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

/
/
igm

Test String

Code Generator

Generated Code

const regex = /(.+?([A-Z].)\.(?:['")\\\s]?)+?\s?)/igm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(.+?([A-Z].)\\.(?:[\'")\\\\\\s]?)+?\\s?)', 'igm') const str = `If he's restin', I'll wake him up! (Shouts at the cage.) 'Ello, Mister Polly Parrot! (Owner hits the cage.) There, he moved!!!\\r\\n\\r\\nNorth Korea is accusing the U.S. government of being behind the making of the movie \\"The Interview.\\"\\r\\n\\r\\nAnd, in a dispatch on state media, the totalitarian regime warns the United States that U.S. \\"citadels\\" will be attacked, dwarfing the attack on Sony that led to the cancellation of the film's release.\\r\\n\\r\\nWhile steadfastly denying involvement in the hack, North Korea accused U.S. President Barack Obama of calling for \\"symmetric counteraction.\\"\\r\\n\\r\\n\\"The DPRK has already launched the toughest counteraction. Nothing is more serious miscalculation than guessing that just a single movie production company is the target of this counteraction. Our target is all the citadels of the U.S. imperialists who earned the bitterest grudge of all Koreans,\\" a report on state-run KCNA read."`; // 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