15 Difference Between Black Box Testing And White Box Testing

Learn the difference between black box testing and white box testing. The basis of comparison include: description, types, complexity of performance, basis of test case design and nature of the process among others.

  What is Black Box Testing?

Black box testing also referred to as closed-box, opaque-box, eye-to-eye, behavioral or specification-based testing, is a technique of software testing that examines the functionality of an application without opening into its internal structures or workings. It can be done manually or through automation.  This method can be used virtually to every level of software testing such as unit, integration, regression, system and acceptance. The main desire of black box testing is to confirm that end users will be able to use the product.

There are two fundamental types of black box testing which includes Functional Testing and Non-functional testing. Functional testing, deals with the functional requirements or specifications of an application, whereas Non-functional Testing deals with non-functional aspects such as usability, load, performance, compatibility, stress and scalability.  In order to systematically test a set of functions, it is necessary to design test cases. Testers can create tests cases from requirement specification document using the following testing techniques:

Equivalence partitioning

• Graph-based testing techniques
• State transition testing
• Error guessing
• Comparison testing
• Boundary value analysis
• Decision table testing

What Are Some of The Advantages of Black Box Testing?

1. The method is very effective especially when used on instruments with a large software system.
2. Black box testing is very perfect in detecting errors in functional specifications.
3. Test cases in black box testing can be designed as soon as the functional specifications are complete.
4. The person using black box testing method does not need to possess vast knowledge in software and programming.
5. Black box testing is capable of detecting errors at early stages of testing.

What Are Some of the Disadvantages of Black Box Testing?

1. It is difficult to design test cases without clear functional specifications.
2.  When using black box testing, chances of having undetected paths/logics and errors are high.
3. Chances of repeating tests already performed by the programmer are high.
4. It is difficult to achieve 100% test run cover in cases where the application is hugely complex.
5. It is difficult to identify complex logics (paths) if the test cases are not developed based on specifications.
6. Black box testing can be redundant, as it often tests the same functions that may also be tested during unit testing.

Also Read: Difference Between System Testing And System Integration Testing

What Is White Box Testing?

White-box testing also referred to as structural testing, transparent box, glass box, clear box testing, is a method of software testing that tests internal structures or workings of an application as opposed to its functionality. In this testing method, internal understandings of the system together with programming skills are used to design test cases. The tester chooses inputs to exercise paths through the code and determine the expected outputs.

This method can be used at level of software testing such as unit, integration, regression and system. White box testing does not account for errors caused by omission and all visible code must be readable.

Techniques of White Box Testing

White box test design techniques include the following code coverage criteria:

• Data flow testing
• Branch testing
• Path testing
• Prime path testing
• Modified condition/decision coverage
• Statement coverage
• Control flow testing
• Decision coverage

What are the Advantages of White Box Testing?

1. It is very effective when compared to black box testing especially when it comes to detection of hidden errors in the code.
2. White box testing is very comprehensive in testing software; it is thorough and covers almost the entire paths and codes of the software.
3. White box testing can be started at the initial stages of software development life cycle (SDLC).
4. The method is very effect when it comes to detection of dead codes easily.
5. The white box testing technique is simple to automate and this helps to save testing time.

What are the Disadvantages of White Box Testing?

1. Though white box may be quite effective when compared to black box testing, however, through this method it is not possible to cover every possible condition for testing.
2. The technique of white box testing is complex and costly.
3. The testing approach is very thorough and requires a person with vast knowledge and skills in programming.

Also Read: Difference Between Unit Testing And System Testing

The Difference Between White Box Testing And Black Box Testing In Tabular Form