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]
  • Character class intersection
    [\w&&[^\d]]
  • 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

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(?:[a-z0-9+!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*|""(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21\x23-\x5b\x5d-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])*"")@(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\[(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?|[a-z0-9-]*[a-z0-9]:(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21-\x5a\x53-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])+)\])"; string input = @"[a-zA-Z0-9-_.+]+@[a-zA-Z0-9-_.]+ ekoprasetyo.crb@outlook.com db.maulana@gmail.com. dee.wien@yahoo.com. . ""deninainggolan@yahoo.co.id"" Fajar.rohita@hotmail.com klaas knot (firmansya1404@gmail.aero); dydmm, sss <fransisca+jw@gmail.com>, donny_tri_wardono@yahoo.co.id thank a ""Helpdesk | Energiem**ine"" <helpdesk@ene---ine.nl> invalid: John..Doe@example.com valid: John.Doe@example.com Valid addresses from https://en.wikipedia.org/wiki/Email_address simple@example.com very.common@example.com FirstName.LastName@EasierReading.org x@example.com long.email-address-with-hyphens@and.subdomains.example.com user.name+tag+sorting@example.com name/surname@example.com admin@example example@s.example "" ""@example.org ""john..doe""@example.org mailhost!username@example.org ""very.(),:;<>[]\"".VERY.\""very@\\ \""very\"".unusual""@strange.example.com user%example.com@example.org user-@example.org postmaster@[123.123.123.123] postmaster@[IPv6:2001:0db8:85a3:0000:0000:8a2e:0370:7334] _test@[IPv6:2001:0db8:85a3:0000:0000:8a2e:0370:7334]"; RegexOptions options = RegexOptions.IgnoreCase; foreach (Match m in Regex.Matches(input, pattern, options)) { Console.WriteLine("'{0}' found at index {1}.", m.Value, m.Index); } } }

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 C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx