What is multi-class classification and how is it different from binary classification?

Updated May 17, 2026

Short answer

Multi-class classification predicts more than two classes, while binary classification predicts two classes.

Deep explanation

Binary classification deals with two labels (0/1), while multi-class classification handles multiple categories. Algorithms handle multi-class problems using strategies like One-vs-Rest or Softmax-based models. Evaluation metrics must also be adapted accordingly.

Real-world example

Handwritten digit recognition (0–9 digits).

Common mistakes

  • Using binary evaluation metrics for multi-class problems.

Follow-up questions

  • What is One-vs-Rest strategy?
  • What is softmax regression?

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