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 = /.*\:\/\/(?:www.)?([^\/]+)(\/.+")/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('.*\\:\\\/\\\/(?:www.)?([^\\\/]+)(\\\/.+")', 'gm') const str = `<a href="https://nova.rambler.ru/search?query=Наталия%20Михайловна%20Дудинская&utm_source=search&utm_medium=enser&utm_campaign=self_promo&utm_content=search"> <a href="https://search.rambler.su/static/search/2852365218/css/main.min.css"> <a href="https://static.rambler.ru"> <a href="https://mail.rambler.ru/?utm_source=search&amp;utm_campaign=self_promo&amp;utm_medium=topline&amp;utm_content=mail"> <a href="//ssp.rambler.ru/capirs_async.js"> <a href="https://vk.com/ekalashnikov81"> <a href="https://vk.com/ekalashnikov81/"> <a href="/saved?lang=ru&amp;fmode=inject&amp;tm=1567237779&amp;tld=ru&amp;la=1566641408&amp;text=Kalashnikov%2CEvgenii&amp;url=https%3A%2F%2Fvk.com%2Fekalashnikov81&amp;l10n=ru&amp;mime=html&amp;sign=287b46925db7ebc34c2171935fd60ead&amp;keyno=0">`; // 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