What is the difference between IActionResult and ActionResult<T>?

Updated Apr 28, 2026

Short answer

IActionResult is non-generic; ActionResult<T> includes type safety.

Deep explanation

IActionResult allows returning different result types, while ActionResult<T> provides compile-time type safety and simplifies API responses.

Real-world example

Returning typed API responses.

Common mistakes

  • Overusing IActionResult without type safety.

Follow-up questions

  • Why use ActionResult<T>?
  • When use IActionResult?

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