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"Subject:\n\s+Security ID:[^\n]+\n\s+Account Name:\s+(?<account_creator>[^\n]+)", flags=re.MULTILINE) test_str = ("6/6/19\n" "9:27:22.000 AM \n" "06/06/2019 09:27:22 AM\n" "LogName=Security\n" "SourceName=Microsoft Windows security auditing.\n" "EventCode=4720\n" "EventType=0\n" "Type=Information\n" "ComputerName=CPMASNAAD03.na.cintas.com\n" "TaskCategory=User Account Management\n" "OpCode=Info\n" "RecordNumber=5472484169\n" "Keywords=Audit Success\n" "Message=A user account was created.\n\n" "Subject:\n" " Security ID: \"xxxxxxxxx\"\n" " Account Name: Account Creator\n" " Account Domain: xxxxx\n" " Logon ID: xxxxxxx\n\n" "New Account:\n" " Security ID: \"xxxxxx\"\n" " Account Name: Account Created\n" " Account Domain: xxxxxxx\n\n" "Attributes:\n" " SAM Account Name: xxxxxxxx\n" " Display Name: User\n" " User Principal Name: -\n" " Home Directory: -\n" " Home Drive: -\n" " Script Path: -\n" " Profile Path: -\n" " User Workstations: -\n" " Password Last Set: <never>\n" " Account Expires: <never>\n" " Primary Group ID: 513\n" " Allowed To Delegate To: -\n" " Old UAC Value: 0x0\n" " New UAC Value: 0x11\n" " User Account Control: \n" " Account Disabled\n" " 'Normal Account' - Enabled\n" " User Parameters: -\n" " SID History: -\n" " Logon Hours: <value not set>\n\n" "Additional Information:\n" " Privileges") 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