Chapter 5 – Managing the Test Activities
Severity – ISTQB Definition
Last Updated: July 12, 2026 · SoftwareTestPilot QA Team
Official ISTQB Definition
The degree of impact that a defect has on the development or operation of a component or system.
In simple words
How bad the bug is technically — does it crash the app, corrupt data, or just misalign a label?
Exam tip
Severity is about impact and is set by testers; priority is about urgency and is set by the business.
Related terms
- PriorityHow urgently the bug should be fixed from a business point of view — a low-severity blocker for a demo can still be top priority.
- DefectA flaw in the product — code, requirement, or design — that could cause a failure when executed.
- FailureThe visible symptom — the app crashed, the calculation was wrong, the button did nothing.
Practice this term in the ISTQB Mock Test
40 CTFL v4.0 questions, 60-minute timer, instant scoring and chapter-wise breakdown.
Practice in Mock Test