Black Box Testing (BBT)

Black Box Testing:

The technique of testing without having any knowledge of the interior workings of the application is Black Box testing. The tester is oblivious to the system architecture and does not have access to the source code. Typically, when performing a black box test, a tester will interact with the system’s user interface by providing inputs and examining outputs without knowing how and where the inputs are worked upon.

A black box software tester selects a set of valid and invalid input and code execution conditions and checks for valid output responses.Black box testing is also known as functional testing.

A search engine is a simple example of an application subject to routine black box testing. A search engine user enters text in a Web browser’s search bar. The search engine then locates and retrieves related user data results (output).


Advantages :

  • Well suited and efficient for large code segments.

  • Code Access not required.

  • Clearly separates user’s perspective from the developer’s perspective through visibly defined roles.

  • Large numbers of moderately skilled testers can test the application with no knowledge of implementation, programming language or operating systems.


  • Limited Coverage since only a selected number of test scenarios are actually performed.

  • Inefficient testing, due to the fact that the tester only has limited knowledge about an application.

  • Blind Coverage, since the tester cannot target specific code segments or error prone areas.

  • The test cases are difficult to design.

Types of Black Box Tesing:

1) Equivalence partitioning

2) Boundary value analysis

3) Decision table testing

4) State transition testing

5) Use case testing

883 total views, 1 views today

Share this OnShare on FacebookTweet about this on TwitterShare on LinkedInShare on Google+

Leave a Reply