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 = /^((?!V2).)*- Master\s*$/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^((?!V2).)*- Master\\s*$', 'gm') const str = `AppMessages V2 - Dev AppMessages V2 - Master AWS - Octopus Release Bellhop Model V2 - Dev Bellhop Model V2 - Master BellHop Services V2 - Dev BellHop Services V2 - Master BellHop V2 - Dev BellHop V2 - Master BSG Log4j Extras V2 - Dev BSG Log4j Extras V2 - Master BSG-BOM - Dev BSG-BOM - Master BSG-BOM V2 - Dev BSG-BOM V2 - Master Core Model V2 - Dev Core Model V2 - Master Core Services V2 - Dev Core Services V2 - Master DealerLocator - Dev EMS Services V2 - Dev EMS Services V2 - Master Entitlements REST API V2 - Dev Entitlements REST API V2 - Master Entitlements Services V2 - Dev Entitlements Services V2 - Master Entitlements SOAP API V2 - Dev Entitlements SOAP API V2 - Master FlexNet Services - Dev FlexNet Services - Master GetNodeInfo BusSys-Build-Slave-01 GetNodeInfo BusSys_Corp_Build_Slave GetNodeInfo Master Laipac Services V2 - Dev Laipac Services V2 - Master LDK Services V2 - Dev LDK Services V2 - Master LicenseAdmin - Dev LicenseAdmin - Master List All Jobs Lite Services V2 - Dev Lite Services V2 - Master LiteFlexNetIntegration V2 - Dev LiteFlexNetIntegration V2 - Master LiteIntegration - Dev LiteIntegration - Master Messaging Services V2 - Dev Messaging Services V2 - Master MTPConsumer - Dev MTPConsumer - Master OptionKeys - Dev OptionKeys - Master OptionKeysAPI - Dev OptionKeysAPI - Master Panther REST API V2 - Dev Pools API V2 - Dev Pools API V2 - Master Pools Model V2 - Dev Pools Model V2 - Master Pools Services V2 - Dev Pools Services V2 - Master Preconfigured API V2 - Dev Preconfigured API V2 - Master SCL Client V2 - Dev SCL Client V2 - Master SentinelCloud Services V2 - Dev SentinelCloud Services V2 - Master SubscriptionManager V2 - Dev SubscriptionManager V2 - Master TermsOfService - Master Test Support V2 - Dev Test Support V2 - Master Tid Services V2 - Dev Tid Services V2 - Master Upload templates to S3 - branch2Dev Upload templates to S3 - Dev Upload templates to S3 - Master Upload templates to S3 - Test VirtualWarehouse - Dev VirtualWarehouse - Master VirtualWarehouse Services V2 - Dev VirtualWarehouse Services V2 - Master VW Lite API - Dev VW Lite API - Master VW Remedy Events - Dev VW Remedy Events - Master VW Remedy Events Consumer - Dev VW Remedy Events Consumer - Master VW Remedy Events Lib - Dev VW Remedy Events Lib - Master VW Scheduled Tasks V2 - Dev VW Scheduled Tasks V2 - Master VW Sentinel V2 - Dev VW Sentinel V2 - Master VW Subscriptions V2 - Dev VW Subscriptions V2 - Master VW5 - Dev VW5 - Master WooCommerce API V2 - Dev WooCommerce API V2 - Master WooCommerce Model V2 - Dev WooCommerce Model V2 - Master WooCommerce Services V2 - Dev WooCommerce Services V2 - Master`; // 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