What is the time complexity of Merge Sort?

Updated Apr 28, 2026

Short answer

O(n log n) in all cases.

Deep explanation

Divide and Conquer is essential for efficient algorithms. O(n log n) in all cases. It transforms a large, complex problem into manageable chunks, reducing the overall computational effort compared to brute-force approaches.

Real-world example

Searching for a word in a physical dictionary.

Common mistakes

  • Forgetting the base case, leading to infinite recursion/StackOverflow.

Follow-up questions

  • Is Binary Search better than Linear Search?

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