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

r"
"

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"/*.mkv" test_str = ("folder.jpg\n" "metadata\n" "Stargate SG-1 S01E01-E02 Children of the Gods.mkv\n" "Stargate SG-1 S01E03 The Enemy Within.mkv\n" "Stargate SG-1 S01E04 Emancipation.mkv\n" "Stargate SG-1 S01E05 The Broca Divide.mkv\n" "Stargate SG-1 S01E06 The First Commandment.mkv\n" "Stargate SG-1 S01E07 Cold Lazarus.mkv\n" "Stargate SG-1 S01E08 The Nox.mkv\n" "Stargate SG-1 S01E09 Brief Candle.mkv\n" "Stargate SG-1 S01E10 Thor's Hammer.mkv\n" "Stargate SG-1 S01E11 The Torment of Tantalus.mkv\n" "Stargate SG-1 S01E12 Bloodlines.mkv\n" "Stargate SG-1 S01E13 Fire and Water.mkv\n" "Stargate SG-1 S01E14 Hathor.mkv\n" "Stargate SG-1 S01E15 Singularity.mkv\n" "Stargate SG-1 S01E16 Cor-Ai.mkv\n" "Stargate SG-1 S01E17 Enigma.mkv\n" "Stargate SG-1 S01E18 Solitudes.mkv\n" "Stargate SG-1 S01E19 Tin Man.mkv\n" "Stargate SG-1 S01E20 There But For the Grace of God.mkv\n" "Stargate SG-1 S01E21 Politics (1).mkv\n" "Stargate SG-1 S01E22 Within the Serpent's Grasp (2).mkv\n") matches = re.search(regex, test_str) if matches: print ("Match was found at {start}-{end}: {match}".format(start = matches.start(), end = matches.end(), match = matches.group())) for groupNum in range(0, len(matches.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = matches.start(groupNum), end = matches.end(groupNum), group = matches.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