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
No Match

/
/
gms

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"\[div(?:\sid=[\"|'](.*?)[\"|'])?(?:\sclass=[\"|'](.*?)[\"|'])?\](.*?)\[\/div\]" test_str = ("sdfsdfsd\n\n" "adafadfalkjdafdfa\n\n\n" "[div id=\"bla\" class=\"ups\"]some multiple line text[/div]\n\n" "[div class=\"bla\"]some multiple line text\n\n" "more lines\n" "[/div]\n\n" "[div id=\"first\"]\n" "some text\n" "[/div]\n\n" "Ovo ne bi trebalo da fatga\n\n\n" "[div id=\"bla\"]\n\n" "On the other hand, and in terms of severity, **DNS or NS takeovers** are less common but create the highest impact. An NS subdomain takeover is similar in principle to other types of subdomain takeovers. And due to the major role that NS records play in internet traffic, and the possibility of attackers chaining multiple attack vectors, an NS takeover can lead to severe implications for the target organization.\n\n\n" "*For our new blog series [Blast Radius][4], security professionals, researchers and experts deep dive into different attacks and vulnerabilities, explore how they can impact the entire internet ecosystem, and examine what they mean for organizations of all sizes, across all industries. To talk about the growing danger of DNS takeovers, we are joined by Patrik Hudák.*\n\n" "poop\n" "[/div]\n\n\n" "adfadfadfadfaf") matches = re.finditer(regex, test_str, re.MULTILINE | re.DOTALL) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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