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 = /^((http|https):\/\/)?(www.)?(?!.*(http|https|www.))[a-zA-Z0-9_-]+(\.[a-zA-Z]+)+(\/)?.([\w\?[a-zA-Z-_%\/@?]+)*([^\/\w\?[a-zA-Z0-9_-]+=\w+(&[a-zA-Z0-9_]+=\w+)*)?$/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^((http|https):\\\/\\\/)?(www.)?(?!.*(http|https|www.))[a-zA-Z0-9_-]+(\\.[a-zA-Z]+)+(\\\/)?.([\\w\\?[a-zA-Z-_%\\\/@?]+)*([^\\\/\\w\\?[a-zA-Z0-9_-]+=\\w+(&[a-zA-Z0-9_]+=\\w+)*)?$', 'gm') const str = `httpsa://localhost/pwa/deals https://localhost/pwa/deals https://localhost/pwa/deals https://localhost/pwa/deals/api/sdsdsd fb.com/animesh sleeptight.com multitasking.com a2.com asdasdasd.com sdsdc check abunes.com/ #.in google@http://asd.com animes@google.com test@test.com --2- www.com http://www.computer.com.au/ f4.animesh@google.com https://animeshsingh.in http://animeshsingh.in/ someone.ag someone.br/ads www.test-my-skills.gov.cz/0999asd-xzc88?0-_/sad%20123/@asdas Http://www.@test.com Https://www.@test.com https://asa .aasd.com test@asda.test.cas someone.com asdasd.com/asdasd/asdasd/asdasd/@asasd ftp://siva:asdas@sadasd/asd adc 2@https://www.go.com www.google.com https://www.somehow.com/@aasd https://www.test.facebook.com/@sdas Https://www.test.com/@masdasd www.instagram.com/f4animesh http://www.animeshsingh.in www.ASD.com`; // 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