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 = /((?:\/|v=|vi=|v%)(?<id>([\-\w]){10,14}))/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('((?:\\\/|v=|vi=|v%)(?<id>([\\-\\w]){10,14}))', 'gm') const str = `youtu.be/DFYRQ_zQ-gk DFYRQ_zQ-gk https://youtu.be/KjpQF3nYGoc?list=PLakykuPxo3cgydAififYWycQdFKpXZLYr&t=1 http://www.youtube.com/watch?v=-wtIMTCHWuI http://youtube.com/watch?v=-wtIMTCHWuI http://m.youtube.com/watch?v=-wtIMTCHWuI http://www.youtube.com/watch/-wtIMTCHWuI http://youtube.com/watch/-wtIMTCHWuI http://m.youtube.com/watch/-wtIMTCHWuI http://www.youtube.com/v/dQw4w9WgXcQ http://youtube.com/v/dQw4w9WgXcQ http://m.youtube.com/v/dQw4w9WgXcQ http://www.youtube.com/watch?v=yZv2daTWRZU&feature=em-uploademail http://youtube.com/watch?v=yZv2daTWRZU&feature=em-uploademail http://m.youtube.com/watch?v=yZv2daTWRZU&feature=em-uploademail http://www.youtube.com/watch?v=0zM3nApSvMg&feature=feedrec_grec_index http://youtube.com/watch?v=0zM3nApSvMg&feature=feedrec_grec_index http://m.youtube.com/watch?v=0zM3nApSvMg&feature=feedrec_grec_index http://www.youtube.com/watch?v=0zM3nApSvMg#t=0m10s http://youtube.com/watch?v=0zM3nApSvMg#t=0m10s http://m.youtube.com/watch?v=0zM3nApSvMg#t=0m10s http://www.youtube.com/watch?v=cKZDdG9FTKY&feature=channel http://youtube.com/watch?v=cKZDdG9FTKY&feature=channel http://m.youtube.com/watch?v=cKZDdG9FTKY&feature=channel http://www.youtube.com/watch?v=lalOy8Mbfdc&playnext_from=TL&videos=osPknwzXEas&feature=sub http://youtube.com/watch?v=lalOy8Mbfdc&playnext_from=TL&videos=osPknwzXEas&feature=sub http://m.youtube.com/watch?v=lalOy8Mbfdc&playnext_from=TL&videos=osPknwzXEas&feature=sub http://www.youtube.com/watch?v=lalOy8Mbfdc&feature=youtu.be http://youtube.com/watch?v=lalOy8Mbfdc&feature=youtu.be http://m.youtube.com/watch?v=lalOy8Mbfdc&feature=youtu.be http://www.youtube.com/watch?v=dQw4w9WgXcQ&feature=youtube_gdata_player http://youtube.com/watch?v=dQw4w9WgXcQ&feature=youtube_gdata_player http://m.youtube.com/watch?v=dQw4w9WgXcQ&feature=youtube_gdata_player http://www.youtube.com/watch?v=ishbTyLs6ps&list=PLGup6kBfcU7Le5laEaCLgTKtlDcxMqGxZ&index=106&shuffle=2655 http://youtube.com/watch?v=ishbTyLs6ps&list=PLGup6kBfcU7Le5laEaCLgTKtlDcxMqGxZ&index=106&shuffle=2655 http://m.youtube.com/watch?v=ishbTyLs6ps&list=PLGup6kBfcU7Le5laEaCLgTKtlDcxMqGxZ&index=106&shuffle=2655 http://www.youtube.com/watch?feature=player_embedded&v=dQw4w9WgXcQ http://youtube.com/watch?feature=player_embedded&v=dQw4w9WgXcQ http://m.youtube.com/watch?feature=player_embedded&v=dQw4w9WgXcQ http://www.youtube.com/watch?app=desktop&v=dQw4w9WgXcQ http://youtube.com/watch?app=desktop&v=dQw4w9WgXcQ http://m.youtube.com/watch?app=desktop&v=dQw4w9WgXcQ http://www.youtube.com/watch/-wtIMTCHWuI?app=desktop http://youtube.com/watch/-wtIMTCHWuI?app=desktop http://m.youtube.com/watch/-wtIMTCHWuI?app=desktop http://www.youtube.com/v/-wtIMTCHWuI?version=3&autohide=1 http://youtube.com/v/-wtIMTCHWuI?version=3&autohide=1 http://m.youtube.com/v/-wtIMTCHWuI?version=3&autohide=1 http://www.youtube.com/v/0zM3nApSvMg?fs=1&hl=en_US&rel=0 http://youtube.com/v/0zM3nApSvMg?fs=1&hl=en_US&rel=0 http://m.youtube.com/v/0zM3nApSvMg?fs=1&hl=en_US&rel=0 https://www.youtube.com/v/0zM3nApSvMg?fs=1&amp;hl=en_US&amp;rel=0 http://www.youtube.com/v/dQw4w9WgXcQ?feature=youtube_gdata_player http://youtube.com/v/dQw4w9WgXcQ?feature=youtube_gdata_player http://m.youtube.com/v/dQw4w9WgXcQ?feature=youtube_gdata_player http://youtu.be/-wtIMTCHWuI