Boundary value analysis: what, how and why?

What is boundary value analysis?

Boundary value analysis is a test technique used to verify that software functions correctly when processing boundary values, such as the minimum and maximum values of input parameters. It is important to apply this technique because boundary values are often a source of errors in software applications.

Example application - age limit

A good example of boundary value analysis concerns testing a form for entering age. If the age limit for the form is between 18 and 65 years, the software must function correctly when entering an age within these limits. A tester must be able to apply boundary value analysis to verify that the software responds correctly when inputting values that fall just within or just outside the limits, such as 18, 65, or 66 years. What about someone who turns 18 on April 2, 2023, and the form is tested on April 1, 2023?

Other example applications You can also apply boundary value analysis to input financial data, such as the maximum or minimum value of a transaction amount. Or what about entering temperature values in a climate control system?

Read tip! Code coverage testing: improve software quality

Why is boundary value analysis important for cross-functional teams?

By using boundary value analysis, as a software tester, you can ensure that the software functions correctly in all situations where boundary values play a role. The analysis is especially important for cross-functional teams involved in the development and testing of software. By using this technique, cross-functional teams can improve the quality of software and detect errors at an early stage. This is important to prevent delays and additional costs in the development process.

Because boundary value analysis also provides a common language and methodology for testing boundary values, it leads to better collaboration between cross-functional teams. This also results in fewer misunderstandings and more efficient communication between team members.

What to look for in boundary value analysis?

If you are going to perform boundary value analysis, there are a few things to keep in mind. We summarize these for you here:

• Identify the boundary values: determine which input parameters have boundary values and which values are considered minimum or maximum values;
• Define the test cases: create test cases that test the input parameters for values that fall just within and just outside the boundary values. Take into account different scenarios and edge cases;
• Execute the test cases: run the test cases and carefully review the results. Make sure to accurately map out which specific cases you want to test beforehand!
• Document the findings: document the findings of the tests and the results. Analyze the results to identify any errors and issues.

Want to know the exact steps? We cover them in the e-learning TMap Quality for cross-functional teams.

Tips for creating test cases

• Test multiple scenarios: test input parameters on different scenarios and edge cases to ensure that all possible situations are covered;
• Use automated tests: use automated tests to speed up the process and improve accuracy;
• Check the results: carefully check the results of the tests to ensure that the software functions correctly when inputting values just within and just outside the boundary values;
• Document the results: document the results of the tests and any problems and errors found. This helps to improve the quality of the software and detect errors at an early stage.

Boundary value analysis for better cross-functional teams

Boundary value analysis helps to detect and improve errors in software and can lead to greater efficiency and higher quality in the development process. If you want to broaden or deepen your knowledge of boundary value analysis and other software testing skills, we recommend the e-learning TMap Quality for cross-functional teams. This e-learning provides practical knowledge and skills in the field of software testing, including boundary value analysis, and is specifically designed for cross-functional teams.

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