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

r"
"
g

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 = "<tr class='(.)'><td class='TR(.)'><a href='http://www\\.openstreetmap\\.org\\/\\?mlon=([-\\d\\.]+)&mlat=([-\\d\\.]+)&zoom=\\d+' target='_blank'><img src='img\\/flags\\/(\\w+)\\.gif' class='flag' width='\\d+px' title='(.+)' alt='\\w+' border='0'><\\/a>&nbsp;<a href='router_detail\\.php\\?FP=([a-zA-Z0-9]+)' target='_blank'>([^\\<]+)<\\/a><\\/td><td class='TDb'><table cellspacing='0' cellpadding='0' class='bwb'><tr title='([^']+)'><td class='bwr.?'><img src='img/bar/\\d+.png' width='\\d+px' height='15px' alt='\\d+'></td><td>&nbsp;<small>&nbsp;\\d+</small></td></tr></table></td><td class='TDc.?'>([^<]+)</td><td class='TDS'><table class='iT'><tr><td class='iT'>([^\\[]+)\\[<a class='who' href='/cgi\\-bin/whois.pl\\?ip=[\\d\\.]+' target='_blank'>([\\d\\.]+)</a>\\]</td>(<td><img src='img/status/Fast.png' title='Fast Server' alt='Fast Server'></td>)?(<td><img src='img/status/Exit.png' title='Exit Server' alt='Exit Server'></td>)?(<td><img src='img/status/Dir.png' title='Directory Server' alt='Directory Server'></td>)?(<td><img src='img/status/Guard.png' title='Guard Server' alt='Guard Server'></td>)?(<td><img src='img/status/Stable.png' title='Stable Server' alt='Stable Server'></td>)?(<td><img src='img/status/Authority.png' title='Authority Server' alt='Authority Server'/></td>)?<td><img src='[^']+' title='([^']+)' alt='[^']+'></td>(<td><img src='[^']+' title='([^']*)' alt='[^']*'></td>)?</tr></table></td><td class='TDc'>(<b>)?(\\d*)(</b>)?</td><td class='TDc'>(<b>)?([None\\d]*)(</b>)?</td><td class='(F\\d)'></td></tr>"; final String string = "<tr class='r'><td class='TRR'><a href='http://www.openstreetmap.org/?mlon=-0.1300&mlat=51.5000&zoom=6' target='_blank'><img src='img/flags/gb.gif' class='flag' width='18px' title='//GB' alt='GB' border='0'></a>&nbsp;<a href='router_detail.php?FP=dc358f29426fb682f96f37fb4f3538edbb94b3d4' target='_blank'>czu5kXA8zLE0</a></td><td class='TDb'><table cellspacing='0' cellpadding='0' class='bwb'><tr title='817 KBs'><td class='bwr'><img src='img/bar/1.png' width='69px' height='15px' alt='817'></td><td>&nbsp;<small>&nbsp;817</small></td></tr></table></td><td class='TDcb'>3 d</td><td class='TDS'><table class='iT'><tr><td class='iT'>212.38.166.231 [<a class='who' href='/cgi-bin/whois.pl?ip=212.38.166.231' target='_blank'>212.38.166.231</a>]</td><td><img src='img/status/Fast.png' title='Fast Server' alt='Fast Server'></td><td><img src='img/status/Exit.png' title='Exit Server' alt='Exit Server'></td><td><img src='img/status/Dir.png' title='Directory Server' alt='Directory Server'></td><td><img src='img/status/Guard.png' title='Guard Server' alt='Guard Server'></td><td><img src='img/status/Stable.png' title='Stable Server' alt='Stable Server'></td><td><img src='img/os-icons/Linux.png' title='Tor 0.2.4.22 on Linux' alt='Tor 0.2.4.22 on Linux'></td></tr></table></td><td class='TDc'>9001</td><td class='TDc'>9030</td><td class='F0'></td></tr>\n" + "<tr class='r'><td class='TRr'><a href='http://www.openstreetmap.org/?mlon=-93.3084&mlat=37.2999&zoom=6' target='_blank'><img src='img/flags/us.gif' class='flag' width='18px' title='Springfield/Missouri/US' alt='US' border='0'></a>&nbsp;<a href='router_detail.php?FP=643b8a73713e2e948c5e3359d5bf5e4c8249aee2' target='_blank'>d00dstor</a></td><td