What is regression testing?

Updated May 6, 2026

Short answer

Regression testing ensures new changes don't break existing functionality.

Deep explanation

It involves re-running existing tests after code changes. It ensures stability of previously working features.

Real-world example

Testing checkout flow after adding discount feature.

Common mistakes

  • Skipping regression tests after minor changes.

Follow-up questions

  • When should regression testing be done?
  • Is automation useful here?

More Unit Testing interview questions

View all →