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

Generated Code

const regex = new RegExp('(?:(?<=^)|(?<=\\s))(?:(?:ht|f)tps?://)?(?!\\d+\\.)((?:[^\\W_]|-)[^\\W_]*(?:-[^\\W_]*)*(?:\\.(?:[^\\W_]|-)[^\\W_]*(?:-[^\\W_]*)*)*\\.[^\\W_][^\\W_]*)(?:\\s|$)', 'g') const str = `IP Address: 93.114.205.169 0.0.0.0 0.0.0.0 10.10.10.10 99.99.99.99 199.199.199.199 255.255.255.255 256.256.256.256 02.02.02.02 111.222.13.255 1.2.3.4 1.2.3.4.5 11.22.33.44 11.22.33.44.55 255.0.1.254 255.0.1.254 In a text 255.0.1.254 there is an IP address In a text 10.10.10.10 there is an IP address In a text 93.114.205.169 there is an IP address Domain: example.com https://sub5-7.example.com/ https://sub5-7.example.com sub.sub2.example.com www.example.com https://sub.example.com http://example.com ftp://sub.mit-example222.com In a text www.example.com there is an domain. In a text https://sub5-7.example.com there is an domain. In a text www.example.com there is an domain. URL 93.114.205.169/path example.com/path sub.example.com/path 93.114.205.169/path https://sub5-7.example.com/ http://example.com/ example.com/ sub.example.com/ www.--example.com/ www.examp--le.com/ www.example.co/ www.example.c/ example.com/path sub.example.com/path sub.example.com/path sub.example.com/path sub.example.com/path/path/path/p/a/q/1\$%h sub.example.com/path/path/path/p/a/q/1\$%1fh sub.example.com/path/path/%aa%1f%3dpath/p/a/q/1\$%1fh https://sub.example.com/path/path http://sub.example.com/path/path http://something.com/#\$SLJFHsdq32908432098=!~abc In a text example.com/path there is an URL path. In a text www.example.com/path there is an URL path. In a text www.blog.example.com/path there is an URL path. In a text sub.example.com/paththere is an URL path. In a text sub.example.com/path/path/path/p/a/q/1\$%h there is an URL path. In a text sub.example.com/path/path/path/p/a/q/ there is an URL path. `; // 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