What is White Box Testing? A Complete Guide With Tools & Techniques

White box testing has various names glass box testing, structural testing, transparent testing, and clear box testing. These all names indicate that this type of testing process is not opaque. You can see the internal structure, codes, designs, and working of the application, website, or any software you are testing.

All the apps go through a complete process of testing. Our on-demand app development company performs white box and black box testing as per the need of the product.

Professionals check all the logical decisions are working impeccably and the loops executed after coding is within their operational bounds. They can perform data flow testing, control flow testing, and many other types of testing while being aware of what is happening inside the software.

However, often many people seem confused between white box testing and black box testing. In this post, I will clear all your doubts related to different types of testing and explain to you almost everything related to white box testing.


What Is the Difference Between White Box Testing and Black Box Testing?


I want you to understand everything from scratch about software testing so that you will not be left with any doubt at the end of the blog. That’s why first understand the difference between white box testing, and black box testing.

These both come under a software testing method. Moreover, there is no good or bad testing method. Both the testing processes are necessary and complementary. Here are the points that explain the difference.

  1. In the open box testing (White box) tester knows the internal security holes and knows about the internal workings. However, in black box testing tester doesn’t have a thorough knowledge of the internal designs and functions of the application.
  2. You don’t need to implement code for black box testing. Whereas, code implementation is vital in white box testing.
  3. The tester must have knowledge of code implementation in white box testing, while he needs no knowledge of the same for black box testing.
  4. Black box testing is the task of software developers. Whereas, software developers perform the white box testing.
  5. Black box testing is often called outer or external testing, while another type of testing is called an inner or internal type of testing process.
  6. The black box is the least time-consuming, whereas the white box is the most time-consuming.
  7. Many call it closed box testing because testers can’t know about the internal workings and source code changes during black box testing.
  8. An example of white box testing is: Giving input to check and verify loops. And searching for something on Google by keywords is an example of black box testing.

What Is a Clear Box Testing or Transparent Box Testing?



White box testing in software engineering Is a vast yet interesting concept. Often people get confused between different terms of white box testing. There are two terms popular clear box and transparent box. You, as a tester can see internal changes in the coding, designs, and functions of the app while testing.

On the other hand, the transparent box name indicates the meaning itself, which you as a tester can see through the app or its internal structures, which is why it got the transparent testing name. Many times developers call it code-based testing as well. Now I hope, you will not confuse if I use alternative names throughout the blog.

What Do Testers Verify in Glass Box Testing?

What exactly tester want to find by testing? And what are the reasons to do testing? You will get to know everything that white box testing involves. Since testing is part of all the software development models, you can’t skip it in any model.

  • Tester find the internal security holes
  • A broken and poorly structured path
  • Hidden errors
  • The flow of particular inputs using code
  • Testing of objects, functions, and statements in a software

Testing has many purposes and is a crucial process to ensure high-performing software. A tester tests internal structures, source code, and control flow statements and creates test cases.

Testers don’t do all the tasks manually, they take the help of some white box testing techniques and tools that will discuss in upcoming sections.

Types of White Box Testing

Some white box testing techniques make the life of testers easy so they can complete the task fast and effectively. We will read about each white box testing technique in this post for error-free website development.

  1. Unit testing
  2. Statement coverage
  3. Branch Testing Coverage
  4. Security Testing
  5. Mutation Testing

Here are some types of white box testing. Scroll down to know their details.

1. Unit Testing

Testers test each unit or an individual component of an application, website, or software. This process validates unit components and the performance of the software. So, Unit testing is the first level of functional testing.

During the Software development lifecycle, this testing technique is performed as a single testable part. It is a detailed testing in which isolated parts or codes are tested.

2. Statement Coverage

In the statement coverage testers analyze the functionalities and working of the software. They ensure every function is executed at once. They also make sure the functions execute in order.

In the statement coverage testing process, every statement should be tested at least and in a proper sequence. When developers complete writing a line of code, it is called a statement, and a program has many statements of code.

3. Branch Coverage

When developers perform white box testing, most of them use branch coverage because this is a comprehensive technique. Branch coverage is conditional testing in which the “If statement” is used. It has two branches; true and false.

In branch coverage, you have to validate that each branch is executed at least once during testing. There will be two conditions.

  1. If it is true
  2. if it is false

You can use a while statement when you feel there can be two or more outcomes.

4. Security Testing

In-depth knowledge of the programming languages is needed for white box testing. Security testing is also one of the integral parts of software testing for which you need to know a programing language.

