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

Substitution
Processing...

Code Generator

Generated Code

$re = '/^(PageTitle = "([^"]*)")(.*)(<title>)([^<]*)(<\/title>)(.*)(<h1 id="page-title" class="font-36">)([^<]*)(<\/h1>)(.*)$/ms'; $str = '<!-- and this include too --> Must include all this too <% PageTitle = "Member Access" MetaDescription = "There are a number of degree and education paths that can lead an individual to a career in toxicology. This page is designed to provide those considering a career in toxicology with information on the profession, schooling needed, and more. The content of this page was originally developed as a printed publication called Resource Guide to Careers in Toxicology" Keywords = "SOT, Toxicology, Careers, Resource Guide" SocialImage = "http://209.183.221.233/images/sot_logo.png" SocialImageDescription = "SOT logo" SocialURL = "http://209.183.221.233/login.asp" %> <!doctype html> <html dir="ltr" lang="en"> <head> <meta charset="UTF-8"> <!-- Meta Tags --> <meta name="description" content="There are a number of degree and education paths that can lead an individual to a career in toxicology. This page is designed to provide those considering a career in toxicology with information on the profession, schooling needed, and more. The content of this page was originally developed as a printed publication called Resource Guide to Careers in Toxicology"> <meta name="keywords" content= "SOT, Toxicology, Careers, Resource Guide"> <meta name="viewport" content="width=device-width, initial-scale=1.0 shrink-to-fit=no"> <meta name="author" content="Society of Toxicology" /> <meta name ="robots" content="index" > <!-- Twitter and Facebook Social media tags --> <meta property="fb:app_id" content="309282950004135" /> <meta property="og:title" content="New Experiences in Toxicology Program" > <meta property="og:description" content="There are a number of degree and education paths that can lead an individual to a career in toxicology. This page is designed to provide those considering a career in toxicology with information on the profession, schooling needed, and more. The content of this page was originally developed as a printed publication called Resource Guide to Careers in Toxicology"> <meta property="og:image" content="http://209.183.221.233/images/sot_logo.png"> <meta property="og:url" content="http://209.183.221.233/education/st/next.asp"> <meta property="og:type" content="website" /> <!-- Non-Essential, But Recommended --> <meta property="og:site_name" content="Society of Toxicology"> <meta name="twitter:card" content="summary_large_image"> <meta name="twitter:image:alt" content= "SOT logo"> <meta name="twitter:creator" content="@SOToxicology" /> <!-- Non-Essential, But Required for Analytics --> <meta name="twitter:site" content="@SOToxicology"> <!-- Follow Facebook\'s recommendation of a minimum dimension of 1200x630 pixels and an aspect ratio of 1.91:1, but adhere to Twitter\'s file size requirement of less than 1MB.--> <!-- Page Title --> <title>New Experiences in Toxicology Program</title> <!-- #include virtual="/_includes/header_newsite_trt.asp" --> <div id="main" class="main-content"> <section class="inner-header divider layer-overlay overlay-dark-4" data-bg-img="/images/_interior-banners/About-banner.jpg" style="background-image: url(\'/images/_interior-banners/About-banner.jpg\'); "> <div class="container pt-30 pb-30"> <!-- Section Content --> <div class="section-content"> <div class="row"> <div class="col-md-6"> <h1 id="page-title" class="font-36">New Experiences in Toxicology Program</h1> <ol class="breadcrumb text-left mt-10 white"> <li class="active">New Experiences in Toxicology Program</li> </ol> </div> </div> </div> </div> </section> <!-- #include virtual="/_includes/social-buttons.asp" --> <!-- Indvidual Page Content Below --> <!-- #include virtual="/_global/SOTLogin.asp" --> <!-- Section: Paragraph ---> <section> <div class="container "> <div class="section-content"> <CENTER> <TABLE width=500> <TR> <TD height="0" width="226"></TD> <TD width="108"></TD> </TR> <TR> <TD height="211" valign="top"> <TABLE > <TR> <TD align=center height="185"> <noscript> Javascript not enabled. <BR>Membership functions are not available. </noscript> <% If Request.Cookies("sot-session-id") <> "" Then %> <h3>You are now logged in.<br>Please wait for the page to be redirected.</h3> <meta http-equiv=\'refresh\' content=\'1;url=/\'> <% End If %> </font></TD> </TR> </TABLE> </TD> <TD height="211"></TD> </TR> </TABLE> </CENTER> </div> <!-- /columns --> </div> </section> <!-- /section Full paragraph ends--> <!-- #include virtual="/_includes/footer.asp" --> '; $subst = "$1$3$4$2$6$7$8$2$10$11"; $result = preg_replace($re, $subst, $str); echo "The result of the substitution is ".$result;

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php