https://youtu.be/-wtIMTCHWuI https://youtu.be/dQw4w9WgXcQ?feature=youtube_gdata_player https://youtu.be/oTJRivZTMLs?list=PLToa5JuFMsXTNkrLJbRlB--76IAOjRM9b https://youtu.be/oTJRivZTMLs&feature=channel http://youtu.be/lalOy8Mbfdc?t=1 http://youtu.be/lalOy8Mbfdc?t=1s http://youtu.be/M9bq_alk-sw?si=B_RZg_I-lLaa7UU- http://www.youtube.com/oembed?url=http%3A//www.youtube.com/watch?v%3D-wtIMTCHWuI&format=json http://youtube.com/oembed?url=http%3A//www.youtube.com/watch?v%3D-wtIMTCHWuI&format=json http://m.youtube.com/oembed?url=http%3A//www.youtube.com/watch?v%3D-wtIMTCHWuI&format=json http://www.youtube.com/attribution_link?a=JdfC0C9V6ZI&u=%2Fwatch%3Fv%3DEhxJLojIE_o%26feature%3Dshare http://youtube.com/attribution_link?a=JdfC0C9V6ZI&u=%2Fwatch%3Fv%3DEhxJLojIE_o%26feature%3Dshare http://m.youtube.com/attribution_link?a=JdfC0C9V6ZI&u=%2Fwatch%3Fv%3DEhxJLojIE_o%26feature%3Dshare http://www.youtube.com/attribution_link?a=8g8kPrPIi-ecwIsS&u=/watch%3Fv%3DyZv2daTWRZU%26feature%3Dem-uploademail http://youtube.com/attribution_link?a=8g8kPrPIi-ecwIsS&u=/watch%3Fv%3DyZv2daTWRZU%26feature%3Dem-uploademail http://m.youtube.com/attribution_link?a=8g8kPrPIi-ecwIsS&u=/watch%3Fv%3DyZv2daTWRZU%26feature%3Dem-uploademail http://www.youtube.com/embed/lalOy8Mbfdc http://youtube.com/embed/lalOy8Mbfdc http://m.youtube.com/embed/lalOy8Mbfdc http://www.youtube.com/embed/nas1rJpm7wY?rel=0 http://youtube.com/embed/nas1rJpm7wY?rel=0 http://m.youtube.com/embed/nas1rJpm7wY?rel=0 http://www.youtube-nocookie.com/embed/lalOy8Mbfdc?rel=0 https://www.youtube-nocookie.com/embed/lalOy8Mbfdc?rel=0 http://www.youtube.com/e/dQw4w9WgXcQ http://youtube.com/e/dQw4w9WgXcQ http://m.youtube.com/e/dQw4w9WgXcQ http://www.youtube.com/shorts/j9rZxAF3C0I http://youtube.com/shorts/j9rZxAF3C0I http://m.youtube.com/shorts/j9rZxAF3C0I http://www.youtube.com/shorts/j9rZxAF3C0I?app=desktop http://youtube.com/shorts/j9rZxAF3C0I?app=desktop http://m.youtube.com/shorts/j9rZxAF3C0I?app=desktop http://www.youtube.com/live/8hBmepWUJoc http://youtube.com/live/8hBmepWUJoc http://m.youtube.com/live/8hBmepWUJoc http://www.youtube.com/live/8hBmepWUJoc?app=desktop http://youtube.com/live/8hBmepWUJoc?app=desktop http://m.youtube.com/live/8hBmepWUJoc?app=desktop https://youtube.com/user/GitHub#p/a/u/1/lalOy8Mbfdc https://www.youtube.com/user/GitHub#p/u/1/lalOy8Mbfdc https://www.youtube.com/user/GitHub#p/u/1/lalOy8Mbfdc?rel=0 https://www.youtube.com/user/GitHub#p/a/u/2/lalOy8Mbfdc https://www.youtube.com/user/GitHub#p/u/11/lalOy8Mbfdc https://www.youtube.com/user/GitHub#p/u/1/lalOy8Mbfdc https://www.youtube.com/GitHub?v=lalOy8Mbfdc http://www.youtube.com/?v=dQw4w9WgXcQ http://youtube.com/?v=dQw4w9WgXcQ&feature=youtube_gdata_player http://youtube.com/?v=lalOy8Mbfdc&feature=channel http://youtube.com/?vi=dQw4w9WgXcQ http://youtube.com/?vi=dQw4w9WgXcQ&feature=youtube_gdata_player http://youtube.com/?vi=lalOy8Mbfdc&feature=channel http://www.youtube.com/?feature=player_embedded&v=dQw4w9WgXcQ http://youtube.com/?feature=channel&v=lalOy8Mbfdc http://youtube.com/watch?vi=dQw4w9WgXcQ http://youtube.com/watch?vi=dQw4w9WgXcQ&feature=youtube_gdata_player http://youtube.com/watch?vi=lalOy8Mbfdc&feature=channel http://youtube.com/vi/dQw4w9WgXcQ http://youtube.com/vi/dQw4w9WgXcQ?feature=youtube_gdata_player http://youtube.com/vi/lalOy8Mbfdc&feature=channel dead domain: http://www.youtube-nocookie.com/v/6L3ZvIMwZFM?version=3&hl=en_US&rel=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