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

/
/
mg

Test String

Code Generator

Language

Generated Code

const regex = /^(([NnSs+-])?([0-8]?\d(\.\d*)?|90(\.0*)?)([°˚º^~*NnSs+-])*)([,:;\s|\/\\-]+)(([EeWw+-])*([0]?\d?\d(\.\d*)?|1[0-7]\d(\.\d*)?|180(\.0*)?)[°˚º^~*]*([EeWw+-])*)[\s]*$/mg; // Alternative syntax using RegExp constructor // const regex = new RegExp('^(([NnSs+-])?([0-8]?\\d(\\.\\d*)?|90(\\.0*)?)([°˚º^~*NnSs+-])*)([,:;\\s|\\\/\\\\-]+)(([EeWw+-])*([0]?\\d?\\d(\\.\\d*)?|1[0-7]\\d(\\.\\d*)?|180(\\.0*)?)[°˚º^~*]*([EeWw+-])*)[\\s]*$', 'mg') const str = `//check all zeros 0 0 0.0 0.0 0.000 0.000 0.0000 0.0000 //check plus and minus signs +0 0 +0.0 0.0 +0.000 0.000 +0.0000 0.0000 0 +0 0.0 +0.0 0.000 +0.000 0.0000 +0.0000 +0 +0 +0.0 +0.0 +0.000 +0.000 +0.0000 +0.0000 -0 0 -0.0 0.0 -0.000 0.000 -0.0000 0.0000 0 -0 0.0 -0.0 0.000 -0.000 0.0000 -0.0000 -0 -0 -0.0 -0.0 -0.000 -0.000 -0.0000 -0.0000 0+ 0 0.0+ 0.0 0.000+ 0.000 0.0000+ 0.0000 0 0+ 0.0 0.0+ 0.000 0.000+ 0.0000 0.0000+ 0- 0 0.0- 0.0 0.000- 0.000 0.0000- 0.0000 0 0- 0.0 0.0- 0.000 0.000- 0.0000 0.0000- 0+ 0+ 0.0+ 0.0+ 0.000+ 0.000+ 0.0000+ 0.0000+ 0- 0- 0.0- 0.0- 0.000- 0.000- 0.0000- 0.0000- //check hemipshere 0N 0 0.0N 0.0 0.000N 0.00 0.0000N 0.000 0N 0E 0.0N 0.0E 0.000N 0.00E 0.0000N 0.000E 0N 0W 0.0N 0.0W 0.000N 0.00W 0.0000N 0.000W 0S 0 0.0S 0 0.000S 0 0.0000S 0 0S 0E 0.0S 0.0E 0.000S 0.00E 0.0000S 0.000E 0S 0W 0.0S 0.0W 0.000S 0.00W 0.0000S 0.000W //check degree symbols 0° 0° 0.0° 0.0° 0.000° 0.000° 0.0000° 0.0000° 0˚ 0˚ 0.0˚ 0.0˚ 0.000˚ 0.000˚ 0.0000˚ 0.0000˚ 0º 0º 0.0º 0.0º 0.000º 0.000º 0.0000º 0.0000º 0^ 0^ 0.0^ 0.0^ 0.000^ 0.000^ 0.0000^ 0.0000^ 0* 0* 0.0* 0.0* 0.000* 0.000* 0.0000* 0.0000* 0~ 0~ 0.0~ 0.0~ 0.000~ 0.000~ 0.0000~ 0.0000~ //check sperators 0,0 0.0,0.0 0.000,0.000 0.0000,0.0000 0-0 0.0-0.0 0.000-0.000 0.0000-0.0000 0:0 0.0:0.0 0.000:0.000 0.0000:0.0000 0;0 0.0;0.0 0.000;0.000 0.0000;0.0000 0|0 0.0|0.0 0.000|0.000 0.0000|0.0000 0/0 0.0/0.0 0.000/0.000 0.0000/0.0000 0\\0 0.0\\0.0 0.000\\0.000 0.0000\\0.0000 90,180 45,45 //invalid 90.123 0.0 91.0 0 91.00 0 91.0 0.0 91.00 0.00 0 180.1 0 181 `; // 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