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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"^<row Id=\"([^\"]*)\" PostTypeId=\"([^\"]*)\" ParentId=\"([^\"]*)\" CreationDate=\"([^\"]*)\" Score=\"([^\"]*)\" Body=\"([^\"]*)\" OwnerUserId=\"([^\"]*)\" LastEditorUserId=\"([^\"]*)\" LastEditorDisplayName=\"([^\"]*)\" LastEditDate=\"([^\"]*)\" LastActivityDate=\"([^\"]*)\" CommentCount=\"([^\"]*)\"?.*$>") test_str = "<row Id=\"1394\" PostTypeId=\"2\" ParentId=\"1390\" CreationDate=\"2008-08-04T16:38:03.667\" Score=\"16\" Body=\"&lt;p&gt;Not sure how credible &lt;a href=&quot;http://www.builderau.com.au/program/windows/soa/Getting-started-with-Windows-Server-2008-Core-edition/0,339024644,339288700,00.htm&quot; rel=&quot;nofollow noreferrer&quot;&gt;this source is&lt;/a&gt;, but:&lt;/p&gt;&#xA;&#xA;&lt;blockquote&gt;&#xA; &lt;p&gt;The Windows Server 2008 Core edition can:&lt;/p&gt;&#xA; &#xA; &lt;ul&gt;&#xA; &lt;li&gt;&lt;p&gt;Run the file server role.&lt;/p&gt;&lt;/li&gt;&#xA; &lt;li&gt;&lt;p&gt;Run the Hyper-V virtualization server role.&lt;/p&gt;&lt;/li&gt;&#xA; &lt;li&gt;&lt;p&gt;Run the Directory Services role.&lt;/p&gt;&lt;/li&gt;&#xA; &lt;li&gt;&lt;p&gt;Run the DHCP server role.&lt;/p&gt;&lt;/li&gt;&#xA; &lt;li&gt;&lt;p&gt;Run the IIS Web server role.&lt;/p&gt;&lt;/li&gt;&#xA; &lt;li&gt;&lt;p&gt;Run the DNS server role.&lt;/p&gt;&lt;/li&gt;&#xA; &lt;li&gt;&lt;p&gt;Run Active Directory Lightweight Directory Services.&lt;/p&gt;&lt;/li&gt;&#xA; &lt;li&gt;&lt;p&gt;Run the print server role.&lt;/p&gt;&lt;/li&gt;&#xA; &lt;/ul&gt;&#xA; &#xA; &lt;p&gt;The Windows Server 2008 Core edition cannot:&lt;/p&gt;&#xA; &#xA; &lt;ul&gt;&#xA; &lt;li&gt;&lt;p&gt;Run a SQL Server.&lt;/p&gt;&lt;/li&gt;&#xA; &lt;li&gt;&lt;p&gt;Run an Exchange Server.&lt;/p&gt;&lt;/li&gt;&#xA; &lt;li&gt;&lt;p&gt;Run Internet Explorer.&lt;/p&gt;&lt;/li&gt;&#xA; &lt;li&gt;&lt;p&gt;Run Windows Explorer.&lt;/p&gt;&lt;/li&gt;&#xA; &lt;li&gt;&lt;p&gt;Host a remote desktop session.&lt;/p&gt;&lt;/li&gt;&#xA; &lt;li&gt;&lt;p&gt;Run MMC snap-in consoles locally.&lt;/p&gt;&lt;/li&gt;&#xA; &lt;/ul&gt;&#xA;&lt;/blockquote&gt;&#xA;\" OwnerUserId=\"91\" LastEditorUserId=\"1\" LastEditorDisplayName=\"Jeff Atwood\" LastEditDate=\"2008-08-27T13:02:50.273\" LastActivityDate=\"2008-08-27T13:02:50.273\" CommentCount=\"1\" /> " matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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