Understanding Black Box Testing — Types, Techniques, and Examples

What is Black Box Testing?

White box vs. Black box testing

Examples of Black box testing

Types of Black box testing

Techniques of Black box testing

  1. Equivalence Partitioning
    In this type of Black box testing technique, the inputs that behave homogeneously or yield similar outcomes are divided and grouped under one category. One input value from each group is picked and tested. For every group, one representative value is selected and tested. Testing each value in the group would be time-consuming. In this technique, only the representative value is tested from each group, making it easier to test many inputs at once, maintaining test coverage, and reducing rework.
  2. Boundary Value AnalysisIt is a popular black box testing technique that works on similar lines of equivalence testing. However, instead of testing the representative value from each group, this technique tests the boundary value of each input group (including both valid and invalid inputs). It is observed that applications face problems near the boundary, which means that the limit after which the system starts behaving differently.
  3. Decision Table TestingThis technique is appropriate in conditions where the functionalities have logical input between them, like if/else conditions. Here different input combinations are considered. We use conditions (inputs) and actions (outputs) to examine system behavior using decision tables.
  4. State Transition TestingIn this technique, the inputs/outputs and system states are considered in the entire testing phase. It tests the software application for a sequence of transitions of test inputs. It checks the system behavior changes depending upon what events have occurred/ or what input value is given. Events set off states which become scenarios that the testers test. For example: When a user enters a wrong password thrice, all three inputs will be sent to the login page. The third attempt will produce an error message for the user. This method considers all three system states and passes only the right state sequence.
  5. Graph-based testing
  6. A graph is prepared for the objects that the application consists of. Then based on this object graph, the relationship between each object is figured out, and a test is written to discover errors. It visualizes the flow and correlation of inputs and outputs.
  7. Error guessing technique:
  8. This testing technique is entirely experience-based. Here, the tester guesses the erroneous aspects (input/output) of the application. The judgment is solely based on his previous experience with the software behavior, functionalities, and impacts on end-user experience.





pCloudy is the most powerful cloud-based App Testing Platform. Brand Marketing @ pCloudy (www.pcloudy.com)

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pCloudy is the most powerful cloud-based App Testing Platform. Brand Marketing @ pCloudy (www.pcloudy.com)

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