BVA (Boundary Value Analysis)

What is Boundary Value Analysis?

Boundary Value Analysis (BVA) is a black box test design technique based on the observation that defects often occur at the boundaries of input ranges rather than in the middle.

How BVA Works

For a given valid range, testers create test cases for values:

• Just below the minimum boundary.
• At the minimum boundary.
• At the maximum boundary.
• Just above the maximum boundary.

For example, for an input field accepting values from 1 to 100, BVA would test 0, 1, 100, and 101.

Why BVA is Effective

Boundary conditions are a common source of off-by-one errors and incorrect comparison operators (e.g., using < instead of <=), making BVA a highly efficient technique for catching real defects with relatively few test cases.