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

/
/
Uis

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 = "<\\!--\\[if\\s+lt\\s+IE\\s+\\d][^>]*>(.*)<\\!\\[endif\\]-->"; final String string = "\n\n" + "rwerwerw\n" + "<!--[if lt IE 9]>\n" + " <script src=\"https://oss.maxcdn.com/html5shiv/3.7.2/html5shiv.min.js\"></script>\n" + " <script src=\"https://oss.maxcdn.com/respond/1.4.2/respond.min.js\"></script>\n" + "<![endif]-->\n" + "rwerwerwerwe\n\n" + " <script type=\"text/javascript\">\n" + "jQuery(window).on('load', function() {\n" + " new JCaption('img.caption');\n" + " });\n" + "if (typeof RokBoxSettings == 'undefined') RokBoxSettings = {pc: '100'};\n" + "jQuery(document).ready(function()\n" + " {\n" + " jQuery('.hasTooltip').tooltip({\"html\": true,\"container\": \"body\"});\n" + " });\n" + " jQuery(document).ready(function (){\n" + " jQuery('.minicolors').each(function() {\n" + " jQuery(this).minicolors({\n" + " control: jQuery(this).attr('data-control') || 'hue',\n" + " position: jQuery(this).attr('data-position') || 'right',\n" + " theme: 'bootstrap'\n" + " });\n" + " });\n" + " });\n" + " \n\n" + " jQuery(function(){\n" + " new JVMenu('#',{\n" + " main: {\n" + " delay: 300,\n" + " duration: 300,\n" + " effect: 'fade',\n" + " easing: 'linear'\n" + " },\n" + " sub: {\n" + " delay: 300,\n" + " duration: 300,\n" + " effect: 'slide',\n" + " easing: 'linear'\n" + " },\n" + " responsive: 992\n" + " });\n" + " })\n" + " \n" + "jQuery(function(){new JVTop();});\n" + "jQuery(function($){ });\n" + " </script>\n\n\n\n\n" + "<!--[if lt IE 9]>\n" + " <script src=\"https://oss.maxcdn.com/html5shiv/3.7.2/html5shiv.min.js\"></script>\n" + " <script src=\"https://oss.maxcdn.com/respond/1.4.2/respond.min.js\"></script>\n" + "<![endif]-->\n"; final Pattern pattern = Pattern.compile(regex, Pattern.UNICODE_CHARACTER_CLASS | Pattern.CASE_INSENSITIVE | Pattern.DOTALL); 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