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

/
/
g

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

const regex = /(?<=[.?!;]|[.!?][\'"”])(?<!Mr\.|Mrs\.|Ms\.|Jr\.|Dr\.|Ir\.|Prof\.|\.\.|\.\.\.|Sr\.|T\.V\.A\.)\s+(?=\p{Lu}|[“"])/g; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?<=[.?!;]|[.!?][\\\'"”])(?<!Mr\\.|Mrs\\.|Ms\\.|Jr\\.|Dr\\.|Ir\\.|Prof\\.|\\.\\.|\\.\\.\\.|Sr\\.|T\\.V\\.A\\.)\\s+(?=\\p{Lu}|[“"])', 'g') const str = `Maher Zain is a global sensation. With 22 million Facebook fans — that’s more than Madonna — he is by far the biggest name in Islamic music today. “I’m so scared,” he says. “What if one morning I just wake up,” he clicks his fingers, “and boom, my intentions change. What if I’m no longer the same person? It scares me a lot.” Zain is sitting in the back of a bus that is taking him to perform in Glasgow. Touring Britain with the charity Human Appeal, visiting 11 cities, along with three other artists from his record label, Awakening Records, he is concerned that one day his fame could overwhelm him. Right now, however, there are no signs to suggest that. In fact, the opposite is true: despite two multi-platinum albums, hundreds of millions of views on Youtube, and even knocking Justin Bieber off top spot with his debut album in Indonesia, he is as grounded as ever. In 2007, Zain, a Lebanese-born Swedish musician, was in the United States, preparing for the next stage of his career.`; const subst = `\n`; // The substituted value will be contained in the result variable const result = str.replace(regex, subst); console.log('Substitution result: ', result);

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