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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"(([(|\[](?P<series>[^)\]]*)[)|\]]))?((?P<author>.*[^\s][^\-])[\s]+-[\s]*)?(?P<title>[^(]*)([(|\[](?:[\s]*(?P<published>(([12][\d]{3,3})(?:(?!([^.\)\-a-zA-Z_]*(-+[^.\)a-zA-Z_]+)+)))))?)?[\s]*([,]?[\s]*(?P<publisher>[\s\w\s]*)[\s]*)?([,]?[\s]*(isbn:|isbn[-]?13:)?(?P<isbn>[0-9-]+))?[)|\]])?", flags=re.IGNORECASE | re.MULTILINE) test_str = ("(1958, Open Road d34234234, 978-1-4532-1730-6).epub\n" "(1958, Open Ro234ad , 9781-4532-o1730-6).epub\n" "(1958, Open Rosd234ad ).epub\n" "( 1958 ).epub\n" "(1958).epub\n" "( Open Road ).epub\n" "(Open road , 9234-1-4532-17300-9-6).epub\n" "(1234, 9234-1-4532-17300-9-6).epub\n" "(91886).epub\n" "(9186).epub\n" "(1186).epub\n\n" "title (1958, Open Road34234234, 978-1-4532-1730-6).epub\n" "(asdf) author, a2 - title ioiuoi-uyoiu (1958, Open Ro234ad , 9781-4532-1730-6).epub\n" "author, adf - title ioiuoi-uyoiu (1958, Open Rosd234ad ).epub\n" "author, adf - title ioiuoi-uyoiu ( 1958 ).epub\n" "author, adf - title ioiuoi-uyoiu (1958).epub\n" "author, adf - title ioiuoi-uyoiu ( Open Road ).epub\n" "(dddfasdfasdf) author666, a66df - title ioiuoi-uyoiu (Open road , 9234-1-4532-17300-9-6).epub\n" "author, adf - title ioiuoi-uyoiu (1234, 9234-1-4532-17300-9-6).epub\n" "author, adf - title ioiuoi-uyoiu (1234, 923416).epub\n" "author, adf - title ioiuoi-uyoiu ( 91886-8).epub\n" "author, adf - title ioiuoi-uyoiu ( 9186 ).epub\n" "author, adf - title ioiuoi-uyoiu ( 1186 ).epub\n" "(dddfasdfasdf) author666, a66df - title ioiuoi-uyoiu ( Open road , isbn:9234-1-4532-17300-9-6).epub\n" "(dddfasdfasdf) author666, a66df - title ioiuoi-uyoiu ( Open road , isbn13:9234-1-4532-17300-9-6).epub\n" "(dddfasdfasdf) author666, a66df - title ioiuoi-uyoiu ( Open road , isbn-13:9234-1-4532-17300-9-6).epub\n" "(dddfasdfasdf) author666, a66df - title ioiuoi-uyoiu ( Open road , 9234-1-4532-17300-9-6).epub") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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