Non-functional Testing
Non-functional testing verifies quality characteristics such as performance, security, usability, reliability, maintainability, and scalability rather than specific business functions.
“Testing performed to evaluate that a component or system complies with non-functional requirements.”
(Definition reproduced from the ISTQB Glossary. Copyright belongs to ISTQB.)
View the complete ISTQB GlossaryWhat is Non-functional Testing?
It evaluates how well the system performs under various conditions instead of what the system does.
Quality characteristics: Focuses on system attributes.
Requirement validation: Confirms non-functional requirements are satisfied.
Broad scope: Includes many specialized testing types.
Real World Example
A regulated product team is preparing a release where Non-functional testing appears in reviews, test design conversations, or defect triage rather than as an isolated glossary word.
The risk is that the team treats Non-functional testing as interchangeable with nearby ISTQB terms. That makes test scope blurry and can lead to weak evidence for the release decision.
The tester anchors the discussion in the official definition, asks where the concept appears in the product, and designs examples that show the difference between Non-functional testing and similar ideas.
The page becomes useful in practice because Non-functional testing is connected to a specific testing decision, not memorized as a detached definition.
Practice Questions
Question 1
Which statement BEST describes Non-functional testing in the context of ISTQB terminology?
Question 2
A tester needs to explain Non-functional testing to a non‑technical stakeholder. Which approach is MOST appropriate?
Test your knowledge with real ISTQB-style questions
You’ve learned Non-functional Testing. Test your understanding with topic-specific questions in our Mock Exams.