What is label encoding and when should it be used?

Updated May 16, 2026

Short answer

Label encoding converts categories into numeric labels.

Deep explanation

Each category is assigned a unique integer. It is useful for ordinal data but can mislead models if used on nominal categories.

Real-world example

Used in ranking systems like education levels.

Common mistakes

  • Applying label encoding to unordered categories like country names.

Follow-up questions

  • Why is label encoding risky?
  • What is ordinal encoding?

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