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

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"^\$?[0-9]{1,3}(?:,[0-9]{3})*(?:\.[0-9]+)?$"; string input = @"Here are some test cases that it needs to match 76,249.25 131,588.00 7.09 21.27 420.42 54.77 32.848 3,056.12 0.009 0.01 32.85 2,948.59 $99,249.25 $9.0000 $1,800.0000 $1,000,000 Here are some test cases that it should not target 666-257-6443 F1A 5G9 Bolt, Locating, M8 x 1.25 x 30 L Precision Washer, 304 SS, 0.63 OD x 0.31 Flat Washer 300 Series SS; Pack of 50 U-SSFAN 0.63-L6.00-F0.75-B0.64-T0.38-SC5.62 U-CLBUM 0.63-D0.88-L0.875 U-WSSS 0.38-D0.88-T0.125 U-BGHK 6002ZZ - H1.50 U-SSCS 0.38-B0.38 6412K42 Std Dowel, 3/8"" x 1-1/2"" Lg, Steel 2019.07.05 2092-002.0180 SHCMG 0.25-L1.00 280160717"; 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