Regular Expressions 101

Save & Share

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

r"
"
s

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"<script>.*?(var.*?;).*?</script>"; string input = @"<script><!-- var STATIC_BASE = '//cdn1.editmysite.com/'; var STYLE_PREFIX = 'wsite'; //--> </script> <script src='https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js'></script> <script src='//cdn2.editmysite.com/js/site/main.js?buildTime=1400799662'></script> <script>_W.relinquish && _W.relinquish()</script> <script type='text/javascript'><!-- (function(jQuery){ function initFlyouts(){initPublishedFlyoutMenus([{""id"":""408147401478827578"",""title"":""HOME"",""url"":""index.html"",""target"":""},{""id"":""852985120278826572"",""title"":""GET A DOMAIN"",""url"":""get-a-domain.html"",""target"":""},{""id"":""745935904556716097"",""title"":""SERVICES"",""url"":""services.html"",""target"":""},{""id"":""505441827833699923"",""title"":""MY ACCOUNT"",""url"":""my-account.html"",""target"":""},{""id"":""464549931862712377"",""title"":""ABOUT US"",""url"":""about-us.html"",""target"":""}],""408147401478827578"",""<li><a href='#'>{{title}}<\/a><\/li>"",'active',false)} if (jQuery) { if (jQuery.browser.msie && !window.flyoutMenusRefreshable) window.onload = initFlyouts; else jQuery(initFlyouts); }else{ if (Prototype.Browser.IE) window.onload = initFlyouts; else document.observe('dom:loaded', initFlyouts); } })(window._W && _W.jQuery) //--> </script> </head> <body class=' wsite-theme-light wsite-page-index'> <div id=""fb-root""></div> <script>(function(d, s, id) { var js, fjs = d.getElementsByTagName(s)[0]; if (d.getElementById(id)) return; js = d.createElement(s); js.id = id; js.src = ""//connect.facebook.net/en_US/sdk.js#xfbml=1&appId=109188665774734&version=v2.0""; fjs.parentNode.insertBefore(js, fjs); }(document, 'script', 'facebook-jssdk'));</script> <div id=""nav-fixed""> <div id=""nav-body""> <span style=""visibility:hidden"">Pwns.me</span> <ul class='wsite-menu-default'><li id='active'><a href='/'>HOME</a></li><li id='pg852985120278826572'><a href='/get-a-domain.html'>GET A DOMAIN</a></li><li id='pg745935904556716097'><a href='/services.html'>SERVICES</a></li><li id='pg505441827833699923'><a href='/my-account.html'>MY ACCOUNT</a></li><li id='pg464549931862712377'><a href='/about-us.html'>ABOUT US</a></li></ul> </div> </div> <div id=""pwns-logo""> <span style=""display:hidden;"" david=""gay""></span> </div> <div id=""content-body""> <div id=""titleImg""> <img src=""/files/theme/middlef.png""> </div> <div id=""que""> <ul> <li><a href=""about-us.html"">QUE?</a> </li> <li><a href=""get-a-domain.html"">SEEMS LEGIT</a> </li> </ul> </div> </div> <div id=""social""> <div class=""fb-like"" data-href=""http://pwns.me"" data-layout=""button"" data-action=""like"" data-show-faces=""false"" data-share=""false""></div><br><br> <a href=""https://twitter.com/share"" class=""twitter-share-button"" data-url=""http://pwns.me"" data-text=""Pwns.me - Awesome domains"" data-count=""none"" data-hashtags=""pwns"">Tweet</a> <script>!function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0],p=/^http:/.test(d.location)?'http':'https';if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src=p+'://platform.twitter.com/widgets.js';fjs.parentNode.insertBefore(js,fjs);}}(document, 'script', 'twitter-wjs');</script> </div> <div id=""myFooter""> Brought to you by Awesomness. </div> <div style=""display:none;""> <div><div class='wsite-elements wsite-footer'> <div><div class=""wsite-multicol""><div class='wsite-multicol-table-wrap' style='margin:0 -15px'> <table class='wsite-multicol-table'> <tbody class='wsite-multicol-tbody'> <tr class='wsite-multicol-tr'> <td class='wsite-multicol-col' style='width:50%;padding:0 15px'></td> <td class='wsite-multicol-col' style='width:50%;padding:0 15px'></td> </tr> </tbody> </table> </div></div></div> <div class=""weebly-footer"" style=""text-align:right;""><div style=""height:10px;overflow:hidden""></div> Proudly powered by <a href=""http://www.weebly.com/?utm_source=internal&utm_medium=footer&utm_campaign=2"" href=""_blank"">Weebly</a> <div style=""height:10px;overflow:hidden""></div></div></div> <script type='text/javascript'> <!-- if (document.cookie.match(/(^|;)\s*is_mobile=1/)) { var windowHref = window.location.href || ''; if (windowHref.indexOf('?') > -1) { windowHref += '&'; } else { windowHref += '?'; } document.write( ""&nbsp;&nbsp;&nbsp;&nbsp;"" + ""<a class='wsite-view-link-mobile' href='"" + windowHref + ""view=mobile'>Mobile Site</a>"" ); } "; RegexOptions options = RegexOptions.Singleline; Match m = Regex.Match(input, pattern, options); Console.WriteLine("'{0}' found at index {1}", m.Value, m.Index); } }

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 C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx