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

/
/
gs

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 = "\\/\\*(?!(\\<\\!\\[CDATA\\[)|(\\]\\]>))(.*?)\\*\\/"; final String string = "<script type=\"text/javascript\" src=\"//<?php echo SITE_CDN_STATIC_DOMAIN; ?>/src/js/lib.js?<?php echo CACHEBUST; ?>\"></script>\n" + "<?php /*<script type=\"text/javascript\" src=\"//<?php echo SITE_CDN_STATIC_DOMAIN; ?>/src/js/prod.js.php?<?php echo CACHEBUST; ?>\"></script> */ ?>\n" + "<script type=\"text/javascript\">\n" + "/*<![CDATA[*/ \n" + "updateBodyClassContext(); \n" + "cookieSetContext();\n\n" + "/* Run code on page load */\n" + "addEvent(window, 'load', function() \n" + "{\n" + " /**\n" + " *\n" + " * Example comment inside of \n" + " * CDATA\n" + " *\n" + " */\n" + " document.getElementById('emailm').focus();\n" + " if (location.href.indexOf('prereg=2') > -1) document.getElementById('prereg_email').focus();\n" + " addEvent(document.getElementById('prereg_form'), 'submit', function(e)\n" + " {\n" + " var e = (e) ? e : window.event, \n" + " regex_email = /^([a-z0-9])(([-a-z0-9._])*([a-z0-9_-]))*@([a-z0-9])(([a-z0-9-])*([a-z0-9]))+(\\.([a-z0-9])([-a-z0-9-])?([a-z0-9])+)+$/i;\n" + " if (this.prereg_email.value == '' \n" + " || !regex_email.test(this.prereg_email.value))\n" + " {\n" + " this.prereg_email.focus();\n" + " stopEvent(e);\n" + " }\n" + " });\n" + "}); \n" + "/*]]>*/\n" + "</script>\n" + "/* another comment for good measure */\n" + "/*and another\n" + "*/\n" + "/*another*/"; final Pattern pattern = Pattern.compile(regex, Pattern.DOTALL); 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