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 = /^.*?CEF:\d+\|(?<severity>.*?)\|(?<group>.*?)\|(?<process>\d+)\|-SiteId\s\((?<processid>\d+)\)\s(?<url>.*?)\s.[^\s]+\s(?<recipient>.*?)\|-RuleName\s(?<threatname>[^\|]+)\|-ActionTakenRequest(?<action>[^\|]+)\|EntryPage\s(?<subject>.*?)\s/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^.*?CEF:\\d+\\|(?<severity>.*?)\\|(?<group>.*?)\\|(?<process>\\d+)\\|-SiteId\\s\\((?<processid>\\d+)\\)\\s(?<url>.*?)\\s.[^\\s]+\\s(?<recipient>.*?)\\|-RuleName\\s(?<threatname>[^\\|]+)\\|-ActionTakenRequest(?<action>[^\\|]+)\\|EntryPage\\s(?<subject>.*?)\\s', 'gm') const str = `may. 30 07:04:32 host CEF:0|Security Events|ThreatAlert|869000350019695021|-SiteId (227349) bancaenlinea.bicsa.com -VisitCountry Germany|-RuleName Bad Bots|-ActionTakenRequest blocked |EntryPage bancaenlinea.bicsa.com/user/register//user/register/ -ClienteApp Chinese Vulnerability Scanner:1 -Ip 212.124.114.242-NumRequests 1 -AttemptedOn URL -AttackVectorInternalCode 200.0 may. 26 21:41:22 host CEF:0|Security Events|ThreatAlert|1000000270132476675|-SiteId (226911) www.bicsa.com -VisitCountry United States|-RuleName Bad Bots|-ActionTakenRequest blocked |EntryPage www.bicsa.com/robots.txt/robots.txt -ClienteApp LTX71:1 -Ip 35.226.23.240-NumRequests 1 -AttemptedOn URL -AttackVectorInternalCode 200.0 may. 27 17:13:21 host CEF:0|Security Events|ThreatAlert|432001330089612747|-SiteId (226911) www.bicsa.com -VisitCountry China|-RuleName Bad Bots|-ActionTakenRequest blocked |EntryPage www.bicsa.com/es/es -ClienteApp YisouSpider:1 -Ip 106.11.153.199-NumRequests 1 -AttemptedOn URL -AttackVectorInternalCode 200.0 may. 27 17:13:22 host CEF:0|Security Events|ThreatAlert|432001330089614196|-SiteId (226911) www.bicsa.com -VisitCountry China|-RuleName Bad Bots|-ActionTakenRequest blocked |EntryPage www.bicsa.com/robots.txt/robots.txt -ClienteApp YisouSpider:1 -Ip 106.11.155.219-NumRequests 2 -AttemptedOn URL -AttackVectorInternalCode 200.0 may. 27 17:13:22 host CEF:0|Security Events|ThreatAlert|432001330089614196|-SiteId (226911) www.bicsa.com -VisitCountry China -VisitCountry China|-RuleName Bad Bots|-ActionTakenRequest blocked |EntryPage www.bicsa.com/robots.txt/robots.txt -ClienteApp YisouSpider:1 -Ip 106.11.155.219-NumRequests 2/robots.txt -ClienteApp YisouSpider:1 -Ip 106.11.155.219-NumRequests 2 -AttemptedOn URL -AttackVectorInternalCode 200.0 may. 31 06:29:22 host CEF:0|Security Events|ThreatAlert|156000740014728873|-SiteId (226911) www.bicsa.com -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States -VisitCountry United States|-RuleName DDoS|-ActionTakenRequest suspended |EntryPage www.bicsa.com/www.bicsa.com/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1www.bicsa.com/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/robots.txt -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/pub/nuevo-formato-de-cheques/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/cuentas-corrientes/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/contacto/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/cobranzas/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/corporativa/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/finanzas-estructuradas/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/personal/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/ordenes-de-pago/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/ordenes-de-pago-2/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/certificado/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/e-banking/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/acerca-de-bicsa/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/infopersonal/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/bicsacapital/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/phishing/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/mapa-del-sitio/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/reportefraude/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/en/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/seguridad-y-privacidad/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1/servicios/ -ClienteApp Bot:1 -Ip 138.197.77.70-NumRequests 1 `; // 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