IA
Open Card Sorting
A practical information architecture method for uncovering how users group content and what language they use to describe it.
How to use open card sorting to understand user mental models, shape information architecture, and build navigation around the language people naturally use.
Quick take
If you want to understand how users naturally group and label information, use open card sorting.
Related Services
What it is
Open card sorting is a UX serviceUser ResearchUnderstand user behaviour, validate ideas, and make clearer product decisions with evidence you can act on.Open service method used to explore how users organise information in a way that makes sense to them.
Participants are given a set of items, usually pieces of content or glossaryFeatureA feature is a specific piece of functionality within a product that delivers value to users. It represents something users can do or experience as part of the overall product.Open glossary term, and asked to group them into categories. They then create their own labels for those groups.
Unlike guideClosed Card SortingTesting whether predefined categories and labels make sense to users so structure and navigation can be validated.Open guide, where categories are predefined, open card sorting allows users to define both the structure and the language.
The goal is to uncover natural glossaryMental ModelA mental model is the way users understand how a system works based on their past experiences and expectations. It shapes how they predict interactions and outcomes.Open glossary term and inform serviceInformation ArchitectureImprove navigation, content structure, and findability so users can understand where things are and how to move through them.Open service.
Open card sorting is most useful when you need to understand how users think the content should be grouped, before you impose a structure of your own.
When to use it
Use this method when you are defining or restructuring content.
It is most useful when:
It is less useful when:
Open card sorting is often used alongside closed card sorting and tree testing.
Key takeaway
Use open card sorting when the main question is how content should be grouped and named from the user perspective, not whether an existing structure already works.
How to run it
Set up properly.
Before you start, be clear on what items will be included, how many items users will sort, and what you want to learn.
Keep the number of items manageable to avoid overload.
Run the method.
Open card sorting is exploratory and flexible.
Give users a set of items. Ask them to group items in a way that makes sense. Ask them to label each group. Observe how they organise and think. Capture reasoning and glossaryPatternA reusable solution to a common design problem.Open glossary term.
Encourage users to think naturally, not logically.
Capture and make sense of it.
The value comes from glossaryPatternA reusable solution to a common design problem.Open glossary term in grouping.
Look across results to identify common groupings of items, glossaryPatternA reusable solution to a common design problem.Open glossary term in labels and terminology, differences between users, and areas of confusion or inconsistency.
Use this to inform structure and naming.
What to look for
Focus on:
Where it goes wrong
Most issues come from:
If users are confused, the results will be too.
What you get from it
Done properly, this method gives you:
Key takeaway
It helps you structure content the way users expect.
Get in touch
If this sounds like something you need, we can help you structure your content in a way that makes sense to your users.
No guesswork. No assumptions. Just glossaryClarityClarity is how easily users can understand what is happening and what they need to do.Open glossary term you can glossaryBuildA build is the process of compiling and packaging code into a runnable application.Open glossary term on.
FAQ
Common questions
A few practical answers to the questions that usually come up around this method.
What is open card sorting in UX?
It is a method where users group content and create their own category labels.
When should you use open card sorting?
Use it when defining serviceInformation ArchitectureImprove navigation, content structure, and findability so users can understand where things are and how to move through them.Open service or glossaryNavigationHow users move around a website or product.Open glossary term.
How many items should you include?
Typically 30 to 60 items, depending on complexity.
How many participants do you need?
Usually 15 to 30 to identify clear glossaryPatternA reusable solution to a common design problem.Open glossary term.
Does open card sorting improve UX?
Yes. It ensures your structure matches how users think.