What is IActionResult in Web API?

Updated Apr 28, 2026

Short answer

IActionResult represents HTTP response.

Deep explanation

It provides flexibility to return different response types like Ok, NotFound, BadRequest.

Real-world example

Returning 200 OK or 404 Not Found.

Common mistakes

  • Returning raw objects instead of proper responses.

Follow-up questions

  • What is Ok()?
  • Why IActionResult?

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