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

r"
"
gis

Test String

Code Generator

Language

Generated Code

const regex = new RegExp('(?#remove next set of parenthesis and content because its only for simulating automod)(^|\\W|\\b)(?<!player\\.)(?<!blog\\.)(?<!dev\\.)(?<!link\\.)(?<!affiliate\\.)(?<!meetups\\.)(?<!help\\.)(?<!safety\\.)(?<!devstatus\\.)(?<!brand\\.)(?<!sings\\.)(?<!music\\.)twitch\\.tv\\/(?!embed(\\/|\\b)|subs(\\/|\\b)|directory(\\/|\\b)|p\\/|user(\\/|\\b)|legal(\\/|\\b)|admin(\\/|\\b)|login(\\/|\\b)|signup(\\/|\\b)|jobs(\\/|\\b)|videos(\\/|\\b)|collections(\\/|\\b)|downloads(\\/|\\b)|turbo(\\/|\\b)|store(\\/|\\b)|creatorcamp(\\/|\\b)|settings(\\/|\\b)|giftcard(\\/|\\b)|redeem(\\/|\\b)|broadcast(\\/|\\b)|partner(\\/|\\b)|bits(\\/|\\b)|prime(\\/|\\b))(\\w+)\\/?(?!\\S)(?#remove next set of parenthesis and content because its only for simulating automod)($|\\W|\\b)', 'gis') const str = `https://www.twitch.tv/miametzmusic https://www.twitch.tv/miametzmusic https://twitch.tv/summit1g https://twitch.tv/summit1g/ https://www.twitch.tv/subsp00ky https://www.twitch.tv/subsp00ky/ https://player.twitch.tv/js/embed/v1.js https://player.twitch.tv/?channel=miametzmusic&parent=www.example.com https://www.twitch.tv/embed/miametzmusic/chat?parent=www.example.com https://www.twitch.tv/subs https://www.twitch.tv/subs/miametzmusic https://www.twitch.tv/directory https://www.twitch.tv/directory/all/tags/classical https://www.twitch.tv/miametzmusic/about https://www.twitch.tv/miametzmusic/schedule https://www.twitch.tv/miametzmusic/videos https://www.twitch.tv/videos/1821013434 https://www.twitch.tv/videos/1821013434?t=00h00m13s https://www.twitch.tv/collections/EwAtC1IWzhY3Ww https://www.twitch.tv/videos/1277407565?collection=EwAtC1IWzhY3Ww https://www.twitch.tv/videos/1277407565?collection=EwAtC1IWzhY3Ww&t=00h00m52s https://player.twitch.tv/?collection=EwAtC1IWzhY3Ww&video=1277407565&parent=www.example.com https://player.twitch.tv/?collection=EwAtC1IWzhY3Ww&video=1277407565&time=0h2m27s&parent=www.example.com https://www.twitch.tv/p/giftcard/ https://www.twitch.tv/p/about https://www.twitch.tv/p/en/about/ https://blog.twitch.tv/ https://blog.twitch.tv/en/ https://blog.twitch.tv/en/archive/2023/ https://dev.twitch.tv/ https://dev.twitch.tv/products/ https://www.twitch.tv/downloads https://www.twitch.tv/jobs https://www.twitch.tv/jobs/en/ https://www.twitch.tv/turbo https://www.twitch.tv/store https://www.twitch.tv/creatorcamp https://www.twitch.tv/creatorcamp/en/paths/ https://www.twitch.tv/settings/security https://link.twitch.tv/devchat https://affiliate.twitch.tv/ https://meetups.twitch.tv/ https://meetups.twitch.tv/events https://help.twitch.tv/ https://help.twitch.tv/s/article/getting-started-twitch-studio https://www.twitch.tv/giftcard/buy?ref_=gc_twitch_landing https://www.twitch.tv/redeem https://safety.twitch.tv/ https://safety.twitch.tv/s/article/Usernames https://devstatus.twitch.tv/ https://devstatus.twitch.tv/uptime https://www.twitch.tv/broadcast/studio https://brand.twitch.tv/ https://brand.twitch.tv/downloads/twitch-brand-assets.zip https://www.twitch.tv/partner/signup https://www.twitch.tv/bits https://www.twitch.tv/prime https://sings.twitch.tv/ https://music.twitch.tv/`; // 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