API testing is a type of software testing that involves testing application programming interfaces (APIs) directly and as part of integration testing to determine if they meet expectations for functionality, reliability, performance, and security. Since APIs lack a GUI, API testing is performed at the message layer.

What category does API testing fall under box?

It executes tests at the service or business layer. While unit tests are typically written by developers and take a white-box testing approach, API tests are usually written by the QA team and view the system under test ( SUT ) as a black box.

How many types of API testing are there?

Type of testingStage of softwarePerformance and load testingAs early as possible as these tests take timeRuntime error detection and security testingOngoing processesInteroperability and fuzz testingTesting stageValidation testingUser Acceptance testing