Advanced – Usability & Accessibility
System Usability Scale (SUS) – ISTQB Definition
Last Updated: July 12, 2026 · SoftwareTestPilot QA Team
Official ISTQB Definition
A ten-item questionnaire that gives a subjective assessment of usability of a system, producing a single score from 0 to 100.
In simple words
A quick 10-question survey turned into one usability score.
Exam tip
A SUS above 68 is above average; above 80 is excellent.
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