Pattern Utility
Regex Tester
Test expressions against real strings, toggle flags, and inspect every live match with highlighting.
Test String
Highlighted Matches
Match Results
0 matches
How to use this regex tester
Enter a pattern, choose the `g`, `i`, and `m` flags you want, and paste a test string. The preview highlights each match and lists every captured result so you can debug quickly.
Validate patterns
Check email, URL, slug, or token matchers before shipping them into production.
See all matches
Use global mode to inspect repeated matches across long multiline input.
Debug errors faster
Invalid syntax is surfaced immediately so you can correct patterns without context switching.
Regex Tester FAQ
Which flags are supported?
This tester includes `g`, `i`, and `m`, covering the most common browser regex workflows.
Does it highlight all matches?
Yes. When the global flag is enabled, every match is highlighted in the preview and listed below it.
Can I test multiline strings?
Yes. Enable the `m` flag when your anchors need to work across multiple lines.
Internal Links
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