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

~
~
igx

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""" #opening tag \{(RAW|ACCESS|DWNLINK|MODL|\w+) #optional attributes (?> \{ ([^}]*) } )? } #optional text and closing tag (?: ( #text:= any char except "{", or a "{" not followed by /commandname [^{]*+ (?>\{(?!/?\1[{}])[^{]*)*? ) #closing tag \{/\1} )? """ test_str = ("<div class=\"blog-list-item blog\"><header class=\"entry-title\">\n" " <h1>Welcome to our website</h1>\n" " </header><article id=\"entry-72\" class=\"entry post-72 page et-bg-layout-dark et-white-bg\"><div class=\"jumbotron row\">\n" "<div class=\"col-md-8\">\n" "<ul>\n" "<li>You have a pending job on your neck?&hellip;</li>\n" "<li>Do your company need a website makeover ?&hellip;</li>\n" "<li>Or a competitive web application ? ?&hellip;</li>\n" "<li>Do you need a customized plugin, or a tweak ?&hellip;</li>\n" "<li>Maybe you want a personal website ?&hellip;</li>\n" "<li>Or a graphic for your new project ?&hellip;</li>\n" "</ul>\n" "<div class=\"bg-primary well\">\n" "<h4 class=\"text-center text-white shadow\">Track your project as we work it to perfection...</h4>\n" "</div>\n" "</div>\n" "<div class=\"pull-right col-md-4\">\n" "<h4 class=\"bg-primary text-white well\">Other services we offer</h4>\n" "{ACCESS{type=500}}\n" "<ul>\n" "<li>SEO work for an existing website or new</li>\n" "<li>Bulk SMS</li>\n" "<li>E-currency exchange</li>\n" "<li>Facebook AD</li>\n" "<li>Google AD</li>\n" "</ul>\n" "{/ACCESS}</div>\n" "{RAW{say=email,access=500}} {RAW} <a class=\"btn button large tall green\" href=\"client-area\">Place new Job now as we deliver at the quickest <em>reasonable time</em></a>{/RAW}</div></article></div>") matches = re.finditer(regex, test_str, re.IGNORECASE | re.VERBOSE) 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