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 = /lat/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('lat', 'gm') const str = `# Degrees minutes # \\d+\\W+\\d+\\W+\\d+\\.?\\d* "-77.566296, 41.471044" 5234098, 29384 40° 37' 03.620\\" N 39.9153 N 78.3405 W CORNPLANTER BRIDGE QUAD.--LAT. 41-48-18.41--LONG. -78-52-51.26 LUDLOW QUAD--LAT.41-39-16.0500--LONG.-78-55-11.1200 LAT 41-45-00 LONG 75-50-00 LAT 41.73381944 LONG -75.87685278 Ref Latitude 41 81833 - Ref Longitude -75 15167 LAT 41 56' 11.28\\" N--LON 76 52' 03.36\\" W [891] "McNett TOWNSHIP" [892] "TWP - Range - Sec" [893] "MONETT TOWNSHIP,LYCOMING COUNTY,PA LAT 41 42 12.6700 LAT 41 DEG 43-52-0300 LAT 41.4122917 Latitude: 40.752 N Lat. 40.72617600* N Longitude: 80-24-41 W Latitude: 40.653407 N LAT: 40.687574 LAT LAT: 40-50-13.7000 Latitude: 40.83721N LATITUDE Latitude 39-53-12.33 N LATITUDE 39-53.442319 N Latitude 39-53-43.26 N Latitude 39.8949 N LAT: 41-43-26.9600 N LAT: 41-43-29.83 LAT: 41*51'42.99\\" N LAT: 41-46-9.8700 N LATITUDE: 41* 42' 40.19\\" 41-42-40.19 LAT API # 37-015-208801-00--X=2201217.34E Y=632183.50N--LAT" 03-029-01`; // 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