Itqualityassurance
Summary: Elaborate usability tests are a waste of resources. The best results come from testing no more than 5 users and running as many small tests as you can afford.
- Why are there 5 users for usability testing?
- What is a good sample size for usability testing?
- How many people should test a product?
- Why 5 participants in qualitative research?
Why are there 5 users for usability testing?
What's so magical about the number 5? Given that the probability of a user encountering an error during testing is 31%, according to Jeff Sauro of MeasuringU, testing just 5 users would turn up 85% of the problems in an interface.
What is a good sample size for usability testing?
For really low-overhead projects, it's often optimal to test as few as 2 users per study. For some other projects, 8 users — or sometimes even more — might be better. For most projects, however, you should stay with the tried-and-true: 5 users per usability test.
How many people should test a product?
The 5-user rule was promulgated by Nielsen (2000) in his article Why You Only Need to Test with 5 Users. Based on the studies he and Landauer conducted, Nielsen argued that the number of usability problems found in a test decreases after the fifth user.
Why 5 participants in qualitative research?
That the probability of someone encountering an issue is 31%
Based on these assumptions, Jakob Nielsen and Tom Landauer built a mathematical model that shows that, by doing a qualitative test with 5 participants, you will identify 85% of the issues in an interface.
