IA

Closed Card Sorting

A practical information architecture method for validating predefined categories and checking whether users place content where you expect.

How to use closed card sorting to validate information architecture, refine category labels, and test whether your structure aligns with user expectations.

16 June 20204 min read

Quick take

If you want to test whether your existing structure makes sense to users, use closed card sorting.

What it is

Closed card sorting is a UX method used to evaluate how well predefined categories and structures work for users.

Participants are given a set of items and a fixed set of categories. Their task is to place each item into the category they think it belongs in.

Unlike , where users create their own groups, closed card sorting tests an existing or proposed structure.

The goal is to validate , , and .

Closed card sorting is most useful when you already have a structure in mind and need to know whether it actually makes sense to users.

When to use it

Use this method when you already have a structure to test.

It is most useful when:

You want to validate an existing information architecture
You are testing navigation or menu structures
You need to refine category labels
You are preparing for launch or redesign
You want to reduce findability issues

It is less useful when:

You need to explore how users naturally group content
The structure is not yet defined
You need behavioural or interaction insight
Closed card sorting is often used after open card sorting and before tree testing.

Key takeaway

Use closed card sorting when the main question is whether your current or proposed structure works, not what the structure should be from scratch.

How to run it

Set up properly.

Before you start, be clear on what categories users will sort into, what items will be included, and what success looks like.

Ensure categories are clearly defined and meaningful.

Run the method.

Closed card sorting is structured and evaluative.

Provide users with predefined categories. Give them a set of items to sort. Ask them to place each item into a category. Capture where items are placed. Optionally capture reasoning.

Keep instructions clear and unbiased.

Capture and make sense of it.

The value comes from measuring .

Look across results to identify where users agree or disagree, items that are consistently misplaced, confusing or unclear categories, and in .

Use this to refine structure and labels.

What to look for

Focus on:

Agreement rates
How consistently items are placed
Misclassification
Items placed in the wrong category
Label clarity
Whether categories make sense
Ambiguity
Items that could fit in multiple places
Patterns
Trends across users

Where it goes wrong

Most issues come from:

If categories are unclear, results will be too.

poorly defined categories
ambiguous or unclear items
forcing items into unsuitable categories
ignoring user reasoning
over-relying on quantitative results

What you get from it

Done properly, this method gives you:

validation of your information architecture
insight into category clarity
improved navigation and structure
reduced findability issues

Key takeaway

It helps you ensure your structure works for real users.

Get in touch

If this sounds like something you need, we can help you validate and refine your structure so users can find what they need quickly.

No guesswork. No assumptions. Just structure that works.

FAQ

Common questions

A few practical answers to the questions that usually come up around this method.

What is closed card sorting in UX?

It is a method where users sort items into predefined categories.

When should you use closed card sorting?

Use it when validating an existing structure or .

How is it different from open card sorting?

explores user-defined structure, while closed card sorting tests a predefined one.

How many participants do you need?

Typically 15 to 30 to identify clear .

Does closed card sorting improve UX?

Yes. It helps ensure your structure aligns with user expectations.

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Previous feedback

Will Parkhouse

Senior Content Designer

01/20