Guerilla testing

Before you do other kinds of testing of prototypes/concepts, do a quick round of testing with colleagues, or client people, or passers-by to identify the big obvious problems with your product/prototype/concept or your testing plan.

Good for:

  • quick feedback from someone not familiar with the concept
  • identifying glaring problems with the concept/prototype, or testing techniques before more expensive testing

Bad for:

  • robust, representative results
  • because your colleagues or the client's staff know the area well already, you may overlook stuff that's not so obvious to normal people

How to use

  • Make a basic version of what you want to test, and set up the test exactly as you would in the real testing. Testing sketches in the form of a 'paper computer' can be faster than making a clickable prototype from digital designs
  • Grab a few colleagues and run through the test with them. Observe any snags in the testing technique and note down any problems they identify.
  • Alternatively, sit in a cafe and offer to buy people a coffee and snack in return for 10mins of their time running through the test.
  • Revise your prototype/stimulus/testing techique as appropriate.


Some of the bigger problems with your idea/prototype and/or your testing technique.


This can take as little as 30mins, or as much as half a day

What you need

  • A testing plan
  • A prototype or sketches to use in testing
  • Money to pay for cake & coffee (if you're testing in a cafe)
  • A cafe that's happy for you to sit there all afternoon (if you're testing in a cafe)




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