class='TDb'><table cellspacing='0' cellpadding='0' class='bwb'><tr title='2 KBs'><td class='bwr'><img src='img/bar/1.png' width='1px' height='15px' alt='2'></td><td>&nbsp;<small>&nbsp;2</small></td></tr></table></td><td class='TDc'>13 h</td><td class='TDS'><table class='iT'><tr><td class='iT'>173-18-211-201.client.mchsi.com [<a class='who' href='/cgi-bin/whois.pl?ip=173.18.211.201' target='_blank'>173.18.211.201</a>]</td><td><img src='img/status/Dir.png' title='Directory Server' alt='Directory Server'></td><td><img src='img/os-icons/Linux.png' title='Tor 0.2.4.22 on Linux' alt='Tor 0.2.4.22 on Linux'></td></tr></table></td><td class='TDc'>9001</td><td class='TDc'>9030</td><td class='F0'></td></tr>\n" + "<tr class='r'><td class='TRr'><a href='http://www.openstreetmap.org/?mlon=15.5000&mlat=49.7500&zoom=6' target='_blank'><img src='img/flags/cz.gif' class='flag' width='18px' title='//CZ' alt='CZ' border='0'></a>&nbsp;<a href='router_detail.php?FP=fb2b4193f34aaa980d0e8c6ec2aa71417525f4b5' target='_blank'>d1n</a></td><td class='TDb'><table cellspacing='0' cellpadding='0' class='bwb'><tr title='1780 KBs'><td class='bwr1'><img src='img/bar/2.png' width='66px' height='15px' alt='1780'></td><td>&nbsp;<small>&nbsp;1780</small></td></tr></table></td><td class='TDcb'>2 d</td><td class='TDS'><table class='iT'><tr><td class='iT'>185.8.237.27 [<a class='who' href='/cgi-bin/whois.pl?ip=185.8.237.27' target='_blank'>185.8.237.27</a>]</td><td><img src='img/status/Fast.png' title='Fast Server' alt='Fast Server'></td><td><img src='img/status/Dir.png' title='Directory Server' alt='Directory Server'></td><td><img src='img/status/Guard.png' title='Guard Server' alt='Guard Server'></td><td><img src='img/status/Stable.png' title='Stable Server' alt='Stable Server'></td><td><img src='img/os-icons/Linux.png' title='Tor 0.2.4.22 on Linux' alt='Tor 0.2.4.22 on Linux'></td></tr></table></td><td class='TDc'>9001</td><td class='TDc'>9030</td><td class='F0'></td></tr>\n" + "<tr class='r'><td class='TRR'><a href='http://www.openstreetmap.org/?mlon=4.9167&mlat=52.3500&zoom=6' target='_blank'><img src='img/flags/nl.gif' class='flag' width='18px' title='Amsterdam/Noord-Holland/NL' alt='NL' border='0'></a>&nbsp;<a href='router_detail.php?FP=6ef897645b79b6cb35e853b32506375014de3621' target='_blank'>d6relay</a></td><td class='TDb'><table cellspacing='0' cellpadding='0' class='bwb'><tr title='383 KBs'><td class='bwr'><img src='img/bar/1.png' width='32px' height='15px' alt='383'></td><td>&nbsp;<small>&nbsp;383</small></td></tr></table></td><td class='TDcb'>22 d</td><td class='TDS'><table class='iT'><tr><td class='iT'>charles.d6.nl [<a class='who' href='/cgi-bin/whois.pl?ip=82.161.239.177' target='_blank'>82.161.239.177</a>]</td><td><img src='img/status/Fast.png' title='Fast Server' alt='Fast Server'></td><td><img src='img/status/Dir.png' title='Directory Server' alt='Directory Server'></td><td><img src='img/status/Guard.png' title='Guard Server' alt='Guard Server'></td><td><img src='img/status/Stable.png' title='Stable Server' alt='Stable Server'></td><td><img src='img/os-icons/Linux.png' title='Tor 0.2.4.22 on Linux' alt='Tor 0.2.4.22 on Linux'></td></tr></table></td><td class='TDc'>110</td><td class='TDc'><b>80</b></td><td class='F0'></td></tr>\n"; final Pattern pattern = Pattern.compile(regex); 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