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"^(((https|http):\/\/)?([a-z0-9@:%._\+~#=]{1,256}\.)+[a-z0-9:()]{1,20}+(\/[a-z0-9_():@.]+)*(\/)?((\?|#).*)?|(website_not_available))", flags=re.MULTILINE) test_str = ("http://foo.com/blah_blah\n" "http://foo.com/blah_blah/\n" "http://foo.com/blah_blah_(wikipedia)\n" "http://foo.com/blah_blah_(wikipedia)_(again)\n" "http://www.example.com/wpstyle/?p=364\n" "https://www.example.com/foo/?bar=baz&inga=42&quux\n" "http://✪df.ws/123\n" "xzcz\n" "xzcxzvcxzvxczc\n\n" "suva\n" "www.https//:fgdv.com\n" "test.https://www.xflowpay.com\n" "http://fr.wikipedia.org/wiki/%C3%89l%C3%A9phant\n" "www.exldfcsdf/dcsdfv\n" "http://userid:password@example.com:8080\n" "http://userid:password@example.com:8080/\n" "http://userid@example.com\n" "http://userid@example.com/\n" "http://userid@example.com:8080\n" "http://userid@example.com:8080/\n" "http://userid:password@example.com\n" "http://userid:password@example.com/\n" "http://142.42.1.1/\n" "http://142.42.1.1:8080/\n" "http://➡.ws/䨹\n" "http://www.mysite.com/myresumé.html\n" "http://foo.com/blah_(wikipedia)#cite-1\n" "http://foo.com/blah_(wikipedia)_blah#cite-1 \n" "http://code.google.com/events/#&product=browser\n" "http://foo.com/unicode_(✪)_in_parens\n" "http://foo.com/(something)?after=parens\n" "http://code.google.com/events/#&product=browser\n" "ftp://foo.bar/baz\n" "http://j.mp\n" "http://foo.bar/?q=Test%20URL-encoded%20stuff\n" "http://-.~_!$&'()*+,;=:%40:80%2f::::::@example.com \n" "http://1337.net\n" "http://a.b-c.de\n" "http://223.255.255.254\n" "https://foo_bar.example.com/\n\n" "https://regex101.com/\n\n\n" "http://\n" "http://.\n" "http://../\n" "http://##\n" "///a\n" "http:///a\n" "foo.com\n" "rdar://1234\n" "http:// shouldfail.com\n" "h://test\n" "http://foo.bar/foo(bar)baz quux\n" "http://10.1.1.255\n" "http://-a.b.co\n" "http://a.b--c.de/\n" "ftps://foo.bar/\n" "http://3628126748\n" "http://.www.foo.bar./\n" "http://www.foo.bar./\n" "http://.www.foo.bar/\n" "http://10.1.1.254\n" "fghfg") 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