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Regex Studio
Build, test, and debug regular expressions in real time. Matches highlight instantly as you type, with detailed match info and a built-in quick reference.
Live matchingMatch highlightNamed groupsAll flagsQuick referenceNatural language ✦ ProFree forever
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Free plan: 10KB test string limit
test string0 matches
// drag a file here to load it
matches highlighted
// matches will be highlighted here
// quick reference — click to insert
.Any character
\dDigit 0-9
\wWord character
\sWhitespace
\DNon-digit
\WNon-word
\SNon-whitespace
^Start of string
$End of string
*0 or more
+1 or more
?0 or 1
{n,m}Between n and m
()Capture group
(?:)Non-capture group
(?<n>)Named group
[]Character class
[^]Negated class
|Alternation (or)
\bWord boundary
// common patterns — click to load
Email addresshello@devcrate.net
URLhttps://example.com
IPv4 address192.168.1.1
Phone number+1 (555) 123-4567
Date (YYYY-MM-DD)2026-03-25
Hex color#ff9c2a
UUIDxxxxxxxx-xxxx-4xxx
URL slugmy-page-title
JWT tokenxxxxx.yyyyy.zzzzz
Semver1.2.3
⚡ Live matching
Matches highlight in real time as you type — no button press needed.
🎨 Match highlighting
Every match is highlighted directly in your test string.
📋 Match details
See every match with its value, index position, and capture groups.
🏳 Flag toggles
Toggle global, case-insensitive, multiline, dotall, unicode, and sticky flags with one click.
📖 Quick reference
Built-in cheat sheet of common regex tokens. Click any token to insert it.
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