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

/
/
igm

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"^(?:(?!\b(eng|ita)\b).)*\K\beng\W+\w+\W+sub\s?ita\b" test_str = ("Lucifer S03e15 [XviD - Eng Mp3 - Sub Ita Eng] DLRip By Pir8 [CURA] Fede e Religioni\n" "Lucifer S03e01-08 [XviD - Eng Mp3 - Sub Ita Eng] DLRip By Pir8 [CURA] Fede e Religioni SEASON PREMIERE\n" "Young Sheldon S01e13 [SATRip 720p - H264 - Eng Ac3 - Sub Ita] HDTV by AVS\n" "Young Sheldon S01e08 [Mux 1080p - H264 - Ita Eng Ac3 - Sub Ita Eng] WEBMux Morpheus\n" "Young Sheldon S01e08 [Mux 1080p - H264 - Ita Eng Ac3 - Sub Ita Eng] WEBMux Morpheus\n" "Young Sheldon S01e14 [SATRip 720p - H264 - Eng Ac3 - Sub Ita] HDTV by AVS\n" "Lucifer S03e15 [XviD - Eng Mp3 - Sub Ita Eng] DLRip By Pir8 [CURA] Fede e Religioni\n" "Lucifer S03e16 [XviD - Eng Mp3 - Sub Ita Eng] DLRip By Pir8 [CURA] Fede e Religioni\n" "Lucifer S02e01-13 [XviD - Eng Mp3 - Sub Ita] DLRip by Pir8 [CURA] Fede e Religioni FULL \n" "Absentia S01e01-10 [Mux 1080p - H264 - Ita Eng Ac3 - Sub Ita Eng] By Morpheus\n" "The.X.Factor.UK.S14E01.720p.HDTV.x264-FTP[rartv]\n" "The.X.Factor.S14E15.Judges.Houses.1.720p.AMZN.WEBRip.DDP2.0.x264-NTb[rarbg]\n" "Face.Off.S12E07.1080p.WEB.x264-CookieMonster[rarbg]\n" "Lucifer S02e01 [BDMux 1080p - H264 - Ita Eng Ac3 - Sub Ita Eng NUEng] By Morpheus [CURA] Fede e Religioni\n" "Lucifer.S02E01.H264.BDMux.ITA.Ac3.ENG.Ac3.5.1.Subs.RoomCrew.mkv") 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