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"Group:\s+Security\s+ID:\s+[^\\]*\\(\S+(?: \S+)*)") test_str = ("<13>Jan 09 12:33:50 TESTSRV1 AgentDevice=WindowsLog AgentLogFile=Security PluginVersion=7.2.4.86 Source=Microsoft-Windows-Security-Auditing Computer=corp.devnet.com OriginatingComputer=TESTSRV1 User= Domain= EventID=4755 EventIDCode=4755 EventType=8 EventCategory=13826 RecordNumber=1244048130 TimeGenerated=1483983229 TimeWritten=1483983229 Level=0 Keywords=0 Task=0 Opcode=0 Message=A security-enabled universal group was changed. Subject: Security ID: CORP\\TESTUSR1 Account Name: TESTUSR1 Account Domain: CORP Logon ID: 0x220f7a57 Group: Security ID: CORP\\VirtualUsers Group Name: VirtualUsers Group Domain: CORP Changed Attributes: SAM Account Name: - SID History: - Additional Information: Privileges: -\n\n" "<13>Jan 09 12:33:50 TESTSRV1 AgentDevice=WindowsLog AgentLogFile=Security PluginVersion=7.2.4.86 Source=Microsoft-Windows-Security-Auditing Computer=corp.devnet.com OriginatingComputer=TESTSRV1 User= Domain= EventID=4755 EventIDCode=4755 EventType=8 EventCategory=13826 RecordNumber=1244048130 TimeGenerated=1483983229 TimeWritten=1483983229 Level=0 Keywords=0 Task=0 Opcode=0 Message=A security-enabled universal group was changed. Subject: Security ID: CORP\\TESTUSR1 Account Name: TESTUSR1 Account Domain: CORP Logon ID: 0x220f7a57 Group: Security ID: CORP\\VM Admins Group Name: VM Admins Group Domain: CORP Changed Attributes: SAM Account Name: - SID History: - Additional Information: Privileges: -\n" "Group: Security ID: CORP\\Some Strange Account Name:") 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