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]
  • Character class intersection
    [\w&&[^\d]]
  • 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"((https?|ftp):\/\/)?([a-z0-9+!*(),;?&=.-]+(:[a-z0-9+!*(),;?&=.-]+)?@)?([a-z0-9\-\.]*)\.(([a-z]{2,4})|([0-9]{1,3}\.([0-9]{1,3})\.([0-9]{1,3})))(:[0-9]{2,5})?(\/([a-z0-9+%-]\.?)+)*\/?(\?[a-z+&$_.-][a-z0-9;:@&%=+/.-]*)?(#[a-z_.-][a-z0-9+$%_.-]*)?", flags=re.IGNORECASE) test_str = ("rew ewrwe http://192.168.1.100:10/\n" "erewrw ew 192.168.1.100/1e rwerrewdsfsdf \n" "werew rrew we vk.com we ewr werw\n" " erewr http://vk.com/ ewrwe\n" "ewrew https://vk.com/ werew\n" "www.vk.com\n" "my age is : 60. and ...\n" "ятх.рф\n" "ыщьу ... dfggd\n\n" "Служу в армии?\n" "Еще целый год терпеть это убожество\n" "Ростом 1.90 см?\n" "За остальным в л.с :)\n\n" "http://test.test-75.1474.stackoverflow.com/\n" "https://www.stackoverflow.com\n" "https://www.stackoverflow.com/\n" "http://wwww.stackoverflow.com/\n" "http://wwww.stackoverflow.com\n\n\n" "http://test.test-75.1474.stackoverflow.com/\n" "http://www.stackoverflow.com\n" "http://www.stackoverflow.com/\n" "stackoverflow.com/\n" "stackoverflow.com\n\n" "http://www.example.com/etcetc\n" "www.example.com/etcetc\n" "example.com/etcetc\n" "user:pass@example.com/etcetc\n\n" "example.com/etcetc?query=aasd\n" "example.com/etcetc?query=aasd&dest=asds\n\n" "http://stackoverflow.com/questions/6427530/regular-expression-pattern-to-match-url-with-or-without-http-www\n" "http://stackoverflow.com/questions/6427530/regular-expression-pattern-to-match-url-with-or-without-http-www/\n" "my age is: 60. and ...") 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