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

Generated Code

import re regex = re.compile((r"(?'gPatSyslogPRI'<\d+>)\n" r"(?'gPatMesgBody'.*)\n" r"(?'gPatMesgBodyMin'.*?)\n" r"(?'gPatSyslogNGHeader'\w{3}\s+\d{1,2}\s\d{1,2}:\d{1,2}:\d{1,2}\s\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})\n" r"(?'gPatMon'Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec|\d{1,2})\n" r"(?'gPatMonNum'\d{1,2})\n" r"(?'gPatDay'\d{1,2})\n" r"(?'gPatTime'\d{1,2}:\d{1,2}:\d{1,2})\n" r"(?'gPatYear'\d{2,4})\n" r"(?'gPatMSec'\d{1,3})\n" r"(?'gPatTimeMSec'\d{1,2}:\d{1,2}:\d{1,2}\.\d{1,3})\n" r"(?'gPatTimeZone'Z|UTC|[+-]\d{1,2}:?\d{2})\n" r"(?'gPatWeekday'Mon|Tue|Wed|Thu|Fri|Sat|Sun)\n" r"(?'gPatIpV4Dot'\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})\n" r"(?'gPatIpAddr'[0-9A-Fa-f]{0,4}(?::[0-9A-Fa-f]{0,4}){1,5}:(?:\d{1,3}(?:\.\d{1,3}){3}|[0-9A-Fa-f]{0,4}(?::[0-9A-Fa-f]{0,4})?)|\d{1,3}(?:\.\d{1,3}){3})\n" r"(?'gPatIpPort'\d{1,5})\n" r"(?'gPatProto'ftp|icmp|tcp|udp|http|ip|smb|smtp|snmp|others|FTP|ICMP|UDP|TCP|HTTP|IP|SMB|SMTP|SNMP|OTHERS)\n" r"(?'gPatFqdn'\w+[.\w+]+)\n" r"(?'gPatWord'\w+)\n" r"(?'gPatStr'[^\s]*)\n" r"(?'gPatHostName'[\w.-]+)\n" r"(?'gPatStrComma'[^,]*)\n" r"(?'gPatStrLeftParen'[^\(]*)\n" r"(?'gPatStrRightSB'[^\]]*)\n" r"(?'gPatInt'\d+)\n" r"(?'gPatSpace'\s+)\n" r"(?'gPatStrEndColon'[^:]*)\n" r"(?'gPatStrSQ'[^']*)\n" r"(?'gPatStrDQ'[^']*)\n" r"(?'gPatSentence'\w[\s+\w]*)"), flags=re.MULTILINE) test_str = "" 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