Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gm

Test String

Code Generator

Language

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "(?!\\d\\d)(?![a-zA-Z]{2})(?:(?:>?[:;=%8BXx]['‘’]?[-o*,^っ]?(?:(?P<mouth>[()|Il])(?P=mouth)*|[\\/0\\]o\\\\D\\[PpSs<>\\{\\}CcOXx*3@ÞþbL&?$#]))|(?:[()\\\\\\{\\}\\/<\\[>\\]DOo0|SsXxlI*@q][-o*,]?['‘’]?[:=8;%Xx]<?))|(?P<head>\\()?(?:(?P<eye>[<>v*.^~=ಠ-])?[_.-](?P=eye)|[o0O][_.-][o0O]|>[_.-]?<)['‘’]?(?(head)\\))|xD|XD|XP|xP|DX|<3|\\^\\^|\\\\o\\/|o\\/|\\\\o"; final String string = ":-) :) :D :o) :] :3 :c) :> =] 8) =) :} :^) :っ)\n" + ":-D 8-D 8D x-D xD X-D XD =-D =D =-3 =3 B^D\n" + ":-))\n" + ">:[ :-( :( :-c :c :-< :っC :< :-[ :[ :{\n" + ";(\n" + ":-|| :@ >:(\n" + ":'-( :'(\n" + ":'-) :')\n" + "D:< D: D8 D; D= DX v.v D-':\n" + ">:O :-O :O :-o :o 8-0 O_O o-o O_o o_O o_o O-O\n" + ":* :^* ( '}{' )\n" + ";-) ;) *-) *) ;-] ;] ;D ;^) :-,\n" + ">:P :-P :P X-P x-p xp XP :-p :p \n" + "=p :-Þ :Þ :þ :-þ :-b :b d:\n" + ">:\\ >:/ :-/ :-. :/ :\\ =/ =\\ :L =L :S >.<\n" + ":| :-|\n" + ":$\n" + ":-X :X :-# :#\n" + "O:-) 0:-3 0:3 0:-) 0:) 0;^)\n" + ">:) >;) >:-)\n" + "}:-) }:) 3:-) 3:)\n" + "o/\\o ^5 >_>^ ^<_<\n" + "|;-) |-O\n" + ":-& :&\n" + "#-)\n" + "%-) %)\n" + "<:-|\n" + "ಠ_ಠ\n" + "\\o/\n" + "*\\0/*\n" + "(>_<)\n" + "~_~\n" + "-.-'\n" + "(=_=)\n\n\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); while (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(i)); } } } }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html