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"<script(?:\s+(?>\"[\S\s]*?\"|'[\S\s]*?'|(?:(?!\/>)[^>])?)+)?\s*>[\S\s]*?http:\/\/cdn\.walkme\.com\/users[\S\s]*?<\/script\s*(?=>)>") test_str = ("<!DOCTYPE html>\n" "<html lang=\"en\" dir=\"ltr\" class=\"client-nojs\">\n" "<head>\n" "<meta charset=\"UTF-8\" />\n" "<title>International English Language Testing System - Wikipedia, the free encyclopedia</title>\n" "<meta name=\"generator\" content=\"MediaWiki 1.25wmf2\" />\n" "<script type=\"text/javascript\">(function() {var walkme = document.createElement('script'); walkme.type = 'text/javascript'; walkme.async = true; walkme.src='http://cdn.walkme.com/users/cb643dab0d6f4c7cbc9d436e7c06f719/walkme_cb643dab0d6f4c7cbc9d436e7c06f719.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(walkme, s); window._walkmeConfig = {smartLoad:true}; })();</script>\n" "<link rel=\"alternate\" href=\"android-app://org.wikipedia/http/en.m.wikipedia.org/wiki/International_English_Language_Testing_System\" />\n" "<link rel=\"alternate\" type=\"application/x-wiki\" title=\"Edit this page\" href=\"/w/index.php?title=International_English_Language_Testing_System&amp;action=edit\" />\n") match = regex.search(test_str) if match: print(f"Match 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