Boundary Value Analysis In Software Testing

Boundary value analysis is a testing technique that involves testing the behavior of an application at its boundaries, both upper and lower limits, to determine how the application handles inputs that are at or near the limit values. This technique helps identify defects or errors that may occur at the boundary of a system, where unexpected behavior may happen.

Here is an example of how boundary value analysis can be applied to a simple scenario:

Suppose you have an application that accepts numerical inputs in the range of 1 to 100. You need to test this application to ensure that it handles input values correctly at the boundary limits.

Boundary value analysis would suggest that you test the application with inputs at the lower and upper limits, as well as inputs just inside and outside of these limits, to identify any issues that may arise.

For example, you might test the application with the following inputs:

Input value of 0: This is below the lower limit and should be rejected by the application.
Input value of 1: This is at the lower limit and should be accepted by the application.
Input value of 50: This is within the valid range and should be accepted by the application.
Input value of 100: This is at the upper limit and should be accepted by the application.
Input value of 101: This is above the upper limit and should be rejected by the application.

By testing the application with inputs at and near the boundary values, you can identify any defects or errors in how the application handles these values. This can help ensure that the application functions correctly and meets the requirements for which it was designed.