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?\:\/\/(?:[[:alnum:]]+\.)?[[:alnum:]]+\.(?:com|net|org)\/\S*)|(https?\:\/\/(?:\d{1,3}\.){3}\d{1,3}\/?(?:\:\d{0,6})?\/?)", flags=re.IGNORECASE | re.DOTALL | re.MULTILINE) test_str = ("Screen 0: minimum 320 x 200, current 3520 x 1080, maximum 8192 x 8192\n" "VGA-0 connected 1600x900+1920+180 (normal left inverted right x axis y axis) 443mm x 249mm\n" " 1600x900 60.00*+ 75.00 \n" " 1280x1024 75.02 70.00 60.02 \n" " 1440x900 59.89 \n" " 1280x800 59.81 \n" " 1152x864 75.00 \n" " 1280x720 59.97 \n" " 1024x768 75.08 70.07 60.00 \n" " 832x624 74.55 \n" " 800x600 72.19 75.00 60.32 56.25 \n" " 640x480 75.00 72.81 60.00 \n" " 720x400 70.08 \n" "LVDS connected (normal left inverted right x axis y axis)\n" " 1366x768 59.97 +\n" " 1280x720 59.86 \n" " 1152x768 59.78 \n" " 1024x768 59.92 \n" " 800x600 59.86 \n" " 848x480 59.66 \n" " 720x480 59.71 \n" " 640x480 59.38 \n" "HDMI-0 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 1150mm x 650mm\n" " 1360x768 60.02 +\n" " 1920x1080 60.00* 59.94 30.00 24.00 29.97 23.98 \n" " 1920x1080i 60.00 59.94 \n" " 1280x1024 60.02 \n" " 1280x720 60.00 59.94 \n" " 1024x768 60.00 \n" " 800x600 60.32 \n" " 720x480 60.00 59.94 \n" " 640x480 60.00 59.94 59.94 \n" " 720x400 70.08 \n\n" "/en/blog/title\n" "https://www.example.com/foo/?bar=baz&inga=42&quux\n" "http://✪df.ws/123\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://⌘.ws\n" "http://⌘.ws/\n" "http://foo.com/blah_(wikipedia)#cite-1\n" "http://foo.com/blah_(wikipedia)_blah#cite-1\n" "http://foo.com/unicode_(✪)_in_parens\n" "http://foo.com/(something)?after=parens\n" "http://☺.damowmow.com/\n" "http://code.google.com/events/#&product=browser\n" "http://j.mp\n" "ftp://foo.com/baz\n" "http://foo.bar/?q=Test%20URL-encoded%20stuff\n" "http://مثال.إختبار\n" "http://例子.测试\n" "http://उदाहरण.परीक्षा\n" "http://-.~_!$&'()*+,;=:%40:80%2f::::::@example.com\n" "http://1337.net\n" "http://a.b-c.de\n" "http://223.255.255.254\n\n" "SHOULD NOT MATCH:\n\n" "http://\n" "http://.\n" "http://..\n" "http://../\n" "http://?\n" "http://??\n" "http://??/\n" "http://#\n" "http://##\n" "http://##/\n" "http://foo.bar?q=Spaces should be encoded\n" "//\n" "//a\n" "///a\n" "///\n" "http:///a\n" "foo.com\n" "rdar://1234\n" "h://test\n" "http:// shouldfail.com\n" ":// should fail\n" "http://foo.bar/foo(bar)baz quux\n" "ftps://foo.bar/\n" "http://-error-.invalid/\n" "http://a.b--c.de/\n" "http://-a.b.co\n" "http://a.b-.co\n" "http://0.0.0.0 \n" "http://10.1.1.0\n" "http://10.1.1.255\n" "http://224.1.1.1\n" "http://1.1.1.1.1\n" "http://123.123.123\n" "http://3628126748\n" "http://.www.foo.bar/\n" "http://www.foo.bar./\n" "http://.www.foo.bar./\n" "http://10.1.1.1\n\n") 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