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Fundamentals

API Testing Overview

What API testing is, why teams invest in it, and how it fits next to UI and unit tests.

API Test Lab6 min read

API testing validates HTTP APIs directly—without driving a browser. It is how teams catch contract bugs, auth issues, and performance regressions before users see them.

Why API testing matters

  • Faster feedback than end-to-end UI tests for backend changes.
  • Stable selectors: URLs and JSON bodies change less often than DOM nodes.
  • Clear expectations: status codes, headers, and payloads are easy to assert.

What to verify first

Start with a happy path for each critical endpoint, then add negative cases (401, 404, 422) and security checks (auth, rate limits) as you mature.

Next steps

Open API Test Lab to send your first request, save it, and reuse it in your team workflow.

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