Chapter 2 – Testing Throughout the SDLC
Component Testing – ISTQB Definition
Last Updated: July 12, 2026 · SoftwareTestPilot QA Team
Official ISTQB Definition
A test level that focuses on individual hardware or software components. Also known as unit or module testing.
In simple words
Testing the smallest testable pieces of code (a function, class, or module) in isolation, usually by developers.
Exam tip
Component testing is the first test level in the CTFL v4.0 test pyramid and typically uses stubs, drivers and mocks.
Related terms
- Integration TestingAfter units work alone, you plug them together and check the seams — API calls, data hand-offs, contracts.
- Unit TestingSame as component testing: developers verify one small piece of code at a time with fast, automated tests.
- White-Box TestingYou design tests using knowledge of the code — branches, statements, paths — to hit specific structural coverage targets.
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