Tree-testing in Information Architecture (IA)

Tree-testing is a method to evaluate the navigation structure of a website or application through testing a “pure” text tree of categories and subcategories, without visual design, search engine, or UI elements. The goal is to check if people can quickly and confidently find the correct place for specific tasks.

How it works

• Create a hierarchical tree: list of sections and sub-sections.
• Give realistic tasks: “Where would you look for a return policy?”
• Participants click on nodes in the tree until they reach the answer.
• Paths, time, and success are recorded, and the tree is optimized.

What it measures

• Success rate: percentage of participants who reached the correct place.
• Directness: whether they reached without deviations.
• Time to first click and time to success.
• Path length: number of steps to the goal.
• Wrong turns: where the labels and structure are misleading.

When to use it

• Redesign or expansion of navigation/menu.
• After card sorting, to validate the proposed structure.
• At high bounce/exit or low discoverability of key information.
• To support SEO and help centers through better finding of content.

Step-by-step process

• Determine the critical tasks of the users.
• Build a simplified text tree (without visual elements).
• Create 8–12 realistic tasks, without naming categories.
• Invite 30–100 participants from the target audience (even 10–15 give valid signals).
• Collect data and analyze: successful/incorrect paths, “stuck streets”.
• Rename, move or merge nodes and repeat the test.

Tools

• Optimal Workshop (Treejack)
• UserZoom
• Maze
• UXtweak
• Useberry

Tips and best practices

• Test the labels and structure, not just the structure.
• The scenarios should reflect real goals (prices, delivery, contact, top categories).
• Use metrics for prioritization of changes, not just opinions.
• Iterations in short cycles to see the effect of corrections.

Common mistakes

• Suggesting the correct category in the task text.
• Too detailed tree, which tires and blurs the signals.
• Random participants outside the target audience.
• One-time test without validation after changes.

Mini example

Task: “Where would you look for information about delivery terms?”

• Correct path: Home → Help → Delivery and returns → Delivery terms.
• If most people go to “Prices and payment”, probably the labels or structure are misleading.

Link to other methods

• Card sorting: generate hypotheses for grouping and naming.
• Tree-testing: validate whether the proposed tree works in practice.