Regex Tester
Test regular expressions with live highlighting and capture groups. No uploads.
How does the regex tester work?
Enter a pattern, toggle the g, i,
m, and s flags, and paste in text to test
against it. Matches are highlighted inline as you type, with a running
match count and a breakdown of every match's capture groups below.
Invalid patterns show a clear error message instead of failing silently.
Everything runs on JavaScript's native RegExp engine in your
browser — your text and pattern are never sent anywhere.
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Did you know?
SonicNot all of Sonic 1 and Sonic 2's music was written by Masato Nakamura; the 1-Up jingle, the drowning warning theme, and the Chaos Emerald jingle were composed separately by Sega staffer Yukifumi Makino.
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