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"\S+\d\.\d+", flags=re.MULTILINE) test_str = ("Internet Uplink FON 41.79.9.117 : Successful\n" "Microtik 194.201.253.246 : Successful\n" "Rooftop Switch 213.150.96.166: Successful\n\n" " TELNET TEST\n" " telnet mail.kenyaweb.com 25 : Connected to mail.kenyaweb.com. Escape character is '^]'. 220 mail.kenyaweb.com ESMTP Postfix\n" " telnet mail.kenyaweb.com 110: Connected to mail.kenyaweb.com. Escape character is '^]'. +OK POP3 ready\n\n" " MAIL SERVERS\n" " mail.kenyaweb.com 194.201.253.165 : Successful\n" " Relay.kenyaweb.com 194.201.253.124 : Successful\n" " pop.kenyaweb.com 194.201.253.11 : Successful\n" " hosting.kenyaweb.com 194.201.253.132 : Successful\n\n" " WEB SERVERS\n" "Web server 1 194.201.253.70 : Successful\n" "Web server 2 194.201.253.8 : Successful\n" "Web Server 3 194.201.253.5 : Successful\n" "sungura.kenyaweb.com 192.64.112.132: Successful\n" " \n\n" " DNS\n" " Linux.form-net.com 194.201.253.105 : Successful\n" " ns200.kenyaweb.com 194.201.253.186 : Successful\n" " ns201.kenyaweb.com 194.201.253.189 : Successful\n" " ns203.kenyaweb.com 63.250.47.221 : Successful\n\n" " BROWSE TEST\n" " www.kenyaweb.com http://www.kenyaweb.com : Successful\n" " www.yahoo.com http://www.yahoo.com : Successful\n" " www.google.com http://www.google.com : Successful\n\n" " MAIL TEST\n" " Mail.Kenyaweb to yahoo : Received\n" " Mail.Kenyaweb to gmail : Received\n" " Yahoo to Mail.Kenyaweb : Received\n" " Gmail to Mail.Kenyaweb : Received") 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