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

/
/
gui

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"(http:\/\/\s*|https:\/\/\s*|ftp:\/\/\s*)?(www\s*)?(?(1)([.]\s*))?(?(2)([.]\s*))?([a-zA-Z0-9.-]{2,256})(\s*[.]\s*)(ru|pl|kz|by|ua|com|in|pt|br|co.uk)(?![a-zA-Z])([?|#]{1}[=&#a-zA-Z0-9]{2,128})?" test_str = ("http:// www . alga-deweloper . pl\n" "TIRA UM: Ńąm iuvaret tus electram. Tempor http://www.google.com in eam, ut dictas disputando vim.\n" "NO TIRA: kuchnia.Na impedit ne, cu pri vęri nostro, mel ut integre praesent dissentias.\n" "TIRA UM: Ceteros inćorruptę google.com?sad=asd id, saępe ńullam vix ut.\n" "TIRA UM: Eam ut ępićurei adólesćens. Nam ąd sumo agąm. Vis te dicam https://www.google.com.\n" "TIRA UM: Has ęa, ei cóngue tęmpóribus comprehęnsam http://asdasd asdas da www.amazon.co.uk.\n" "NÃ TIRA: No nónumy doćtus sd.asd.comia uma pizza.nan asjJ.domain djJ.co asd.uk, altęra cónśetetur ut.\n" "SECRETO: Hinc expetenda ocurreret at has. Ex eum ętiam http:// asdasdasd . com Cu vix.\n" "SECRETO: Hinc expetenda ocurreret at has. Ex eum ętiam www . asdasdasd . com Cu vix.\n" "SECRETO: http:// www . alga-deweloper . pl sdsdfsdfsdf\n" "NÃ TIRA: Altęra cónśetetur ut ?asd=asdd asdasd sdfsdfsdfsdf.\n" "TIRA UM: Ceteros inćorruptę http://www.google6.com#sdfsdf id, saępe ńullam vix ut.\n" "TIRA UM: Ceteros inćorruptę http://www.google6.com?asdads=asd&asasd=sdasd#sdfsdf id, ńullam vix ut.\n" "TIRA UM: Altęra cónśetetur www.donet.come sdffd. domain . com asdasd\n" "TIRA UM: Altęra cónśetetur www.donet.come sdffd. www . aasd . com asdasd\n" "TIRA UM: http:// www . alga-deweloper . pl") matches = re.finditer(regex, test_str, re.UNICODE | re.IGNORECASE) 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