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
No Match

/
/
gm

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"\b\sdark:[\w\-:]*\b" test_str = ("<template>\n\n" " <section class=\"bg-gray-50 dark:bg-gray-900\">\n" " <div class=\"flex flex-col items-center justify-center px-6 py-8 mx-auto md:h-screen lg:py-0\">\n" " <a href=\"#\" class=\"flex items-center mb-6 text-2xl font-semibold text-gray-900 dark:text-white\">\n" " <img class=\"w-8 h-8 mr-2\" src=\"https://flowbite.s3.amazonaws.com/blocks/marketing-ui/logo.svg\" alt=\"logo\">\n" " Flowbite \n" " </a>\n" " <div class=\"w-full bg-white rounded-lg shadow dark:border md:mt-0 sm:max-w-md xl:p-0 dark:bg-gray-800 dark:border-gray-700\">\n" " <div class=\"p-6 space-y-4 md:space-y-6 sm:p-8\">\n" " <h1 class=\"text-xl font-bold leading-tight tracking-tight text-gray-900 md:text-2xl dark:text-white\">\n" " Create and account\n" " </h1>\n" " <form class=\"space-y-4 md:space-y-6\" action=\"#\">\n" " <div>\n" " <label for=\"email\" class=\"block mb-2 text-sm font-medium text-gray-900 dark:text-white\">Your email</label>\n" " <input type=\"email\" name=\"email\" id=\"email\" class=\"bg-gray-50 border border-gray-300 text-gray-900 sm:text-sm rounded-lg focus:ring-primary-600 focus:border-primary-600 block w-full p-2.5 dark:bg-gray-700 dark:border-gray-600 dark:placeholder-gray-400 dark:text-white dark:focus:ring-blue-500 dark:focus:border-blue-500\" placeholder=\"name@company.com\" required=\"\">\n" " </div>\n" " <div>\n" " <label for=\"password\" class=\"block mb-2 text-sm font-medium text-gray-900 dark:text-white\">Password</label>\n" " <input type=\"password\" name=\"password\" id=\"password\" placeholder=\"••••••••\" class=\"bg-gray-50 border border-gray-300 text-gray-900 sm:text-sm rounded-lg focus:ring-primary-600 focus:border-primary-600 block w-full p-2.5 dark:bg-gray-700 dark:border-gray-600 dark:placeholder-gray-400 dark:text-white dark:focus:ring-blue-500 dark:focus:border-blue-500\" required=\"\">\n" " </div>\n" " <div>\n" " <label for=\"confirm-password\" class=\"block mb-2 text-sm font-medium text-gray-900 dark:text-white\">Confirm password</label>\n" " <input type=\"confirm-password\" name=\"confirm-password\" id=\"confirm-password\" placeholder=\"••••••••\" class=\"bg-gray-50 border border-gray-300 text-gray-900 sm:text-sm rounded-lg focus:ring-primary-600 focus:border-primary-600 block w-full p-2.5 dark:bg-gray-700 dark:border-gray-600 dark:placeholder-gray-400 dark:text-white dark:focus:ring-blue-500 dark:focus:border-blue-500\" required=\"\">\n" " </div>\n" " <div class=\"flex items-start\">\n" " <div class=\"flex items-center h-5\">\n" " <input id=\"terms\" aria-describedby=\"terms\" type=\"checkbox\" class=\"w-4 h-4 border border-gray-300 rounded bg-gray-50 focus:ring-3 focus:ring-primary-300 dark:bg-gray-700 dark:border-gray-600 dark:focus:ring-primary-600 dark:ring-offset-gray-800\" required=\"\">\n" " </div>\n" " <div class=\"ml-3 text-sm\">\n" " <label for=\"terms\" class=\"font-light text-gray-500 dark:text-gray-300\">I accept the <a class=\"font-medium text-primary-600 hover:underline dark:text-primary-500\" href=\"#\">Terms and Conditions</a></label>\n" " </div>\n" " </div>\n" " <button type=\"submit\" class=\"w-full text-white bg-primary-600 hover:bg-primary-700 focus:ring-4 focus:outline-none focus:ring-primary-300 font-medium rounded-lg text-sm px-5 py-2.5 text-center dark:bg-primary-600 dark:hover:bg-primary-700 dark:focus:ring-primary-800\">Create an account</button>\n" " <p class=\"text-sm font-light text-gray-500 dark:text-gray-400\">\n" " Already have an account? <a href=\"#\" class=\"font-medium text-primary-600 hover:underline dark:text-primary-500\">Login here</a>\n" " </p>\n" " </form>\n" " </div>\n" " </div>\n" " </div>\n" " </section>\n" "</template>\n") matches = re.finditer(regex, test_str, re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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