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

/
/
mg

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"^([\d.]+) (\S+) (\S+) \[([\w:\/]+\s[+\-]\d{4})\] ""GET (.+?) HTTP\/1\.1"" (\d{3}) (\d+) ""([^""]+)"" ""([^""]+)"""; string input = @"79.133.215.123 - - [14/Jun/2014:10:30:13 -0400] ""GET /home HTTP/1.1"" 200 1671 ""-"" ""Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.1916.153 Safari/537.36"" 162.235.161.200 - - [14/Jun/2014:10:30:13 -0400] ""GET /department/apparel/category/featured%20shops/product/adidas%20Kids'%20RG%20III%20Mid%20Football%20Cleat HTTP/1.1"" 200 1175 ""-"" ""Mozilla/5.0 (Macintosh; Intel Mac OS X 10_9_3) AppleWebKit/537.76.4 (KHTML, like Gecko) Version/7.0.4 Safari/537.76.4"" 39.244.91.133 - - [14/Jun/2014:10:30:14 -0400] ""GET /department/fitness HTTP/1.1"" 200 1435 ""-"" ""Mozilla/5.0 (Macintosh; Intel Mac OS X 10_9_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.1916.153 Safari/537.36"" 150.47.54.136 - - [14/Jun/2014:10:30:14 -0400] ""GET /department/fan%20shop/category/water%20sports/product/Pelican%20Sunstream%20100%20Kayak/add_to_cart HTTP/1.1"" 200 1932 ""-"" ""Mozilla/5.0 (Macintosh; Intel Mac OS X 10_9_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.1916.153 Safari/537.36"" 217.89.36.129 - - [14/Jun/2014:10:30:14 -0400] ""GET /view_cart HTTP/1.1"" 200 1401 ""-"" ""Mozilla/5.0 (Windows NT 6.1; WOW64; rv:30.0) Gecko/20100101 Firefox/30.0"" 36.44.59.115 - - [14/Jun/2014:10:30:15 -0400] ""GET /department/footwear/category/cardio%20equipment HTTP/1.1"" 200 386 ""-"" ""Mozilla/5.0 (Windows NT 6.1; WOW64; rv:30.0) Gecko/20100101 Firefox/30.0"" 11.252.83.179 - - [14/Jun/2014:10:30:15 -0400] ""GET /view_cart HTTP/1.1"" 200 1726 ""-"" ""Mozilla/5.0 (Macintosh; Intel Mac OS X 10_9_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.1916.153 Safari/537.36"" 56.251.19.230 - - [14/Jun/2014:10:30:15 -0400] ""GET /department/footwear/category/fitness%20accessories HTTP/1.1"" 200 2076 ""-"" ""Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.1916.153 Safari/537.36"" 137.95.229.186 - - [14/Jun/2014:10:30:16 -0400] ""GET /department/fan%20shop/category/fishing/product/Field%20&%20Stream%20Sportsman%2016%20Gun%20Fire%20Safe HTTP/1.1"" 200 1413 ""-"" ""Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.1916.153 Safari/537.36"" 100.98.159.99 - - [14/Jun/2014:10:30:16 -0400] ""GET /department/fan%20shop/category/water%20sports/product/Pelican%20Sunstream%20100%20Kayak HTTP/1.1"" 200 396 ""-"" ""Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.1916.153 Safari/537.36"" 137.95.229.186 - - [14/Jun/2014:10:30:16 -0400] ""GET /home HTTP/1.1"" 200 1473 ""-"" ""Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.1916.153 Safari/537.36"" 86.214.1.70 - - [14/Jun/2014:10:30:17 -0400] ""GET /department/fan%20shop HTTP/1.1"" 200 771 ""-"" ""Mozilla/5.0 (Macintosh; Intel Mac OS X 10_9_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/36.0.1985.125 Safari/537.36"" 18.168.113.227 - - [14/Jun/2014:10:30:17 -0400] ""GET /support HTTP/1.1"" 200 1321 ""-"" ""Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.1916.153 Safari/537.36"" 133.20.136.170 - - [14/Jun/2014:10:30:18 -0400] ""GET /home HTTP/1.1"" 200 1238 ""-"" ""Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.1916.153 Safari/537.36"" 137.95.229.186 - - [14/Jun/2014:10:30:18 -0400] ""GET /home HTTP/1.1"" 200 1797 ""-"" ""Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.1916.153 Safari/537.36"" 100.158.186.50 - - [14/Jun/2014:10:30:18 -0400] ""GET /home HTTP/1.1"" 200 878 ""-"" ""Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.1916.153 Safari/537.36"" 36.44.59.115 - - [14/Jun/2014:10:30:19 -0400] ""GET /checkout HTTP/1.1"" 200 1551 ""-"" ""Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko"" "; RegexOptions options = RegexOptions.Multiline; 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