In this blog, we will be covering the difference between white box testing and black box testing (black box vs white box testing).
A software’s core coding and infrastructure are tested as part of white box testing while in black box testing, also known as “behavioral testing,” the tester is more concerned with what the software is expected to accomplish than with how it operates internally.
But before learning about the differences in the white box and black box testing approaches, we will first see a brief explanation of what is software testing, what is black box testing, and what is white box testing, and then will go through the black box vs white box testing discussion.
What is Software Testing?
Software testing ensures that an application that is bug-free and satisfies all the technical requirements as specified by the design and development team is being delivered to the client. It primarily seeks to gauge a software program or application’s specifications, functionality, and performance.
What is Black Box Testing?
An outline of the customer’s requirements serves as the main source for black-box testing. It is an additional kind of manual testing. It is a method of testing software in which the functioning of the program is looked at without knowledge of its coding or internal structure.
The software does not require any programming expertise. Black box testing can be applied to any kind of testing whether it is unit testing or integration testing or any other kind of testing.
In this approach, the tester picks a function, provides an input value to test its performance, and then determines whether the function is producing the desired results or not. The function passes testing if it generates the desired output; else, it fails.
What is White Box Testing?
The term “clear box,” “white box,” and “transparent box” refers to the capability of viewing the software’s inner workings through its exterior layer. The primary goal of white box testing is to examine the infrastructure of the application.
It necessitates programming expertise due to its emphasis on the pathways, circumstances, and branches of a program’s or software’s code. White box testing is carried out by developers.
Each line of the program’s code will be tested in this form of software testing by the developer. After completing white box testing, black box testing is carried out at which point they send it back to the developers for further work.
Difference Between Black Box Testing and White Box Testing
To better grasp the concept of black box vs white box testing, we will divide the comparison on the basis of various parameters, and then explain them one by one.
1. Algorithm Testing
White box testing is recommended for algorithm testing while black box testing is not.
2. Automation Difficulty
Automating black box testing is challenging because of the close ties between the tester and the programmer. Comparatively, automating white box testing is easy.
3. Code Implementation
Black box testing does not require code implementation. On the contrary, white box testing necessitates code implementation.
4. Code Specificity
Black box testing is appropriate and effective for long code sections. Code blocks that can introduce bugs can be ridden off in white box testing.
5. Detection of Mistakes
Black box testing doesn’t discover the problems in the code. White-box testing, however, allows for the finding of concealed mistakes. The code’s optimization is also possible in this type of software testing.
6. Documentation
Upon completion of the requirement specification document, black box testing may start. Once the design document is prepared in detail then only white box testing can begin.
7. Granularity
Black box testing has low granularity while white box testing has high granularity.
8. Knowledge of Inner Workings
Black box testing is a technique for testing software where the internal architecture, program, or code is concealed and unknowable.
Unlike closed box testing, white box testing requires the tester to be familiar with the software’s internal architecture, source code, and program.
9. Main Goal
Using black box testing mostly serves the purpose of defining consumer or corporate requirements. The primary goal of white box testing is to evaluate the code’s quality.
10. Other Names
Black box testing is also referred to as functional testing, data-driven testing, and closed-box testing. Clear box testing, transparent testing, or code-based testing are all different names for white box testing.
11. Performed By
Black box testing is performed by testers whereas developers are responsible for performing clear box testing.
12. Prior Knowledge
Without any prior knowledge of the operating system or programming language, even less experienced testers can test the application in black box testing. You’ll require a skilled tester with extensive experience to carry out white box testing though.
13. Programming Expertise
Black box testing does not require programming expertise. White box testing, on the other hand, necessitates a practical understanding of programming.
14. Techniques
Black box testing can be carried out using trial-and-error techniques. Branch coverage, path coverage, and statement coverage are the three main white box testing techniques.
15. Testing Hierarchy
Higher-level testing, including system testing and acceptance testing, is best suited for black box testing. Contrarily, lower-level testing, including unit and integration testing, is more appropriate for white box testing.
16. Time Requirement
Less time is needed for black box testing. The time needed for black box testing depends on whether the functional specifications are available or not.
Comparatively, transparent box testing requires more time. Due to extensive code, designing test cases takes a lot of time.
Black Box vs White Box Testing: A Comparison Table
Parameter | Black Box Testing | White Box Testing |
| Algorithm Testing | Recommended. | Not recommended. |
| Automation Difficulty | Implementation is easy. | Difficult to implement. |
| Code Implementation | Not required. | It is mandatory. |
| Code Specificity | Effective for long code blocks. | Problematic code blocks can be removed. |
| Detection of Mistakes | Doesn’t detect code issues. | Allows finding hidden code problems. |
| Documentation | Starts after the completion of the requirement specification document. | Can only be started after the completion of the design document. |
| Granularity | Low. | High. |
| Knowledge of Inner Workings | Not known. | Known. |
| Main Goal | Defining consumer or corporate requirements. | Evaluate code quality. |
| Other Names | Data-driven testing, specification-based testing, and closed-box testing. | Clear box testing, code-based testing, glass box testing, transparent testing, and structural testing. |
| Performed By | Testers. | Developers. |
| Prior Knowledge | Not required. | Required. |
| Programming Expertise | Not required. | Required |
| Techniques | Trial-and-error. | Branch coverage, path coverage, and statement coverage. |
| Testing Hierarchy | Higher-level testing. | Lower-level testing. |
| Time Requirement | Less. | More. |
Conclusion
After going through the above differences between black box and white box testing (black box vs white box testing), it is clear that to deliver a bug-free software product both types of testing are required to be carried out.
Please note that 100% testing is not possible in any situation. In order to increase the effectiveness of the application, the tester’s and developer’s main task is to find as many issues as they can.
A program’s complete functionality is checked using black box and white box testing. Understanding both testing methods is therefore essential.
An enthusiastic computer science engineer with experience working in Java applications. Skilled in C++, basics of Machine Learning, solving real-world problems, and passionate about learning new technologies. I also develop technical content to share knowledge and provide learning content.