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

const regex = /(?:['\*\?\x5c`][^\n\/]+\/|\/[^\/]+?['\*\?\x5c`]|\$[!#-\$\(\*\-0-9\?-\[_a-\{])/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?:[\'\\*\\?\\x5c`][^\\n\\\/]+\\\/|\\\/[^\\\/]+?[\'\\*\\?\\x5c`]|\\$[!#-\\$\\(\\*\\-0-9\\?-\\[_a-\\{])', 'gm') const str = `false_positive=do+you+want+a+pizza?+with+mozzarella/pomodoro? host=www.google.com;cd+/etc;/bin\$u/ca*+passwd host=www.google.com;cat\$@/etc\$@/passwd host=www.google.com;cd+/et*;/bi*\$u/ca*+passwd host=www.google.it;/bin/c*t\$u+/etc\$u/passwd host=www.google.it;/bin/cat\$u+/*tc\$u/passwd host=www.google.it;cd+/etc;/bin/c*t+passwd host=www.google.com;/bin/ca?+/et?/passwd host=www.google.com;cat+/etc/\${a}passwd host=www.google.com;cat+/etc/\$(echo)passwd host=www.google.com;cat+/etc/\`echo\`passwd host=www.google.com;cat+/etc\${a}/passwd host=www.google.com;cat+/etc\$(echo)/passwd host=www.google.com;cat+/etc\`echo\`/passwd host=www.google.com;cat+/etc/passwd\${a} host=www.google.com;cat+/etc/passwd\$(echo) host=www.google.com;cat+/etc/passwd\`echo\` host=www.google.com;ca?+/et?/pa??wd host=www.google.com;cd+etc/+ca?+passwd host=www.google.com;?at+/?tc/passwd host=www.google.com;c\\a\\t+/e\\t\\c/pa\\s\\swd host=www.google.com;cd+/etc;c\\at+p\\a\\sswd host=www.google.com;cd+/etc;c'at'+p'a'sswd host=www.google.com;c\$@at /et\$@c/pas\$@swd host=www.google.com;c\$!at /et\$!c/pas\$!swd host=www.google.com;c\$*at /et\$*c/pas\$*swd host=www.google.com;c\$?at /et\$?c/pas\$?swd host=www.google.com;c\$-at /et\$-c/pas\$-swd host=www.google.com;c\$_at /et\$_c/pas\$_swd host=www.google.com;c\$\$at /et\$\$c/pas\$\$swd`; // 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