovers how people would group and name things when they can see everything. A tree test checks whether people can find one thing in a finished structure, seeing one level at a time. Sort first, then test; the comparison article goes into detail.
Does UXbeam recruit participants for card sorts?
No. Card sorting in UXbeam is run with your own participants through a shared link. There is no cap on the number of participants or responses.