What is Idempotency in APIs?

Updated Apr 28, 2026

Short answer

The property that making multiple identical requests has the same effect as a single request.

Deep explanation

Intermediate API design involves handling complexity and security. The property that making multiple identical requests has the same effect as a single request.

Real-world example

GitHub API using cursors for navigating large lists of commits.

Common mistakes

  • Not versioning the API from day one, leading to breaking changes.

Follow-up questions

  • Is PUT idempotent?
  • Is POST idempotent?

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