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

/
/
gmi

Test String

Code Generator

Generated Code

const regex = /(((mr|prof|dr|mrs|ms)\.\s\w+,?)|\w\.\w\.)/gmi; // Alternative syntax using RegExp constructor // const regex = new RegExp('(((mr|prof|dr|mrs|ms)\\.\\s\\w+,?)|\\w\\.\\w\\.)', 'gmi') const str = `In in aliquet turpis. Donec pretium sodales metus mollis consequat! Sed non bibendum neque? Suspendisse hendrerit vel erat non cursus. Aenean eget lectus nulla. Mauris quam nulla, hendrerit ac congue gravida, interdum sit amet erat. I am the one that sees the dawn. See you at 5 P.M. tomorrow. Ut vulputate leo sit amet turpis bibendum malesuada. Mr. Brown, Prof. Plumb and Ms. Scarlet all had thier reasons. Aliquam erat volutpat. Sed at feugiat dolor, quis bibendum magna. Donec sed neque eu ipsum eleifend accumsan. "What that just isn't true .... no" Quisque eu volutpat tellus, in hendrerit libero. Phasellus ac fermentum turpis. Nulla ullamcorper, justo placerat pulvinar scelerisque, justo elit gravida metus, nec tristique nisl purus eu leo. In the year of our lord 2018 the people on earth where content in their unhappiness, oblivious of the inevitability of damnantion. Asteroid ABV30004-442-23212-NONE A sentense that ends oddly Mr. Suspendisse semper posuere faucibus. Etiam ligula augue, pharetra ut massa ac, sodales faucibus augue. Duis dignissim felis et urna commodo, eget laoreet libero consectetur. Nam felis velit, efficitur et tortor in, molestie egestas erat. Nullam id metus nec ex mollis molestie quis in justo. Cras nec quam sem. Ut luctus in nibh sed molestie. Praesent ut "dapibus ex suspendisse" potenti. Curabitur consequat turpis at aliquam molestie.`; // 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