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Do you trust your tests?

The typical test suite detects only 55%* of common bugs even with high code coverage.
Fixing the remaining 45% of the bugs after you deploy will cost you more than if you take action now.

* Average value based on research with open-source projects.

Average bug detection of tests

Average bug detection of tests


We have re-imagined unit testing

By using a metric that is far more accurate than code coverage, Mutator shows your test’s bug-detection quality.
Simple bugs, nasty bugs, off-by-one errors and more, Mutator takes everything into account.

off by one error

Mutator is based on research

Mutator uses decades of deep research to include only the mutations that matter.
It also uses modern techniques like selective mutation to make it very accurate, very fast and light-weight.


Improving your tests has never been this easy!

With an intuitive GUI, Mutator stays out of your way so you can achieve your goal: to improve your code by improving your tests!
No installation, configuration or messy setup. Mutator just works out of the box!

Mutator GUI


Say good-bye to blind spots

By testing your tests, Mutator tells you exactly where they need work, so you can deploy with confidence.
Mutator supports Ruby, Java, JavaScript, PHP and more languages are on the way!

Java and Ruby



Detect deadlocks, race conditions and more!

Mutator is ideal for concurrent Java projects!
Mutator helps you create tests that detect concurrency bugs before you release your applications.

Mutator for concurrent Java

Mutator for concurrent Java


Who is using Mutator?


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