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DEVELOPER UTILITY

Regex Tester

Test JavaScript regular expressions in a bounded Web Worker. Runs beyond the fixed deadline stop and are marked incomplete.

Example inputs

  • Match consecutive a charactersa+ baaa
Flags

Everything is processed only in this browser.

How it works

Test JavaScript regular expressions inside a bounded Worker.

Frequently asked questions

Can a regex freeze the page?

Tests run in a bounded Worker and stop after 250 ms.

Does a timeout mean no match?

No. A timeout is explicitly marked incomplete.