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
Processing...

Test String

Code Generator

Language

Generated Code

const regex = /^(?<Scheme>[file|ftp|https{0,1}|ldap|telnet]+:\/{2})?(?<Subdomain>[a-zA-Z0-9-]{0,4}\.)?(?<Domain>\w+\.\w+\.?\w+\/)(?<Subdirectory>@[\w.]+\/)?(?<Path>[\w_~.-]+\/?[\w_-]+\/{0,1}?[\w_~.-]+)(?<Query>[%?&;].[\w&_~.=-]+)?(?<Fragment>#?[\/\w_-~.,=&-]+)?$/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^(?<Scheme>[file|ftp|https{0,1}|ldap|telnet]+:\\\/{2})?(?<Subdomain>[a-zA-Z0-9-]{0,4}\\.)?(?<Domain>\\w+\\.\\w+\\.?\\w+\\\/)(?<Subdirectory>@[\\w.]+\\\/)?(?<Path>[\\w_~.-]+\\\/?[\\w_-]+\\\/{0,1}?[\\w_~.-]+)(?<Query>[%?&;].[\\w&_~.=-]+)?(?<Fragment>#?[\\\/\\w_-~.,=&-]+)?$', 'gm') const str = `https://medium.com/@s.vive00/7-changes-i-experienced-after-going-1-week-without-added-sugar-9bc48b667f87?source=email-8f87fbd013ca-1581664260785-digest.weekly------0-58------------------2882ae9f_a61e_4d5c_9f87_24f3e0d54cc9-1-----&sectionName=top https://medium.com/@DrAyala/exercise-is-the-answer-heres-why-it-s-a-weight-loss-underperformer-8b64103b8c8f?source=email-8f87fbd013ca-1581664260785-digest.weekly------1-59------------------2882ae9f_a61e_4d5c_9f87_24f3e0d54cc9-1-----&sectionName=top#Fragment-identifier https://www.medium.com/@DrAyala/exercise-is-the-answer-heres-why-it-s-a-weight-loss-underperformer-8b64103b8c8f?source=email-8f87fbd013ca-1581664260785-digest.weekly------1-59------------------2882ae9f_a61e_4d5c_9f87_24f3e0d54cc9-1-----&sectionName=top#Fragment-identifier http://www.yoursite.com/path/to/file.mp3 http://example.com/data.csv#row=4 http://example.com/bar.webm#t=40,80&xywh=160,120,320,240 example.com/data.csv#row=4 example.co.uk/data.csv#row=4`; // 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