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Session Summary

How to test software which has many combinations of inputs, without getting swamped by an exponential explosion.


Find All-Pairs Testing on the Knowbility Learning Center

"All-pairs testing" (also known as "pairwise testing" or "combinatorial testing") is a technique for efficiently testing any software which has many input variables. In general, if we want to test our software thoroughly, we're often faced with the daunting prospect of testing all of the input variables in all of their combinations. This often means that we would need to run hundreds or thousands of tests. So we often - quite reasonably - give up on the idea of thoroughness. "All-pairs" testing addresses this problem by using clever tricks to reduce the number of tests (by more than 90% in many cases) while still achieving "pretty good" test coverage. The application of "all-pairs" testing to digital accessibility is clear, because we often want to test with different combinations of operating system, browser, viewport size, page template options, form field values, and so on - but for us to test every combination of those input variables would be impractical.

Practical Skills

  • Learn what all-pairs testing is useful for.
  • Learn how to do all-pairs testing with the help of Microsoft's "PICT" (Pairwise Independent Combinatorial Tool).
  • Learn advanced options for specific use cases.