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

/
/
gm

Test String

Code Generator

Language

Generated Code

const regex = /(?<=gps.longitude)(\s*)(:\s)(?<lon>.*)\n.*(?<=gps.latitude)(\s*)(:\s)(?<lat>.*)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?<=gps.longitude)(\\s*)(:\\s)(?<lon>.*)\\n.*(?<=gps.latitude)(\\s*)(:\\s)(?<lat>.*)', 'gm') const str = `modem.location.3gpp.mcc : 310 modem.location.3gpp.mnc : 260 modem.location.3gpp.lac : FFFE modem.location.3gpp.tac : 7D84 modem.location.3gpp.cid : 027A6B84 modem.location.gps.nmea.length : 5 modem.location.gps.nmea.value[1] : \$GPGSA,A,2,08,10,18,22,24,32,,,,,,,1.2,0.9,0.8*36 modem.location.gps.nmea.value[2] : \$GPRMC,194501.0,A,2947.759106,N,09534.022631,W,0.0,0.0,090922,3.2,E,A*15 modem.location.gps.nmea.value[3] : \$GPGSV,3,1,10,08,09,303,31,10,53,343,29,15,02,053,19,18,43,147,26*71\\r\\n\$GPGSV,3,2,10,22,31,239,31,24,34,057,29,27,23,268,21,31,00,196,19*76\\r\\n\$GPGSV,3,3,10,32,55,260,22,46,,,34*48 modem.location.gps.nmea.value[4] : \$GPVTG,0.0,T,356.8,M,0.0,N,0.0,K,A*2B modem.location.gps.nmea.value[5] : \$GPGGA,194501.0,2947.759106,N,09534.022631,W,1,06,0.9,28.1,M,-21.0,M,,*57 modem.location.gps.utc : 194501.0 modem.location.gps.longitude : -95.567044 modem.location.gps.latitude : 29.795985 modem.location.gps.altitude : 28.100000 modem.location.cdma-bs.longitude : -- modem.location.cdma-bs.latitude : --`; 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