# Mutation Testing

Deliberately breaking code to check tests notice.

## What is **Mutation Testing**?

**Mutation testing** makes small changes to your code on purpose and checks your tests catch them, measuring how strong the tests are.

Level: Master · [More Unit Testing terms at this level](https://www.ask-codey.com/glossary/subjects/unit-testing/master)

Updated: September 27, 2026

Source: https://www.ask-codey.com/glossary/mutation-testing