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"(http|ftp|https):\/\/([\w\-_]+(?:(?:\.[\w\-_]+)+))([\w\-\.,@?^=%&amp;:/~\+#]*[\w\-\@?^=%&amp;/~\+#])?") test_str = ("http://myip.ms/browse/ip_ranges/1/ownerID/224218/ownerID_A/1/sort/1/asc/1#ip_ranges_tbl_top\n\n" "<script src=\"mraid.js\"></script>\n" "<img src=\"data:image/png,mone\" style=\"display: none\" onerror=\"\n" " (function(self) {\n" " setTimeout(function() {\n" " var creative = 'GetRich';\n" " var suffix = '';\n" " var country = 'om';\n" " var campaignId = 16492;\n" " var mediatorUrl = 'https://tags.mli.me';\n\n" " // --- ----\n" " var params={scriptId:'mone-tag-script-1',tagTimestamp: new Date().getTime(), tagId:(Math.floor(Math.random() * 10000))};\n" " var req = document.createElement('script');\n" " req.src = mediatorUrl + '/mediator/' + country + '/_/_/' + creative + '/452/' + campaignId + '?';\n" " req.id ='mone-tag-script-1';\n" " params.requestId = '%{${RequestID}}%';\n" " params.placement = '%{${Placement}}%';\n" " params.gclid = '%{${GoogleUserID}}%';\n\n" " if(!!suffix)\n" " params['x-suffix'] = suffix;\n" " for (var k in params) {\n" " req.src += '&amp;' + encodeURIComponent(k) + '=' + encodeURIComponent(params[k]);\n" " }\n" " if (!window.moneTags) window.moneTags = {};\n" " if (!window.moneTags.beacons) window.moneTags.beacons = {};\n" " window.moneTags.beacons[params.tagId] = {'transition':['%%CLICK_URL_ESC%%']};\n" " document.head.appendChild(req);\n" " }, 2000);\n" " })(this);\n" " \"/>\n" "<img src=\"https://imp.mli.me/api/track/impression?RequestID=%{${RequestID}}%&CreativeID=%{${CreativeID}}%&WinningPrice=%%WINNING_PRICE%%\" width=\"1\" height=\"1\">") 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