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

/
/

Test String

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "3Dcache*:().*%252B"; final String string = "<li class=\"g\"><h3 class=\"r\"><a href=\"http://maps.google.com/maps?um=1&amp;ie=UTF-8&amp;fb=1&amp;gl=us&amp;cid=12546501552342514458&amp;q=Malheur+National+Forest&amp;sa=X&amp;ei=tsCpU7y-HM28oQSa9IIQ&amp;ved=0CBUQtQMwAA\"><div>Map for <b>Malheur National Forest</b></div></a></h3><div class=\"mlmcm\" style=\"margin:16px 0\"><a href=\"http://maps.google.com/maps?um=1&amp;ie=UTF-8&amp;fb=1&amp;gl=us&amp;cid=12546501552342514458&amp;q=Malheur+National+Forest&amp;sa=X&amp;ei=tsCpU7y-HM28oQSa9IIQ&amp;ved=0CBYQtgMwAA\"><img height=\"233\" src=\"/maps/vt/data=VLHX1wd2Cgu8wR6jwyh-km8JBWAkEzU4,6YhdV0BKWTh3M22uoHrEdeI_eUVZLHdlKYEtPFQ8P__WuSea3AFMDTBKDIzC2UNN2GnK4eVSnL54ZIUZDihddu9CI74my1jHESqjX7czgrXEHjDCIHFYymlYhBU\" style=\"border:0;padding:1px\" width=\"550\"/></a></div><h3 class=\"r\"><a href=\"/url?q=http://www.fs.usda.gov/malheur&amp;sa=U&amp;ei=tsCpU7y-HM28oQSa9IIQ&amp;ved=0CBgQFjAA&amp;usg=AFQjCNEd9QcHqk_lxZTz9AcslMsyLwA9XQ\"><b>Malheur National Forest</b> - Home - USDA Forest Service</a></h3><div class=\"s\"><div class=\"kv\" style=\"margin-bottom:2px\"><cite>www.fs.usda.gov/<b>malheur</b></cite><div class=\"am-dwn-arw-container\">‎<div aria-expanded=\"false\" aria-haspopup=\"true\" data-ved=\"0CBkQ7B0wAA\" onclick=\"google.sham(this);\" style=\"display:inline\" tabindex=\"0\"><span class=\"am-dwn-arw\"></span></div><div class=\"am-dropdown-menu\" role=\"menu\" style=\"display:none\" tabindex=\"-1\"><ul><li class=\"am-dropdown-menu-item\"><a class=\"am-dropdown-menu-item-text\" href=\"/url?q=http://webcache.googleusercontent.com/search%3Fq%3Dcache:0bqZkM4XQqIJ:http://www.fs.usda.gov/malheur%252BMalheur%2BNational%2BForest%26hl%3Den%26%26ct%3Dclnk&amp;sa=U&amp;ei=tsCpU7y-HM28oQSa9IIQ&amp;ved=0CBsQIDAA&amp;usg=AFQjCNHcxq8MhoHz9__jp8pwHUrw2RPqCQ\">Cached</a></li><li class=\"am-dropdown-menu-item\"><a class=\"am-dropdown-menu-item-text\" href=\"/search?ie=UTF-8&amp;q=related:www.fs.usda.gov/malheur+Malheur+National+Forest&amp;tbo=1&amp;sa=X&amp;ei=tsCpU7y-HM28oQSa9IIQ&amp;ved=0CBwQHzAA\">Similar</a></li></ul></div></div></div><span class=\"st\">The 1.7 million acre <b>Malheur National</b> For est is located in the Blue Mountains of <br>\n" + "Eastern Oregon. The diverse and beautiful scenery of the <b>forest</b> includes high ...