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

/
/
img

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"^(?!\d\d?[ex]\d\d?)(?:\[(?:[-\w\s]+)*\] )?(.*?)[-_. ]?(?:[\{\(\[]?(?:dvdrip|[-._\b]ita|[-._\b]eng|xvid| cd\d|dvdscr|\w{1,5}rip|divx|\d+p|\d{4}).*?)?\.([\w]{2,3})$" test_str = ("22. Non Puoi Sempre Dire Quello Kent Ti Pare.avi\n" "6x13 - Una festa spettacolare.mkv\n" "After earth.avi\n" "Capitan America Il Primo Vendicatore 480p.mkv\n" "Dylan Dog 2010 Ac3.avi\n" "FUMETTOLOGY - 11 - PUNTATA SPECIALE.by.IperB.mkv\n" "Guida galattica per autostoppisti [BDrip 720p ITA-ENG sub ITA-ENG].mkv\n" "Hook - Capitan Uncino (1991).avi\n" "Kick Ass 2.avi\n" "Lemony Snicket - Una serie di sfortunati eventi 2004.avi\n" "Monty Python e il Sacro Graal.avi\n" "Pacific_Rim_2004_BdRip_1080p_ITA_ENG_ANONIMO_CREW.mkv\n" "Pompeii.2014.iTALiAN.DTS.Dual.1080p.BluRay.x264-TRtD_TeaM.mkv\n" "Ralph Spaccatutto.avi\n" "Red Hot Chili Simpson.avi\n" "RobinHood-UnUomoInCalzamaglia.ENG.srt\n" "The.Lego.Movie.2014.iTALiAN.AC3.DUAL.1080p.BluRay.x264-TrTd_TeaM.mkv\n" "The.Pagemaster.1994.1080p.BluRyMux.by.gemini9669.mkv\n" "Tom.&.Jerry.Avventure.Giganti.Giant.Adventure.2013.DVDRip.ITA.AC3.ENG.Mp3-MLN.avi\n" "Tron 480p.mkv\n" "Viaggi Spazio - Temporali.avi\n" "Vite Aliene.avi\n" "[DivX - ITA] The Simpson - Natale con i Simpsons 2003.avi\n" "[SUB ITA] Monty Python e il Sacro Graal.srt\n" "[Sub ENG] Monty Python e il Sacro Graal.srt\n" "codeschool_1322.mp4\n" "corto.avi\n" "film xvid.ENG.srt\n" "[rec].mp4\n" "recita.mp4\n" "regeng.flv") matches = re.finditer(regex, test_str, re.IGNORECASE | re.MULTILINE) 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