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
No Match

/
/
gm

Test String

Code Generator

Language

Generated Code

const regex = /(([\w\.]+)(\.[^/\n]+)\/?(.*\/?)*) /gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(([\\w\\.]+)(\\.[^\/\\n]+)\\\/?(.*\\\/?)*) ', 'gm') const str = `google.map.com google.com youtube.com/die_bro y0ut_ube.com tmall.com tmall.com/yo/got/mail facebook.com facebook.com baidu.com baidu.com qq.com qq.com sohu.com sohu.com login.tmall.com login.tmall.com taobao.com taobao.com yahoo.com yahoo.com JD.com JD.com JD.com JD.com jd.com jd.com amazon.com amazon.com sina.com sina.com weibo.com weibo.com pages.tmall.com pages.tmall.com live.com live.com reddit.com reddit.com netflix.com netflix.com xinhuanet.com xinhuanet.com Okezone.com Okezone.com Okezone.com Okezone.com okezone.com okezone.com blogspot.com blogspot.com office.com office.com microsoft.com microsoft.com vk.com vk.com csdn.net csdn.net instagram.com instagram.com alipay.com alipay.com bing.com bing.com google.com google.com bongacams.com bongacams.com microsoftonline.com microsoftonline.com livejasmin.com livejasmin.com tribunnews.com tribunnews.com twitter.com twitter.com stackoverflow.com stackoverflow.com naver.com naver.com Amazon.com Amazon.com Amazon.com Amazon.com aliexpress.com aliexpress.com ebay.com ebay.com`; // 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