DEVELOPER TOOL / 63

Test a regex.
Catch the edge case.

Try a JavaScript regular expression against sample text, inspect capture groups, and preview a replacement without sending the text anywhere.

Pattern

Flags

Test text

Replacement preview

This tester uses the JavaScript RegExp engine. Patterns and test text stay in your browser; a maximum input size keeps accidental runaway patterns manageable.

QUICK ANSWERS

Which regex syntax is supported?

This page uses the regular expression syntax built into your browser's JavaScript engine, including flags such as g, i, m, s, u, and y.

Why are there no matches?

Check the pattern, flags, and whether you need a global g flag for repeated matches.

Test a regex.Catch the edge case.

Regular expression tester

Test a regex.
Catch the edge case.