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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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" + " (?<void>br|img|area|base|col|command|embed|hr|input|keygen|link|meta|param|source|track|wbr|!DOCTYPE)\n" + " (?<any>[^<>]*+)\n" + ")\n\n" + "<div \\s class=\"card\">\n" + "(?P<pair> (?&any)\n" + " (:?\n" + " <(?P<v_tag>(?!\\/)(?&void))(?&any)> (?:(?&pair) | (?&any))*+ (<\\/(?P=v_tag)>)? |\n" + " <(?P<tag>(?!\\/)[^<> ]++)(?&any)> (?:(?&pair) | (?&any))*+ <\\/(?P=tag)>\n" + " ) (?&any)\n" + ")*\n" + "<\\/div>"; final String string = "<!DOCTYPE html>\n" + "<html>\n" + " <head>\n" + " <title>Example</title>\n" + " </head>\n" + " <body>\n" + " <div class=\"card-container\">\n" + " <div class=\"card\">\n" + " <h5>First MD Card</h5>\n" + " <img src=\"https://mdbootstrap.com/img/Photos/Horizontal/Nature/4-col/img%20(34).jpg\" alt=\"Card image cap\">\n" + " <p>\n" + " Lorem ipsum dolor sit amet consectetur adipisicing elit. Sapiente\n" + " fugiat accusamus excepturi rem temporibus nobis natus.\n" + " </p>\n" + " </div>\n" + " <div class=\"slider\">\n" + " <ul class=\"progress-bar\">\n" + " <li class=\"active\"></li>\n" + " <li></li>\n" + " <li></li>\n" + " </ul>\n" + " </div>\n" + " </div>\n" + " </body>\n" + "</html>\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