What is Card Sorting?
Card sorting is a user experience research methodology used to discover how people understand and categorize information. Participants organize topics or content items into groups that make sense to them, and may also label these groups. This technique reveals users' mental models and helps designers create information architectures that align with user expectations.
Originally conducted with physical index cards on a table, card sorting has evolved into a sophisticated digital research method. Online card sorting tools now enable remote, unmoderated studies with participants worldwide, making it easier and more cost-effective to gather insights from your target audience.
Types of Card Sorting
folder_open Open Card Sort
Participants create and name their own categories. Best for discovering how users naturally group content and what terminology they use.
folder Closed Card Sort
Participants sort cards into pre-defined categories. Ideal for validating an existing structure or testing category labels.
folder_special Hybrid Card Sort
Combines both approaches: pre-defined categories with the option to create new ones. Useful when you have a partial structure but want flexibility.
Why Do Card Sorting At All?
Card sorting is a valuable technique for UX research that provides concrete benefits for both your team and your users:
sentiment_satisfied Enhanced User Experience
Card sorting helps you organize content and navigation in a way that resonates with your target audience, ultimately improving user satisfaction and reducing frustration.
account_tree Efficient Information Architecture
It aids in designing intuitive site structures and hierarchies, making it easier for users to find what they need and reducing support queries.
analytics Data-Driven Decisions
Card sorting generates quantifiable data and user feedback, enabling evidence-based design decisions rather than relying on assumptions or opinions.
payments Cost-Effective Research
Compared to other research methods, card sorting is a cost-effective way to gather valuable insights from your users, especially with online tools.
The Card Sorting Process
Conducting an effective card sorting study involves several key steps. Whether you're using online tools or physical cards, following this process ensures reliable, actionable results:
1. Define Your Research Goals
Start by identifying what you want to learn from the card sort. Are you organizing a new website structure, validating existing categories, or discovering user mental models? Clear objectives guide all subsequent decisions.
2. Choose Your Card Sort Type
Select between open, closed, or hybrid card sorting based on your research objectives and what you already know about your content structure. Open sorts provide more discovery, while closed sorts offer validation.
3. Prepare Your Cards
Create cards representing your content items. Use clear, concise labels that users will understand without additional context. Typically 30-60 cards works well—fewer than 30 may not provide enough complexity, while more than 60 can be overwhelming. Include card descriptions or tooltips for complex topics.
4. Recruit Participants
Recruit 15-30 participants who represent your target audience. Research shows that 15 participants typically reveal most patterns, while 30+ provides stronger statistical confidence. Ensure participants understand your product domain but aren't experts who may sort differently than typical users.
5. Conduct the Study
Have participants sort cards into groups that make sense to them. For open sorts, ask them to name the groups they create using terms they would naturally use. Consider having participants think aloud or add comments to capture their reasoning.
6. Analyze Results
Use dendrograms, similarity matrices, and category analysis to identify patterns. Look for consensus on groupings, commonly used category names, and cards that participants consistently disagreed about. Online tools typically provide automated analysis features.
7. Apply Insights to Your Design
Use the findings to inform your information architecture, navigation design, or content organization decisions. Create sitemaps, taxonomies, or navigation structures based on how users naturally group your content.
Return on Investment: The Business Case for Card Sorting
trending_up Measurable Business Impact
Card sorting delivers tangible ROI through improved user outcomes and reduced business costs:
- Increased Findability: Users can locate information faster, reducing task completion time by 20-40%
- Reduced Support Costs: Better navigation means fewer support tickets and customer service calls
- Higher Conversion Rates: When users can find what they need, conversion rates improve significantly
- Decreased Bounce Rates: Intuitive organization keeps users engaged longer
- Faster Development: Evidence-based design reduces endless debates and costly redesigns
- Competitive Advantage: User-centered architecture differentiates your product from competitors
A typical card sorting study costs between $500-$5,000 depending on participant recruitment and tool selection. However, the cost of poor information architecture—measured in lost conversions, increased support costs, and user frustration—far exceeds this investment. Organizations that invest in upfront UX research, including card sorting, see 10:1 to 100:1 ROI through reduced development rework and improved user outcomes.
What UX Experts Say About Card Sorting
"Card sorting is one of the most useful techniques for understanding how users think about content and functionality. It's essential for creating information architectures that work the way users expect."
"The value of card sorting lies in its ability to reveal the mental models of your users. When you organize information based on how users think, navigation becomes intuitive rather than confusing."
"Card sorting helps you get out of your own head. Designers often organize things based on how the business is structured, but users don't care about your org chart—they care about completing their tasks efficiently."
"When designing information architecture, the most important thing is to understand your users' expectations. Card sorting gives you direct insight into their mental models, reducing guesswork and assumptions."
"Card sorting is particularly valuable early in the design process when you're establishing the foundational structure. Getting the information architecture right from the start prevents costly redesigns later."
Ready to Start Card Sorting?
Now that you understand the value and process of card sorting, you're ready to choose the right tool for your research needs. Our comprehensive tools comparison page evaluates the leading online card sorting platforms across dozens of dimensions including features, pricing, and capabilities.
Have questions about card sorting methodology or best practices? Check out our FAQ section for answers to common questions. Looking to dive deeper into information architecture and UX research? Visit our resources page for recommended books and articles.