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 = /"GA_ClientID__c";[^"]*"([^"]*)"/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('"GA_ClientID__c";[^"]*"([^"]*)"', 'gm') const str = `99524";s:9:"FirstName";s:2:"John";s:8:"LastName";s:8:"Doe";s:7:"Company";s:10:"Sample";s:5:"Email";s:20:"xxxxx@gmail.com";s:5:"Phone";s:10:"8888888888";s:7:"Country";s:13:"United States";s:5:"Title";s:8:"Creative";s:5:"State";s:2:"NC";s:13:"Last_Asset__c";s:40:"White Paper: Be a More Strategic Partner";s:16:"Last_Campaign__c";s:18:"70160000000q6TgAAI";s:16:"Referring_URL__c";s:8:"[direct]";s:19:"leadPriorityMarketo";s:2:"P2";s:18:"ProductInterest__c";s:9:"sample";s:14:"landingpageurl";s:359:"https://www.sample.com;mkt_tok=samplesamplesamplesample";s:14:"GA_ClientID__c";s:38:"75714ae471df63202106404675dasd800097erer1849995367";s:13:"Drupal_SID__c";s:36:"e1380c07-0258-47de-aaf8-82d4d8061e1a";s:4:"form";s:4:"1046";} \`\`\` `; // 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