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

/
/
gumi

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 = "(?s)(?<=start).*?(?=end)"; final String string = "Match all characters between two strings with dotall mode to match across line breaks\n\n" + "Duis sem mi, rhoncus ut enim quis, ultricies posuere libero.\n" + "Etiam et euismod dolor, at ornare lorem.\n" + "Praesent iaculis pellentesque felis, sit amet interdum ex ultricies id.\n" + "Nam eu mattis nisi.\n" + "Sed et odio risus.\n" + "Proin fermentum in justo non consequat.\n" + "Pellentesque pellentesque augue sed erat porta gravida.\n" + "In a magna at metus suscipit sodales non eget massa.\n" + "Maecenas eu turpis non nisl semper ultricies.\n" + "Duis rhoncus imperdiet sapien, vitae posuere erat tempor id.\n" + "Vestibulum in enim fermentum purus tempor maximus tempus quis ex.\n" + "Maecenas vitae felis ac elit semper blandit.\n" + "Suspendisse neque eros, vestibulum nec ultrices at, sagittis eget ex.\n" + "Aenean feugiat libero nunc, sit amet commodo turpis tristique luctus.\n" + "Sed sodales diam at urna viverra, nec ultrices enim imperdiet.\n" + "startLorem ipsum dolor sit amet, consectetur adipiscing elit.\n" + "Nulla velit diam, vehicula eget nunc at, aliquet mattis velit.\n" + "Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos.\n" + "Nam quis sollicitudin augue.\n" + "Maecenas a auctor nibh.\n" + "Pellentesque aliquam nulla sit amet posuere laoreet.\n" + "Nunc lorem massa, vehicula ac vehicula ac, varius vel est.\n" + "Proin sed mattis dolor.\n" + "Cras quis enim non nisl ultrices rhoncus in ut nisl.\n" + "endCurabitur venenatis ullamcorper ullamcorper.\n" + "Praesent in mi non mi bibendum lobortis at vel est.\n" + "Mauris luctus varius justo, non rhoncus sem tristique quis.\n" + "Aenean ac metus commodo felis pharetra dapibus.\n" + "Integer hendrerit, enim ac varius sagittis, ipsum lacus euismod elit, sed sagittis tortor purus nec sapien.\n" + "Morbi luctus risus quam, nec imperdiet nibh pulvinar id.\n" + "Pellentesque pretium posuere ligula, id ullamcorper sapien placerat at.\n" + "Nulla mattis tristique nisi id ornare.\n" + "Cras at orci magna.\n" + "Praesent interdum id est vitae feugiat.\n" + "Praesent vulputate, tortor at eleifend venenatis, leo turpis malesuada mauris, non lobortis urna velit fringilla lacus."; final Pattern pattern = Pattern.compile(regex, Pattern.UNICODE_CASE | Pattern.MULTILINE | Pattern.CASE_INSENSITIVE); 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