What is binary classification?

Updated May 15, 2026

Short answer

Binary classification involves predicting one of two possible classes.

Deep explanation

The model learns a decision boundary separating two classes, often using sigmoid-based outputs or probabilistic thresholds.

Real-world example

Fraud detection: transaction is fraudulent or not.

Common mistakes

  • Assuming class distribution is always balanced.

Follow-up questions

  • What models are commonly used for binary classification?

More Classification interview questions

View all →