Although you have to write a few lines, it should be complete and purposeful so that you can find weaknesses, threats, and risks in the software. You can find potential ambiguities and vulnerabilities in an application with the help of a security testing technique.

5. Mutation Testing

Mutation testing is a different type of testing technique in which developers make test cases. They purposely add errors into a program during testing. It is to check whether the test case can detect the error or not.

Some mutations or modifications are done in an original program to check how it will react and what type of error it can show. The purpose of creating a mutation is simple, whether each mutant creates an output or not.

But, make changes in the simple programs first and then in the complex programs. This way, if you make any mistake, you can resolve it fast.
Some Other Software Testing Types

Apart from the above, white box testing involves some more types, static code analysis, dynamic analysis, data flow testing, and control flow testing are other white box testing methods. In static analysis, you have to check the software without code execution.

In dynamic analysis, code is executed in a run-time environment. You can check the dynamic behavior of the code. Moreover, developers use data flow testing to check the control flow of the program.


Tests Included in White Box Testing

Various types of testing are done as per the need of the software. Since different businesses want different features and functions in their products, developers must do testing accordingly.

The cost of custom software development projects also increases because developers have to use different types of white box testing methods.

  1. Path Testing
  2. Loop Testing
  3. Testing Based on Memory Perspective
  4. Test Performance of the Programming language

1. Path Testing

Every path is considered in this type of testing. Well, many developers think it is a time-consuming task. You can design test cases in path testing. It is also called path coverage. Path coverage helps to find a set of linearly independent paths, and test cases are made for each path.

2. Loop Testing

In this white box testing method, different types of loops are tested. They are single loops, nested loops, concatenated loops, and dependent and independent loops. You can also call it controlled testing. Because it is performed to validate the loops. It fixes the infinite loop repetition problems.

3. Testing Based on Memory Perspective

As the prototype of software or hardware is completed, you can go for this type of testing. Many times memory-based problems are the most difficult to solve. So, developers have to follow the best practices for testing based on a memory perspective.

4. Test Performance of the Programming language

The heading indicates that you have to check the performance of a programing language. Well, this is initial testing before you start programming because finding the most suitable programming is a must for application development.

Top 4 White Box Testing Tools

Whether you are developing an app or a website for your business, you have to be sure that your software has no errors. Checking all the errors manually is not possible, so you as a developer or tester have to use various tools.

You can hire a reputed web development company because professionals can use tools effectively and test your software better. That’s why you should hire a top web development company.

Check out the best white box testing tools in the space below.

  1. HTMLUnit
  2. EclEmma
  3. PyUnit
  4. CppUnit

1. HTMLUnit

This tool has JavaScript support. It comes under the headless browser testing process. HTML Unit driver is one of the most popular headless browsers. It is a lightweight tool to implement a web driver. HTMLUnit white box testing tool is the fastest tool without a GUI.

2. EclEmma

It is a free JavaCode coverage tool for testing software’s outer shell. Its test cycle is fast which is why many developers use it for testing. You can get summarized coverage results highlighted in the Java source code.

3. PyUnit

PyUnit is the third tool in the series of system testing tools. It is a Python Unit testing framework. You can test any specific module without accessing any dependent code.

4. CppUnit

CppUnit is a unit testing tool. It is a C++ port of the famous JUnit framework. In the white box test, CppUnit is used when you need to do GUI based supervised tests.

These white box testing tools help to improve the performance of a software application. Today people know the advantages of having a mobile app, so a lot of businesses want customized software for profit. Testing tools help to test applications fast and effectively. It helps developers to complete the projects on time.

Most developers test MVP first and then the final product. So, if a software development creates create MVP, it will thoroughly test your software product.

Wrapping Up

White box testing is a crucial testing process in SDLC. Now you have learned not only about white box testing but also black box testing and various techniques and tools that make the process of testing easy. With the white box test, you can remove logical errors, structural problems, and problems with specific components.

We at Technource follow the best box testing approach to testing software according to the need. Our professional developers first understand the requirements of the client, analyze the project and use the best technologies. You can contact us at any time and ask questions from our experts free of cost and hire developers for your app idea.



Mr. Sanjay Singh Rajpurohit, An early-aged entrepreneur who always leads his team from the front and achieved success. As the founder & CEO of Technource, a top mobile app & Web development company, he made a global presence in a short time by offering custom software development, premium mobile apps, and website development services to global clients. In his free time, he loves writing. He is featured on Hackernoon, Dzone, Enlear Academy, Articlesfactory, and much more websites.

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