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

Generated Code

const regex = /(https\:\\\/\\\/video2\.+)([a-zA-Z0-9]+)(\.com\\\/key\=+)([a-zA-Z0-9+-]+)(\,end\=[a-zA-Z0-9]+)(\,limit\=3\\\/data\=)([a-zA-Z0-9]+)(\.[a-zA-Z0-9]+)(\.[a-zA-Z0-9]+)(\.[a-zA-Z0-9]+)(\-mv\\\/speed\=[a-zA-Z0-9]+)(\\\/initial\_buffer\=[a-zA-Z0-9]+)(\\\/[a-zA-Z0-9]+)(\\\/[a-zA-Z0-9]+)(\\\/[a-zA-Z0-9]+)(\\\/[a-zA-Z0-9]+)(\.[a-zA-Z0-9]+)(\.mp4)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(https\\:\\\\\\\/\\\\\\\/video2\\.+)([a-zA-Z0-9]+)(\\.com\\\\\\\/key\\=+)([a-zA-Z0-9+-]+)(\\,end\\=[a-zA-Z0-9]+)(\\,limit\\=3\\\\\\\/data\\=)([a-zA-Z0-9]+)(\\.[a-zA-Z0-9]+)(\\.[a-zA-Z0-9]+)(\\.[a-zA-Z0-9]+)(\\-mv\\\\\\\/speed\\=[a-zA-Z0-9]+)(\\\\\\\/initial\\_buffer\\=[a-zA-Z0-9]+)(\\\\\\\/[a-zA-Z0-9]+)(\\\\\\\/[a-zA-Z0-9]+)(\\\\\\\/[a-zA-Z0-9]+)(\\\\\\\/[a-zA-Z0-9]+)(\\.[a-zA-Z0-9]+)(\\.mp4)', 'gm') const str = `https:\\/\\/thumb-v-cl2.xhcdn.com\\/a\\/UpUWjQ0naov6PDPQutV2gQ\\/009\\/977\\/291\\/320x240.3.jpg","platform":"android","duration":726,"fallback":{"fallbackImageClass":"xplayer-fallback-image"},"hlsConfig":{"libSrc":"https:\\/\\/static-cl.xhcdn.com\\/js\\/hls.js","maxBufferLength":10,"maxBufferSize":10000000,"maxMaxBufferLength":120},"sources":{"standard":{"vp9":[{"url":"https:\\/\\/video5.xhcdn.com\\/key=ArIS24azT212T7rlq2JYOA,end=1534017600,limit=3\\/data=107.12.224.13-mv\\/speed=294k\\/initial_buffer=657952\\/009\\/977\\/291\\/720p.vp9.webm","fallback":"https:\\/\\/19-14.b.cdn13.com\\/009\\/977\\/291\\/720p.vp9.webm?cdn_creation_time=1534003200&cdn_ttl=14400&cdn_bw=294k&cdn_bw_fs=643k&cdn_cv_data=107.12.224.13-mv&cdn_hash=8f32053b3a204e397e1c509d8c55b8c6","quality":"720p","label":"720p","type":"HD"}],"h265":[{"url":"https:\\/\\/video4.xhcdn.com\\/key=USM0qN+ZPKuWvDQ930QxQw,end=1534017600,limit=3\\/data=107.12.224.13-mv\\/speed=232k\\/initial_buffer=657952\\/009\\/977\\/291\\/720p.h265.mp4","fallback":"https:\\/\\/19-13.b.cdn13.com\\/009\\/977\\/291\\/720p.h265.mp4?cdn_creation_time=1534003200&cdn_ttl=14400&cdn_bw=232k&cdn_bw_fs=643k&cdn_cv_data=107.12.224.13-mv&cdn_hash=7d666c372589a913757eecc6c2dc11da","quality":"720p","label":"720p","type":"HD"}],"mp4":[{"url":"https:\\/\\/video2.xhcdn.com\\/key=BiIiv7GdsQSuPxg9SRIrbg,end=1534017600,limit=3\\/data=107.12.224.13-mv\\/speed=464k\\/initial_buffer=657952\\/009\\/977\\/291\\/720p.h264.mp4","fallback":"https:\\/\\/19-11.b.cdn13.com\\/009\\/977\\/291\\/720p.h264.mp4?cdn_creation_time=1534003200&cdn_ttl=14400&cdn_bw=464k&cdn_bw_fs=643k&cdn_cv_data=107.12.224.13-mv&cdn_hash=7e82410ea292a37c1daaf359699d3953","quality":"720p","label":"720p","type":"HD"},{"url":"https:\\/\\/video2.xhcdn.com\\/key=hpb+W+8whtZRJw+jfMdHUw,end=1534017600,limit=3\\/data=107.12.224.13-mv\\/speed=242k\\/initial_buffer=657952\\/009\\/977\\/291\\/480p.h264.mp4","fallback":"https:\\/\\/19-11.b.cdn13.com\\/009\\/977\\/291\\/480p.h264.mp4?cdn_creation_time=1534003200&cdn_ttl=14400&cdn_bw=242k&cdn_bw_fs=643k&cdn_cv_data=107.12.224.13-mv&cdn_hash=49929359209c0d9c6cd7deb8e90ecd22","quality":"480p","label":"480p","type":""},{"url":"https:\\/\\/video2.xhcdn.com\\/key=7geyd-JfggobJpYnpAdaHw,end=1534017600,limit=3\\/data=107.12.224.13-mv\\/speed=120k\\/initial_buffer=657952\\/009\\/977\\/291\\/240p.h264.mp4","fallback":"https:\\/\\/19-11.b.cdn13.com\\/009\\/977\\/291\\/240p.h264.mp4?cdn_creation_time=1534003200&cdn_ttl=14400&cdn_bw=120k&cdn_bw_fs=643k&cdn_cv_data=107.12.224.13-mv&cdn_hash=e251646a2b28b9802a3c6570550001bc","quality":"240p","label":"240p","type":""}]}}`; // 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