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

/
/
gmi

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"^[ABCEGHJKLMNPRSTVXY]\d[A-Za-z][ -]\d[A-Za-z]\d$" test_str = ("K1G\n" "----====\n" " K1G 6C9 \n" "Z1R p90\n" "w4t908\n\n" "w4r io9\n" "yt4 g7y\n\n\n" "K1G 6C9---\n" "K1G 6C9====\n" "K1G 6C9K1G 6C9\n" "K1G 6C9K1G 6C9K1G 6C9\n\n" "K1G 6C9slkdjfsdklfjsdkjfhsdf\n\n\n" "$[ABCEGHJKLMNPRSTVXY][0-9][ABCEGHJKLMNPRSTVWXYZ]{3} $[0-9][ABCEGHJKLMNPRSTVWXYZ][0-9]{3}\n\n" "K1G 6C9\n" "K1G6C9\n" "L7J 0A1\n" "L7J 0A2\n" "L7J 0A3\n" "L7J 0A4\n" "L7J 0A5\n" "L7J 0A6\n" "L7J 0A7\n" "L7J 2Y3\n" "L7J 2Y4\n" "L7J 2Y5\n" "L7J 2Y6\n" "L7J 2Y7\n" "L7J 2Y8\n" "L7J 2Y9\n" "L7J 2Z1\n" "L7J 2Z2\n" "N0G 0B5\n" "N0G 2X0\n\n" "W0G 0B5\n" "Y0G 2X0\n" "N0H 2T0\n" "Z0G 2X0") matches = re.finditer(regex, test_str, re.MULTILINE | 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