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

const regex = /^([^,]*,){39}"/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^([^,]*,){39}"', 'gm') const str = `,1414,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,"kepware~5~63CC97F2-5494-43F2-9F92-79A2BEF58D2A","5:39265338",,1473800029,"2016-09-13 20:54:20.206 +0000 Tag=""MODBUS.ROBOT.Position_Base"" Value=""1414"" Quality=""good"" ","RS5c kepware",Kepware,".206","1473800060.206",,,20,13,54,september,20,tuesday,2016,0,,,"24.97.250.66",kepware,1,,,"--_::._+_=""..""_=""""_=""""_",,Kepware,Kepware,RS5c,,,,,,29,0,, ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,"1487.42566",,"kepware~5~63CC97F2-5494-43F2-9F92-79A2BEF58D2A","5:39143140",,1473798904,"2016-09-13 20:35:35.147 +0000 Tag=""OmronCJ.PLC1.Suply_conv.Belt_speed"" Value=""1487.42566"" Quality=""good"" ","RS5c kepware",Kepware,".147","1473798935.147",,,20,13,35,september,35,tuesday,2016,0,,,"24.97.250.66",kepware,1,,,"--_::._+_=""...""_="".""_=""""_",,Kepware,Kepware,RS5c,,,,,,29,0,, ,,,,,,,,,,,,,,,,,,,,,0,,,,,,,,,,,,,,"kepware~5~63CC97F2-5494-43F2-9F92-79A2BEF58D2A","5:39117933",,1473798672,"2016-09-13 20:31:42.457 +0000 Tag=""MODBUS.ROBOT.Velocity_Sholder"" Value=""0"" Quality=""good"" ","RS5cSplunk1 kepware",Kepware,".457","1473798702.457",,,20,13,31,september,42,tuesday,2016,0,,,"24.97.250.66",kepware,1,,,"--_::._+_=""..""_=""""_=""""_",,Kepware,Kepware,RS5c,,,,,,29,0,, ,,,,,,,,,,,,,,,,,,,,,,,,,"1491.82166",,,,,,,,,,"kepware~5~63CC97F2-5494-43F2-9F92-79A2BEF58D2A","5:39105700",,1473798560,"2016-09-13 20:29:50.387 +0000 Tag=""OmronCJ.PLC1.Assy_conv.belt_speed"" Value=""1491.82166"" Quality=""good"" ","RS5c kepware",Kepware,".387","1473798590.387",,,20,13,29,september,50,tuesday,2016,0,,,"24.97.250.66",kepware,1,,,"--_::._+_=""...""_="".""_=""""_",,Kepware,Kepware,RS5c,,,,,,29,0,, ,,,,,,,,,,,,,,,,,,,,1605,,,,,,,,,,,,,,,"kepware~5~63CC97F2-5494-43F2-9F92-79A2BEF58D2A","5:39087971",,1473798396,"2016-09-13 20:27:06.649 +0000 Tag=""MODBUS.ROBOT.Velocity_Max_Wrst3"" Value=""1605"" Quality=""good"" ","RS5c `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions