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 = /(uddi:)?(.{8}-.{4}-.{4}-.{4}-.{12})/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(uddi:)?(.{8}-.{4}-.{4}-.{4}-.{12})', 'gm') const str = `fc8c266b-c8f2-11e5-9d5f-9e9121fad333 93d3df4b-c8f3-11e5-9d5f-d3f525e3d96f uddi:f0bb22eb-c8f3-11e5-9d5f-ab76fa0fe1ef uddi:a6f8027b-c8f5-11e5-9d5f-be39eae1ed33 uddi:1ee0417b-c8f2-11e5-9d5f-d5eb774576ea uddi:0e87b9f3-de46-11e6-a117-e9c8b22fac1e uddi:eca57383-de46-11e6-a117-9c0349538667 2a759413-de47-11e6-a117-f6cb2452465f Put ProDS NBSWLFRTService NEMEventProcessorService Nationwide_DiscoveryApp PendingTransactionsOrchestrationService UnclearedTransactions-1-0 "MtsiEnquiry service offers methods for the retrieval of information about a customer’s account" "MtsiEnquiry service offers methods for the retrieval of information about a customer’s account" "** Needs Checking as it was missing from CentraSite ** MtsiEnquiry service offers methods for the retrieval of information about a customer’s account" "** Needs Checking as it was missing from CentraSite ** This contains functionality not in 8.3 and needs to be merged back into the next iteration (i.e. any planned 8.4 version) MtsiEnquiry service offers methods for the retrieval of information about a customer’s account" "MtsiEnquiry service offers methods for the retrieval of information about a customer’s account with details like maindetails,additional details,offers ,etc." `; // 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