API Testing in Katalon Studio: Step-by-Step Guide (2026)
API testing has become one of the highest-value activities a QA team can invest in. Because APIs operate at the business logic layer, below the user interface and above the database, tests written there are faster to execute, more stable across releases, and far cheaper to maintain than their UI counterparts. In the test pyramid, API tests occupy the middle tier: broader than unit tests, but a fraction of the cost of end-to-end UI suites.