Boundary Value Analysis

Updated 22 Jul 2026

•
def
- •
  a black-box test case design technique that tests boundary values of input variables, since values near the boundary have a higher probability of causing errors
•
rationale
- •
  test cases created using boundary values are most likely to expose errors
•
approach
- •
  identify minimum and maximum values of each input variable
- •
  create test cases for: value just below lower boundary, lower boundary, middle range values, upper boundary, value just above upper boundary
•
example
- •
  age variable with valid range 18–30
- •
  test cases: 17, 18, 24, 30, 31
•
uses both valid and invalid partitions
- •
  testing in adverse (boundary-exceeding) conditions is also essential
•
related

Linked references 4