Regular Expressions 101

Save & Share

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
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

/
/
gmi

Test String

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"^https?:\/\/[^\/]+(\/d\/|\/m\/)"; string input = @"https://internet.hughesnet.com/d/order/?exp=1 https://test-internet.hughesnet.redventures.com/d/order/?exp=1 http://localhost-internet.hughesnet.redventures.com/d/order/?exp=1 https://internet.hughesnet.com/mobile/order/?exp=1 https://test-internet.hughesnet.redventures.com/mobile/order/?exp=1 http://localhost-internet.hughesnet.redventures.com/mobile/order/?exp=1 https://internet.hughesnet.com/m/order/?exp=1 https://test-internet.hughesnet.redventures.com/m/order/?exp=1 http://localhost-internet.hughesnet.redventures.com/m/order/?exp=1 https://internet.hughesnet.com/order/?exp=1 https://test-internet.hughesnet.redventures.com/order/?exp=1 http://localhost-internet.hughesnet.redventures.com/order/?exp=1 https://internet.hughesnet.com/?exp=1 https://test-internet.hughesnet.redventures.com/?exp=1 http://localhost-internet.hughesnet.redventures.com/?exp=1 https://www.directvdeals.com/d/bundles.html https://www.directvdeals.com/d/?hnkw=%2Bhughesnet&s_ace=&s_adp=1t1&s_agid=39321230140&s_aid=221800323027&s_cid=739574798&s_dvc=c&s_kid=22337170519&s_loci=&s_locp=9010670&s_ntwk=g&s_pid=1&s_plid=&s_sid=197&s_tgtid=aud-329726877564:kwd-22337170519&utm_mcid=3198048&utm_source=google&utm_medium=cpc&utm_term=%2Bhughesnet&utm_cmpid=739574798&utm_adgid=39321230140&utm_tgtid=aud-329726877564:kwd-22337170519&utm_mt=b&utm_adid=221800323027&utm_dvc=c&utm_ntwk=g&utm_adpos=1t1&utm_plcmnt=&utm_locphysid=9010670&utm_locintid=&utm_feeditemid=&utm_devicemdl=&utm_plcmnttgt=&gclid=CjwKCAjw36DpBRAYEiwAmVVDMMUJoi-t1iWDby7eC5zV3HqMA4RM9iIDsihOnFwTNw9P2seGKtSfoRoCuTMQAvD_BwE"; RegexOptions options = RegexOptions.Multiline | 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