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

/
/

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 = "<a.*<\\/a>"; final String string = "<dl>\n" + "<dd>[1] <a href=\"/wiki/Geb%C3%A4ude\" title=\"Gebäude\">Gebäude</a>, <a href=\"/wiki/R%C3%A4umlichkeit\" title=\"Räumlichkeit\">Räumlichkeit</a>, <a href=\"/wiki/Unterkunft\" title=\"Unterkunft\">Unterkunft</a>\n" + "</dd>\n" + "<dd>[2] die <a href=\"/wiki/Gemeinschaft\" title=\"Gemeinschaft\">Gemeinschaft</a> der <a href=\"/wiki/Mensch\" title=\"Mensch\">Menschen</a>, die unter einem Dach zusammen leben, wohnen oder arbeiten</dd>\n" + "<dd>[3] der <a href=\"/wiki/Unterhaltung\" title=\"Unterhaltung\">Unterhaltung</a> dienendes Gebäude</dd>\n" + "<dd>[4] <i><a href=\"/wiki/Astrologie\" title=\"Astrologie\">Astrologie</a>:</i> <a href=\"/wiki/Tierkreiszeichen\" title=\"Tierkreiszeichen\">Tierkreiszeichen</a>\n" + "</dd>\n" + "<dd>[5] <a href=\"/w/index.php?title=Herrscherhaus&amp;action=edit&amp;redlink=1\" class=\"new\" title=\"Herrscherhaus (Seite nicht vorhanden)\">Herrscherhaus</a>\n" + "</dd>\n" + "<dd>[6] <a href=\"/wiki/Firma\" title=\"Firma\">Firma</a>, <a href=\"/wiki/Unternehmen\" title=\"Unternehmen\">Unternehmen</a>\n" + "</dd>\n" + "<dd>[7] <a href=\"/wiki/scherzhaft\" title=\"scherzhaft\"><i>scherzhaft</i></a> <a href=\"/wiki/Freund\" title=\"Freund\">Freund</a>\n" + "</dd>\n" + "<dd>[8] <i><a href=\"/wiki/umgangssprachlich\" title=\"umgangssprachlich\">umgangssprachlich</a>:</i> Gehäuse der <a href=\"/wiki/Schnecke\" title=\"Schnecke\">Schnecke</a>\n" + "</dd>\n" + "<dd>[9] Gasthaus oder <a href=\"/wiki/Gastst%C3%A4tte\" title=\"Gaststätte\">Gaststätte</a>\n" + "</dd>\n" + "</dl>\n"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); if (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