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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

/
/
igm

Test String

Code Generator

Language

Generated Code

const regex = /<tagname((.|\n)(?!string))*?<\/tagname>/igm; // Alternative syntax using RegExp constructor // const regex = new RegExp('<tagname((.|\\n)(?!string))*?<\\\/tagname>', 'igm') const str = `<?xml version="1.0" encoding="utf-8"?> <OdfBody Source="IDS" DocumentCode="EQ0000000" Serial="869" Time="104139151" CompetitionCode="PG2016" Date="2016-09-02" FeedFlag="P" LogicalDate="2016-09-02" DocumentType="DT_PARTIC" Version="3" > <Competition Code="PG2016"> <Participant Parent="1057257" MainFunctionId="AA01" OlympicSolidarity="N" Organisation="AUT" Code="1057257" BirthDate="1977-12-15" Nationality="AUT" Status="ACTIVE" TVName="Michael Martin KNAUDER" GivenName="Michael Martin" Gender="M" TVInitialName="M.M. KNAUDER" FamilyName="KNAUDER" PrintName="KNAUDER Michael Martin" PrintInitialName="KNAUDER MM" Current="true"> <Discipline IFId="10081843" Code="EQ"> <RegisteredEvent Event="001" Class="GIA" Gender="X"> <EventEntry Value="H014452" Type="ENTRY" Code="HORSE_ID"/> <EventEntry Value="P 7" Type="ENTRY" Code="PROFILE"/> </RegisteredEvent> <RegisteredEvent Event="401" Class="GIA" Gender="X"> <EventEntry Value="H014452" Type="ENTRY" Code="HORSE"/> <EventEntry Value="P 7" Type="ENTRY" Code="PROFILE"/> </RegisteredEvent> <RegisteredEvent Event="420" Class="GIA" Gender="X"> <EventEntry Value="H014452" Type="ENTRY" Code="HORSE_ID"/> <EventEntry Value="P 7" Type="ENTRY" Code="PROFILE"/> </RegisteredEvent> </Discipline> </Participant> <Participant Parent="1063065" MainFunctionId="TM_OFFIC" OlympicSolidarity="N" Organisation="CZE" Code="1063065" BirthDate="1974-10-28" Nationality="CZE" Status="ACTIVE" TVName="Lenka MATOSKOVA" GivenName="Lenka" Gender="W" TVInitialName="L. MATOSKOVA" FamilyName="MATOSKOVA" PrintName="MATOSKOVA Lenka" PrintInitialName="MATOSKOVA L" Current="true"> <Discipline Code="EQ"/> </Participant> <Participant Parent="1096278" MainFunctionId="AA01" OlympicSolidarity="N" Organisation="AUT" Code="1096278" BirthDate="1995-09-24" Nationality="AUT" Status="ACTIVE" TVName="Julia SCIANCALEPORE" GivenName="Julia" Gender="W" TVInitialName="J. SCIANCALEPORE" FamilyName="SCIANCALEPORE" PrintName="SCIANCALEPORE Julia" PrintInitialName="SCIANCALEPORE J" Current="true"> <Discipline IFId="10108391" Code="EQ"> <RegisteredEvent Event="001" Class="GIA" Gender="X"> <EventEntry Value="H014366" Type="ENTRY" Code="HORSE_ID"/> <EventEntry Value="P 12a" Type="ENTRY" Code="PROFILE"/> </RegisteredEvent> <RegisteredEvent Event="401" Class="GIA" Gender="X"> <EventEntry Value="H014366" Type="ENTRY" Code="HORSE"/> <EventEntry Value="P 12a" Type="ENTRY" Code="PROFILE"/> </RegisteredEvent> <RegisteredEvent Event="420" Class="GIA" Gender="X"> <EventEntry Value="H014366" Type="ENTRY" Code="HORSE_ID"/> <EventEntry Value="P 12a" Type="ENTRY" Code="PROFILE"/> </RegisteredEvent> </Discipline> </Participant> </Competition> </OdfBody>`; // 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