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

/
/
g

Test String

Code Generator

Language

Generated Code

const regex = /Number\:\s(?<Number>\d+)[\r\n]Category\:\s(?<Category>.*).*[\r\n].*[\r\n].*[\r\n]What\sis\sthe\sspecific\srole\sor\sfunction\sof\sthis\sserver\?\:\s(?<Function>.*).*[\r\n].*[\r\n].*[\r\n].*[\r\n].*[\r\n].*[\r\n].*[\r\n].*[\r\n].*[\r\n].*[\r\n]Server\sHostname\:\s(?<Hostname>.*).*[\r\n]Server\sAllegiance\:\s(?<Domain>.*).*[\r\n].*[\r\n]Physical\sLocation\:\s(?<Location>.*).*[\r\n].*[\r\n].*[\r\n].*[\r\n].*[\r\n]Local\sAdministrators\:\s+([\w\s]+)[\r\n].*[\r\n].*[\r\n]Task\sDescription\:\s(?<Task>.*)/g; // Alternative syntax using RegExp constructor // const regex = new RegExp('Number\\:\\s(?<Number>\\d+)[\\r\\n]Category\\:\\s(?<Category>.*).*[\\r\\n].*[\\r\\n].*[\\r\\n]What\\sis\\sthe\\sspecific\\srole\\sor\\sfunction\\sof\\sthis\\sserver\\?\\:\\s(?<Function>.*).*[\\r\\n].*[\\r\\n].*[\\r\\n].*[\\r\\n].*[\\r\\n].*[\\r\\n].*[\\r\\n].*[\\r\\n].*[\\r\\n].*[\\r\\n]Server\\sHostname\\:\\s(?<Hostname>.*).*[\\r\\n]Server\\sAllegiance\\:\\s(?<Domain>.*).*[\\r\\n].*[\\r\\n]Physical\\sLocation\\:\\s(?<Location>.*).*[\\r\\n].*[\\r\\n].*[\\r\\n].*[\\r\\n].*[\\r\\n]Local\\sAdministrators\\:\\s+([\\w\\s]+)[\\r\\n].*[\\r\\n].*[\\r\\n]Task\\sDescription\\:\\s(?<Task>.*)', 'g') const str = `Task # 12347859 has been opened and assigned to XXXXXXX - . Task # 12347859 Client Details Jackie Newman servicedesk@thenet.com Assignment Details User course@email.com Status and Priority Details Urgency: 4-LOW Impact: 4-MINOR Status: Assigned Task Details Number: 12347859 Category: Add/Upgrade Server Software Application: Production Web Server Linked Record: CR123458756 - 2-Implementation What is the specific role or function of this server?: XXXXXXXXXXXX What is the primary application for this server deployment?: XXXXXXXXXXXXX Provide a detailed description that explains the function or role of the server.: XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX It will also be used as a proxy Card Recon scan server to scan application databases Is this replacing an existing server?: Si Please explain when will the old server be decommissioned?: XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Is this a physical or virtual server?: XXXXXXXXX What is the required Operating System?: XXXXXXXXX Patching Schedule: XXXXXXXXX Environment - Is the server Production, Development or Disaster Recovery?: XXXXXXXXX Server Hostname: XXXXXXXXX Server Allegiance: XXXXXXXXX Will SQL Server be required on this server?: XXX Physical Location: XXXXXXXXX Include in Enterprise Backups?: XX Resource Requirements: RAM: XXXX Resource Requirements: CPUs: XX Resource Requirements: Disk [Quantity and Size(s)]: 40GB Local Administrators: XXXXXXXXX XXXXXXXXX XXXXXXXXX XXXXXXXXX Directories to be excluded from Anti-Virus scanning: None Additional Comments: Task Description: XXXXXXXXX `; // 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