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

/
/

Test String

Code Generator

Language

Generated Code

const regex = /(1) (\d{5})([US ]) (\d{2})(\d{3})([A-Z ]{1,3}) (\d{2})(\d.{11}) ([-].\d{8}) ([-+ ]\d{5}[-+ ]\d) ([-+ ]\d{5}[-+]\d) ([0-4]) ([ \d]{4})(\d) (2) (\d{5}) ([ \d]{3}.[\d ]{4}) ([ \d]{3}.[ \d]{4}) (\d{7}) ([ \d]{3}.[\d ]{4}) ([ \d]{3}.[\d ]{4}) ([ \d]{2}.[\d ]{8})([ \d]{5})(\d)/; // Alternative syntax using RegExp constructor // const regex = new RegExp('(1) (\\d{5})([US ]) (\\d{2})(\\d{3})([A-Z ]{1,3}) (\\d{2})(\\d.{11}) ([-].\\d{8}) ([-+ ]\\d{5}[-+ ]\\d) ([-+ ]\\d{5}[-+]\\d) ([0-4]) ([ \\d]{4})(\\d) (2) (\\d{5}) ([ \\d]{3}.[\\d ]{4}) ([ \\d]{3}.[ \\d]{4}) (\\d{7}) ([ \\d]{3}.[\\d ]{4}) ([ \\d]{3}.[\\d ]{4}) ([ \\d]{2}.[\\d ]{8})([ \\d]{5})(\\d)', '') const str = `1 25544S 98067A 98324.28472222 -.00003657 11563-4 00000+0 0 10 2 25544 51.5908 168.3788 0125362 86.4185 359.7454 16.05064833 05`; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; if ((m = regex.exec(str)) !== null) { // 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