Tree testing your navigation
What tree testing is
A tree test presents the structure of a site or app as a text-only hierarchy of topics and sub-topics. Participants get a task and click through the levels until they find where they would look. With no layout, colour or search, the test isolates one question: do the labels and grouping work?
Write good tasks
- Base tasks on real goals, such as “Find out how to change your delivery address”.
- Do not use the exact words from the labels, or participants will just match words.
- Keep each task focused on one answer location, and keep the total number of tasks small.
- Decide in advance which location counts as correct.
What to measure
Success
The share of participants who ended in a correct location.
Directness
Whether they reached the answer without backtracking. Frequent backtracking suggests unclear labels.
Time
Longer times can signal hesitation, especially when many people are slow on the same task.
First click
The first choice shows which top-level label people expect to lead to the answer.
Look at where wrong answers cluster. If many people choose the same wrong category, that category may be competing with the right one, and its label or position deserves a change.
Iterate on labels
Tree testing is most useful when repeated. A first round usually exposes a few weak labels; later rounds confirm whether the changes helped.
- Replace internal or abstract terms with words people use.
- Make sibling categories clearly different from each other.
- Move an item if people keep looking for it in another branch.
- Avoid very deep hierarchies; each extra level is another chance to choose wrongly.
Change one area at a time where possible, so that a better or worse result can be traced to a specific change.
Pair it with card sorting
The two methods answer different questions and work well in sequence.
- Use a card sort to build a structure from how people group content.
- Use a tree test to verify that people can find items in that structure.
- Rename or regroup the weak areas.
- Test again with new participants.
A tree test checks the structure, not the interface. Visual design and search are tested separately.
This guide was drafted with AI assistance from public standards and references. For the exact wording of a standard, use the sources listed above.