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

/
/
g

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"(?<=<td>)(.*)(?=<\/tr>)" test_str = ("<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Strict//EN\" \"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd\">\n" "<html xmlns=\"http://www.w3.org/1999/xhtml\">\n" "<head>\n" "<title>HTML TABLE</title>\n" "</head><body>\n" "<table>\n" "<colgroup><col/><col/><col/><col/><col/><col/></colgroup>\n" "<tr><th>DisplayName</th><th>DisplayVersion</th><th>InstallDate</th></tr>\n" "<tr><td>Adobe Acrobat Reader DC</td><td>18.009.20050</td><td>20171130</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Adobe Flash Player 28 ActiveX</td><td>28.0.0.137</td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Adobe Flash Player 28 NPAPI</td><td>28.0.0.137</td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Bonjour</td><td>3.1.0.1</td><td>20160316</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Cisco WebEx Meetings</td><td></td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Citrix Receiver</td><td>14.1.200.13</td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Crystal Reports XI Release 2</td><td>11.5.8.82627</td><td>20131115</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>CutePDF Writer 3.0</td><td> 3.0</td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Dropbox</td><td>41.4.80</td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>EditPlus</td><td></td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Fiddler</td><td>2.4.9.4</td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Google Chrome</td><td>63.0.3239.132</td><td>20131209</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Intel(R) Network Connections 18.7.28.0</td><td>18.7.28.0</td><td>20131114</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>iTunes</td><td>12.3.2.35</td><td>20160316</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Java 8 Update 151</td><td>8.0.1510.12</td><td>20171110</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>MGTEK Help Producer</td><td>3.1.2236</td><td>20131212</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft .NET Framework 4.7</td><td>4.7.02053</td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft ASP.NET MVC 2</td><td>2.0.60926.0</td><td>20170711</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft LifeCam</td><td>3.60.253.0</td><td>20160415</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Office 2003 Web Components</td><td>12.0.6213.1000</td><td>20170913</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Office 365 Business - en-us</td><td>16.0.8730.2175</td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Report Viewer Redistributable 2008 SP1</td><td></td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Silverlight</td><td>5.1.50907.0</td><td>20170614</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft SQL Server 2008 R2 (64-bit)</td><td></td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft SQL Server 2008 R2 Books Online</td><td>10.50.1600.1</td><td>20131202</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft SQL Server 2008 R2 Native Client</td><td>10.52.4042.0</td><td>20150715</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft SQL Server 2008 R2 Policies</td><td>10.50.1600.1</td><td>20131202</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft SQL Server 2008 R2 Setup (English)</td><td>10.52.4042.0</td><td>20150715</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft SQL Server 2008 Setup Support Files </td><td>10.1.2731.0</td><td>20131202</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft SQL Server Browser</td><td>10.52.4000.0</td><td>20150715</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft SQL Server Compact 3.5 SP2 ENU</td><td>3.5.8080.0</td><td>20131202</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft SQL Server Compact 3.5 SP2 Query Tools ENU</td><td>3.5.8080.0</td><td>20131202</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft SQL Server System CLR Types (x64)</td><td>10.52.4000.0</td><td>20150715</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft SQL Server VSS Writer</td><td>10.52.4000.0</td><td>20150715</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Sync Framework Runtime v1.0 (x64)</td><td>1.0.1215.0</td><td>20131202</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Sync Services for ADO.NET v2.0 (x64)</td><td>2.0.1215.0</td><td>20131202</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Visio Professional 2010</td><td>14.0.7015.1000</td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Visual C++ 2005 Redistributable</td><td>8.0.61001</td><td>20140405</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Visual C++ 2005 Redistributable</td><td>8.0.50727.42</td><td>20150430</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Visual C++ 2008 Redistributable - x64 9.0.30729.17</td><td>9.0.30729</td><td>20140506</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Visual C++ 2008 Redistributable - x64 9.0.30729.4148</td><td>9.0.30729.4148</td><td>20140917</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Visual C++ 2008 Redistributable - x64 9.0.30729.6161</td><td>9.0.30729.6161</td><td>20140507</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Visual C++ 2008 Redistributable - x86 9.0.30729</td><td>9.0.30729</td><td>20160211</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Visual C++ 2008 Redistributable - x86 9.0.30729.4148</td><td>9.0.30729.4148</td><td>20140917</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Visual C++ 2008 Redistributable - x86 9.0.30729.6161</td><td>9.0.30729.6161</td><td>20131213</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Visual C++ 2010 x64 Redistributable - 10.0.40219</td><td>10.0.40219</td><td>20150212</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Visual C++ 2010 x86 Redistributable - 10.0.40219</td><td>10.0.40219</td><td>20150212</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Visual C++ 2012 Redistributable (x64) - 11.0.61030</td><td>11.0.61030.0</td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Visual C++ 2012 Redistributable (x86) - 11.0.61030</td><td>11.0.61030.0</td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Visual Studio 2008 Shell (integrated mode) - ENU</td><td>9.0.30729</td><td>20140515</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Visual Studio 2010 Tools for Office Runtime (x64)</td><td>10.0.50903</td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft Visual Studio Tools for Applications 2.0 - ENU</td><td>9.0.35191</td><td>20131206</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Microsoft WSE 2.0 SP3 Runtime</td><td>2.0.5050.0</td><td>20160415</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Mozilla Firefox 57.0.4 (x64 en-US)</td><td>57.0.4</td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Mozilla Maintenance Service</td><td>57.0.4.6577</td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>MSXML 4.0 SP2 (KB954430)</td><td>4.20.9870.0</td><td>20131202</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>MSXML 4.0 SP2 (KB973688)</td><td>4.20.9876.0</td><td>20131202</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>MSXML 4.0 SP2 Parser and SDK</td><td>4.20.9818.0</td><td>20160415</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>NVIDIA Graphics Driver 347.52</td><td>347.52</td><td>20150831</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>NVIDIA nView 146.33</td><td>146.33</td><td>20150831</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>NVIDIA WMI 2.20.0</td><td>2.20.0</td><td>20150831</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>OneLogin OTP</td><td>1.0.1</td><td>20160803</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Reservationless-Plus VoIP</td><td>5.15.11.061</td><td>20160122</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Safari</td><td>5.34.57.2</td><td>20131217</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>SAP Crystal Reports 2013 SP01</td><td>14.1.1.1036</td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Snagit 10</td><td>10.0.0</td><td>20131206</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Symantec Endpoint Protection</td><td>14.0.2332.0100</td><td>20170329</td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>TeamViewer 11</td><td>11.0.59518</td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>VLC media player</td><td>2.2.6</td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>WinRAR archiver</td><td></td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>WinZip</td><td> 9.0 SR-1 (6224)</td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Xerox Scan Assistant</td><td>1.04.32.00</td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "<tr><td>Xerox WorkCentre 3315</td><td></td><td></td><td>kratos.kcprod1.com</td><td>4104917a-93f2-46e5-941a-c4efd54504b7</td><td>True</td></tr>\n" "</table>\n" "</body></html>\n") matches = re.finditer(regex, test_str) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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 Python, please visit: https://docs.python.org/3/library/re.html