Usability testing

What it means

Usability testing means observing real users as they perform tasks on a website or in an app, such as buying, registering or filling in a form. The aim is to find out where they get stuck, what they do not understand and what confuses them, so that those spots can be fixed.

It is one of the core methods of UX design. Unlike surveys, where people say what they would do, testing shows what they actually do. The gap between stated and real behaviour is often surprisingly large and reveals problems the creators never thought of.

Just a few tests with five users usually uncover most of the serious problems. Testing need not be expensive or complicated: it is enough to prepare realistic tasks, watch how people carry them out and note where they hesitate or make mistakes.

How it works in practice

Testing pays off early, for example on sketches or during prototyping, when changes are still cheap. Later the finished site is tested before launch and then regularly after major changes to make sure new features do not make life harder for users.

Qualitative testing works well alongside quantitative methods. Heatmaps show where people click and how far they scroll, and A/B testing checks which of two variants performs better. Usability testing, in turn, explains why people behave the way they do.

For an accounting firm's website, tasks might include finding the price of bookkeeping, calculating a price in the calculator or submitting the contact form. Removing obstacles in these steps directly raises the conversion rate and the number of enquiries.

What to watch out for

Tests should be run with people who resemble real customers, not with colleagues who already know the product. The moderator must not give hints or steer the user, or the results will be skewed and problems will remain hidden.

Usability testing does not replace an accessibility check against WCAG. People with disabilities, such as screen reader users, run into different barriers, so it is wise to include them in testing or carry out a separate accessibility audit.