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

/
/
gmx

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 = " (?(DEFINE)\n" + " (?<scheme>[a-z][a-z0-9+.-]*)\n" + " (?<userpass>([^:@\\/](:[^:@\\/])?@))\n" + " (?<domain>[a-z0-9]+(-[a-z0-9]+)*(\\.[a-z0-9]+(-[a-z0-9]+)*)+)\n" + " (?<ip>(([0-9a-fA-F]{1,4}:){7,7}[0-9a-fA-F]{1,4}|([0-9a-fA-F]{1,4}:){1,7}:|([0-9a-fA-F]{1,4}:){1,6}:[0-9a-fA-F]{1,4}|([0-9a-fA-F]{1,4}:){1,5}(:[0-9a-fA-F]{1,4}){1,2}|([0-9a-fA-F]{1,4}:){1,4}(:[0-9a-fA-F]{1,4}){1,3}|([0-9a-fA-F]{1,4}:){1,3}(:[0-9a-fA-F]{1,4}){1,4}|([0-9a-fA-F]{1,4}:){1,2}(:[0-9a-fA-F]{1,4}){1,5}|[0-9a-fA-F]{1,4}:((:[0-9a-fA-F]{1,4}){1,6})|:((:[0-9a-fA-F]{1,4}){1,7}|:)|fe80:(:[0-9a-fA-F]{0,4}){0,4}%[0-9a-zA-Z]{1,}|::(ffff(:0{1,4}){0,1}:){0,1}((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])\\.){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])|([0-9a-fA-F]{1,4}:){1,4}:((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])\\.){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])))\n" + " (?<host>((?&domain)|(?&ip)))\n" + " (?<port>(:[\\d]{1,5}))\n" + " (?<path>([^?;\\#\\s]*))\n" + " (?<query>(\\?[^\\#;\\s]*))\n" + " (?<anchor>(\\#\\S*))\n" + " )\n" + " (?:^)?-\\ +((?:(?&scheme):\\/\\/)?(?&userpass)?(?&host)(?&port)?\\/?(?&path)?(?&query)?(?&anchor)?)(?:$|\\s+)"; final String string = "- WWW.TELEGRAM.COM\n\n" + "- WWW.c.COM\n" + "- t.mE/rrbot\n" + "- t.me/rrbot\n\n" + "Edit the Expression & Text to see matches. Roll over matches or the expression for details. Undo mistakes with ctrl-z. Save Favorites & Share expressions with friends or the Community. Explore your results with Tools. A full Reference & Help is available in the Library, or watch the video Tutorial.\n\n" + "Sample text for testing:\n" + "abcdefghijklmnopqrstuvwxyz ABCDEFGHIJKLMNOPQRSTUVWXYZ\n" + "0123456789 _+-.,!@#$%^&*();\\/|<>\"'\n" + "12345 -98.7 3.141 .6180 9,000 +42\n" + "555.123.4567 +1-(800)-555-2468\n" + "foo@demo.net bar.ba@test.co.uk\n" + "- www.demo.com - http://foo.co.uk/\n" + "- wwww.s.com/something?somethgin=a#asdfadfragment asdfasfsafds\n" + "http://regexr.com/foo.html?q=bar\n" + "https://mediatemple.net\n\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.COMMENTS); 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