</br></span><br><div style=\"margin-top:13px\"><table width=\"100%\"><tr><td style=\"padding-right:4px;padding-top:1px\" valign=\"top\" width=\"24\"><img src=\"/mapfiles/marker-noalpha.png\"/></td><td valign=\"top\" width=\"485\"><span style=\"vertical-align:top\">Canyon City, OR 97820<br style=\"display:block\"><span class=\"nobr\">(541) 575-3000</span></br></span></td><td style=\"padding-top:2px;padding-left:9px\" valign=\"top\"><div style=\"float:right\"><div class=\"star\" style=\"float:none\"><div style=\"width:0px\"> </div></div></div><div style=\"clear:both\"><a class=\"fl nobr\" href=\"/url?q=https://plus.google.com/105110280666932757061/about%3Fhl%3Den%26socfid%3Dweb:lu:unknown:localdetails%26socpid%3D1&amp;sa=U&amp;ei=tsCpU7y-HM28oQSa9IIQ&amp;ved=0CCAQ4gkwAA&amp;usg=AFQjCNEo8ifBqVIqKICfCb2t4c6TZYk5mA\">2 reviews</a></div></td></tr></table></div></br></div><table cellpadding=\"0\" cellspacing=\"0\" class=\"slk\" style=\"border-collapse:collapse;margin-top:1px\"><tr class=\"mslg\"><td style=\"padding-left:23px;vertical-align:top\"><div class=\"sld\"><h3 class=\"r\"><a class=\"sla\" href=\"/url?q=http://www.fs.usda.gov/contactus/malheur/about-forest/contactus&amp;sa=U&amp;ei=tsCpU7y-HM28oQSa9IIQ&amp;ved=0CCMQjBAwAQ&amp;usg=AFQjCNGjoBzfmSfSTCOzBNxBnOhKa28FUQ\">Contact Us</a></h3><div class=\"s st\" style=\"width:220px;overflow:hidden\">More information is available on individual Ranger District Office ...</div></div></td><td style=\"padding-left:7px;vertical-align:top\"><div class=\"sld\"><h3 class=\"r\"><a class=\"sla\" href=\"/url?q=http://www.fs.usda.gov/recmain/malheur/recreation&amp;sa=U&amp;ei=tsCpU7y-HM28oQSa9IIQ&amp;ved=0CCUQjBAwAw&amp;usg=AFQjCNEmTooI03G5kMNTyIVqgU8Cu822dg\">Recreation</a></h3><div class=\"s st\" style=\"width:220px;overflow:hidden\">The 1.7 million acre Malheur National Forest located in the ...</div></div></td></tr><tr class=\"mslg\"><td style=\"padding-left:23px;vertical-align:top\"><div class=\"sld\"><h3 class=\"r\"><a class=\"sla\" href=\"/url?q=http://www.fs.usda.gov/main/malheur/maps-pubs&amp;sa=U&amp;ei=tsCpU7y-HM28oQSa9IIQ&amp;ved=0CCcQjBAwAg&amp;usg=AFQjCNFuRB8FTFH1goZ5XStBRakys6JoIQ\">Maps &amp; Publications</a></h3><div class=\"s st\" style=\"width:220px;overflow:hidden\">Forest Service Topography Maps: These maps overlay Forest ...</div></div></td><td style=\"padding-left:7px;vertical-align:top\"><div class=\"sld\"><h3 class=\"r\"><a class=\"sla\" href=\"/url?q=http://www.fs.usda.gov/main/malheur/about-forest&amp;sa=U&amp;ei=tsCpU7y-HM28oQSa9IIQ&amp;ved=0CCkQjBAwBA&amp;usg=AFQjCNHSrG5pziXkX2tf50PdNo7qWMeT1A\">About the Forest</a></h3><div class=\"s st\" style=\"width:220px;overflow:hidden\">The Malheur National Forest in the Blue Mountains of Eastern ...</div></div></td></tr><tr><td colspan=\"2\" style=\"padding-left:28px;vertical-align:top\"><div style=\"padding-top:5px\"><a class=\"fl\" href=\"/search?ie=UTF-8&amp;q=+site:usda.gov+Malheur+National+Forest&amp;sa=X&amp;ei=tsCpU7y-HM28oQSa9IIQ&amp;ved=0CCoQrAM\">More results from usda.gov »</a></div></td></tr></table></li>"; final Pattern pattern = Pattern.compile(regex); 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