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

/
/
gmu

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 = "(?:([-‐‑‒–—―−⁃﹘﹣－])|(?:&(?:(?:#x(2d|201[0-5]|2212|2043|fe58|fe63|ff0d))|(?:#(45|820[89]|821[0123]|8722|8259|65112|65123|65293))|(hyphen|[nm]?dash|hybull|horbar|minus));?))"; final String string = "This captures an entity even if it lacks the ';', which is commonly encountered in the wild.\n\n" + "kbdash &#x2d; &#45; &#x2d &#45 -; -\n" + "dash &#x2010; &dash; &#8208; &#x2010 &#8208 ‐; ‐\n" + "hyphen &#x2011; &hyphen; &#8209; &#x2011 &#8209 ‑; ‑\n" + "figure &#x2012; &#8210; &#x2012 &#8210 ‒; ‒\n" + "em &#x2013; &ndash; &#8211; &#x2013 &#8211 –; –\n" + "en &#x2014; &mdash; &#8212; &#x2014 &#8212 —; —\n" + "horbar &#x2015; &horbar; &#8213; &#x2015 &#8213 ―; ―\n" + "minus &#x2212; &minus; &#8722; &#x2212 &#8722 −; −\n" + "hybull &#x2043; &hybull; &#8259; &#x2043 &#8259 ⁃; ⁃\n" + "fe58 &#xfe58; &#65112; &#xfe58 &#65112 ﹘; ﹘\n" + "fe63 &#xfe63; &#65123; &#xfe63 &#65123 ﹣; ﹣\n" + "ff0d &#xff0d; &#65293; &#xff0d &#65293 －; －\n\n" + "(?:([-‐‑‒–—―−⁃﹘﹣－])|(?:&(?:(?:#x(2d|201[0-5]|2212|2043|fe58|fe63|ff0d))|(?:#(45|820[89]|821[0123]|8722|8259|65112|65123|65293))|(hyphen|[nm]?dash|hybull|horbar|minus));?))"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.UNICODE_CASE); 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