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('(?!letsgo\\.|shop\\.|advertise\\.|static\\.|www\\.)((\\w|-)+\\.)(tumblr\\.com|tmblr\\.co)\\/?(?!\\S)', 'gis') const str = `Match the following: https://dhabitahpunk-art.tumblr.com/ https://cdn.tumblr.com DON'T match the following: https://www.tumblr.com/todayontumblr tumblr.com/todayontumblr https://www.tumblr.com/todayontumblr/ tumblr.com/todayontumblr/ https://www.tumblr.com/dhabitahpunk-art tumblr.com/dhabitahpunk-art https://www.tumblr.com/dhabitahpunk-art/ tumblr.com/dhabitahpunk-art/ https://tmblr.co/MzB5rhaOrTp3uwB5NhcQsEw https://www.tumblr.com/blog/view/grouper/ https://www.tumblr.com/internships https://www.tumblr.com/transparency https://www.tumblr.com/search/lana https://www.tumblr.com/tagged/lwaxana%20troi?sort=top https://www.tumblr.com/following https://tumblr.com/customize/ https://letsgo.tumblr.com/ https://letsgo.tumblr.com/welcome-guide https://64.media.tumblr.com/6c05087e5dbaccedf651d421148dfaa0/e7eb8d73a9a6cc70-8e/s540x810/e9cc402adacca3e983fc0448b94919b9f809c719.gifv https://shop.tumblr.com/ https://shop.tumblr.com/new/ https://www.tumblr.com/tumblrmart/blue-checkmark https://help.tumblr.com/hc/articles/115001572547 https://help.tumblr.com/hc https://tumblr.com/help https://api.tumblr.com/console https://www.tumblr.com/oauth/apps https://www.tumblr.com/api https://assets.tumblr.com/downloads https://www.tumblr.com/abuse https://www.tumblr.com/themes/ https://www.tumblr.com/themes/tagged/two_column https://www.tumblr.com/dmca https://www.tumblr.com/docs/api_agreement https://www.tumblr.com/account/delete https://www.tumblr.com/settings https://www.tumblr.com/settings/blog https://www.tumblr.com/security https://www.tumblr.com/developers https://www.tumblr.com/press https://www.tumblr.com/buttons https://www.tumblr.com/logo https://www.tumblr.com/tips https://www.tumblr.com/support https://www.tumblr.com/auth https://www.tumblr.com/auth/google?redirectTo=undefined https://www.tumblr.com/register https://www.tumblr.com/register?source=new_to_tumblr https://www.tumblr.com/login https://www.tumblr.com/login?redirect_to=%2Fexplore%2Ftoday https://www.tumblr.com/explore https://www.tumblr.com/explore/trending https://advertise.tumblr.com/ https://advertise.tumblr.com/#why https://www.tumblr.com/jobs https://www.tumblr.com/policy https://www.tumblr.com/privacy_policy https://www.tumblr.com/policy/privacy https://www.tumblr.com/policy/terms-of-service https://www.tumblr.com/apps https://www.tumblr.com/about https://about.tumblr.com/#quick-facts https://www.tumblr.com/ https://www.tumblr.com/dhabitahpunk-art/tagged/Picturesque tumblr.com/dhabitahpunk-art/tagged/Picturesque tumblr.com https://dhabitahpunk-art.tumblr.com/page/2 dhabitahpunk-art.tumblr.com/page https://dhabitahpunk-art.tumblr.com/page/ https://dhabitahpunk-art.tumblr.com/commissions https://dhabitahpunk-art.tumblr.com/post/714262490632044544/time-taken-355-hoursreference-unknown https://static.tumblr.com/ https://static.tumblr.com/zyubucd/CIjopeea7/transparencyreport2016b.pdf`; // 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