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

/
/
gs

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\\{v;<$_~|&A-Z]+$"; final String string = "<?php\n" + "define(aa,a.chr(ord(strtoupper(a))-ord(h)+ord(a)))and\n" + "define(bb,getopt(aa,[])[a])and\n" + "define(us,chr(ord(a)-true-true))and\n" + "(prin.t.(us).r)(\n" + "(arra.y.(us).chunk)(\n" + "(arra.y.(us).slice)(\n" + "(arra.y.(us).merge)(\n" + "range((ord(b)-ord(a)),bb)\n" + ",range((ord(c)-ord(a))*bb,(ord(b)-ord(a))+bb)\n" + ",range((ord(c)-ord(a))*bb+(ord(b)-ord(a)),((ord(c)-ord(a))+(ord(b)-ord(a)))*bb)\n" + ",range((ord(e)-ord(a))*bb,+(ord(b)-ord(a))+((ord(c)-ord(a))+(ord(b)-ord(a)))*bb)\n" + ",range((ord(e)-ord(a))*bb+(ord(b)-ord(a)),((ord(e)-ord(a))+(ord(b)-ord(a)))*bb)\n" + ",range(((ord(e)-ord(a))+(ord(c)-ord(a)))*bb,+(ord(b)-ord(a))+((ord(e)-ord(a))+(ord(b)-ord(a)))*bb)\n" + ",range(((ord(e)-ord(a))+(ord(c)-ord(a)))*bb+(ord(b)-ord(a)),((ord(e)-ord(a))-(ord(b)-ord(a)))*bb)\n" + ",range((ord(e)-ord(a))*bb,+(ord(b)-ord(a))+((ord(e)-ord(a))-(ord(b)-ord(a)))*bb)\n" + ",range((ord(e)-ord(a))*bb+(ord(b)-ord(a)),((ord(e)-ord(a))+(ord(b)-ord(a)))*bb)\n" + ",range(((ord(e)-ord(a))+(ord(c)-ord(a)))*bb,(ord(b)-ord(a))+((ord(e)-ord(a))+(ord(b)-ord(a)))*bb)\n" + ",range(((ord(e)-ord(a))+(ord(c)-ord(a)))*bb+(ord(b)-ord(a)),((ord(e)-ord(a))+(ord(c)-ord(a))+(ord(b)-ord(a)))*bb)\n" + ",range(((ord(e)-ord(a))+(ord(e)-ord(a)))*bb,(ord(b)-ord(a))+((ord(e)-ord(a))+(ord(c)-ord(a))+(ord(b)-ord(a)))*bb)\n" + ",range(((ord(e)-ord(a))+(ord(e)-ord(a)))*bb+(ord(b)-ord(a)),((ord(e)-ord(a))+(ord(e)-ord(a))+(ord(b)-ord(a)))*bb)\n" + ",range(((ord(q)-ord(a))-(ord(c)-ord(a)))*bb,(ord(b)-ord(a))+((ord(e)-ord(a))+(ord(e)-ord(a))+(ord(b)-ord(a)))*bb)\n" + ",range(((ord(q)-ord(a))-(ord(c)-ord(a)))*bb+(ord(b)-ord(a)),((ord(q)-ord(a))-(ord(b)-ord(a)))*bb)\n" + ")\n" + ",bb-bb,bb*bb\n" + "),bb)\n" + ")\n" + "?>"; final Pattern pattern = Pattern.compile(regex, Pattern.DOTALL); 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