Chapter 5 – Test Management
System Under Test (SUT) – ISTQB Definition
Last Updated: July 12, 2026 · SoftwareTestPilot QA Team
Official ISTQB Definition
The system that is the object of testing.
In simple words
Common shorthand for whatever you're testing right now.
Exam tip
SUT is standard vocabulary in automation and performance testing.
Related terms
- Test ObjectWhatever you are currently testing — a component, a service, an app, a document.
- Test EnvironmentThe setup where tests run — servers, browsers, DBs, feature flags — ideally close to production.
- Test HarnessThe scaffolding around the code under test — the drivers that call it and the stubs that fake its dependencies.
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