What is useCallback and when should it be used?

Updated May 6, 2026

Short answer

useCallback memoizes functions to prevent unnecessary re-creations.

Deep explanation

It is useful when passing callbacks to optimized child components that rely on reference equality.

Real-world example

Optimizing re-renders in lists and child components.

Common mistakes

  • Using it without memoized children, adding unnecessary complexity.

Follow-up questions

  • When does useCallback help performance?
  • Does it always prevent re-renders?

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