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"
"
gm

Test String

Code Generator

Language

Generated Code

re = /^(?![^a-zA-Z0-9])(?:(?![.]{2,})[a-zA-Z0-9_\-.])+(?<![.])@(?:(?![^a-zA-Z0-9])(?:[a-zA-Z0-9_\-])+(?<![^a-zA-Z0-9])\.)+[a-zA-Z]{2,}$/m str = 'email@example.com email@111.222.333.fr firstname.lastname@example.com email@subdomain.example.com 123@gmail.com 123@51gmail62548.com 1234567890@example.com a.defosseux@tbs-education.fr email@example-one.com email@example.name email@example.museum email@example.co.jp firstname-lastname@example.com test@test.com ezf@aezf.fr.en azer123@123.fr a@a.bb a@a.ccc a@bb.bb a.a@bb.bb a.a.a@bb.bb a.a.a@a.bb.bb a.a.a.a@a.a.bb a.a.a.a@a.bb.bb a.a.a.a@a.bb.ccc a.bb.a.a@a.bb.ccc a--a.a@a.bb.ccc a.defosseux@tbs-education.x.fr a.defosseux@tbs-education.x.y.fr a.defosseux@tbs-education.x-e.y.fr email@example-one.com ema.il@example.com e.ma.il@example.com ema-il@example.com e-ma-il@example.com ema--il@example.com em_ail@example.com em__ail@example.com 6email@example.com email6@example.com 6email6@example.com test-test@x.fr tes-t-test@x.fr yasmina.achak@e.rascol.net yasmina.achak@e.rascol.net.aezr.azerz.azer.azreezr.azeraez.azer yasmina.achak@e.rascol.barce yasmina.achak@e.rascol.bar yasmina.achak@e.ba sarah_benabdell@yahoo.fr sarah__benabdellah@yahoo.fr sarah---benabdellah@yahoo.fr sarah___---benabdellah@yahoo.fr marieagnes.paul@off---white.com a.a@bb--bb.ccc a.a@bb--bb.a.ccc a_a@a.bb a_a@a.bb email-@example.com email_@example.com a_@a.bb a._@a.bb a@ccc #@%^%#$@#$@#.com @example.com Joe Smith <email@example.com> email.example.com email@example@example.com email.@example.com email..email@example.com あいうえお@example.com email@example.com (Joe Smith) email@example email@-example.com email@111.222.333.44444 email@example..com a..reds@free.fr Abc..123@example.com ”(),:;<>[\\]@example.com just”not”right@example.com this\\ is"really"not\\allowed@example.com firstname+lastname@example.com email@123.123.123.123 email@[123.123.123.123] "email"@example.com _______@example.com much."more\\ unusual"@example.com very.unusual.”@”.unusual.com@example.com very.”(),:;<>[]”.VERY.”very@\\\\ "very”.unusual@strange.example.com azer aezr@test.com zaetazfe.faezf af@ezfezf ez#!~f@aezf.fr azefé@test.com aze@zaé.com a@a.a a.a@a.a a.a@a.a.a a.a.a.a@a.a.a a.a.a.a@a.a.a.a a..a.a@a.bb.ccc a.é@b.fr azer.@fr .azer@fr a.defosseux@tbs-education-.fr a.defosseux@-tbs-education.fr a.defosseux@-tbs-education-.fr a.defosseux@1234tbs-education.-x-.fr .email@example.com .email.@example.com email.@example.com ema..il@example.com -email@example.com -email-@example.com _email@example.com _email_@example.com _em_ail_@example.com _em__ail_@example.com yaémina.achak@e.rascol.net .-y__as-min-.@eerez.fr yasmina.achak@e.b yasmina.achak@e....bar _a_@a.bb _a@a.bb _.a@a.bb _.a._@a.bb a@_a.bb a@a_.bb a@_a_.bb a@a._bb_.ccc a@a.__a__a__.ccc a@a.__.bb.ccc' # Print the match result str.scan(re) do |match| puts match.to_s end

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html