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

/
/
gm

Test String

Code Generator

Language

Generated Code

const regex = /"(?:[Aa]uthor[s]?|[Jj]ournalist|[Pp]erson)":(?:{(?:[^}[]+)?"name[s]?":\[?(?:"name":)?"|")([^"\\]+)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('"(?:[Aa]uthor[s]?|[Jj]ournalist|[Pp]erson)":(?:{(?:[^}[]+)?"name[s]?":\\[?(?:"name":)?"|")([^"\\\\]+)', 'gm') const str = `"author":"Lucy Bode","publisher":{"name":"Channel Void" "author":{"name":"Lucy Bode"},"publisher":{"name":"Channel Void" "author":{"names":["Lucy Bode"]},"publisher":{"name":"Channel Void" "author":{"names":["name":"Lucy Bode"]},"publisher":{"name":"Channel Void" "author":{"names":["Lucy Bode"]},"publisher":{"name":"Channel Void" "journalist":"Lucy Bode","publisher":{"name":"Channel Void" "journalist":{"names":["Lucy Bode"]},"publisher":{"name":"Channel Void" "journalist":{"names":["name":"Lucy Bode"]},"publisher":{"name":"Channel Void" "journalist":{"names":["Lucy Bode"]},"publisher":{"name":"Channel Void" "authors":"Lucy Bode","publisher":{"name":"Channel Void" "authors":{"name":"Lucy Bode"},"publisher":{"name":"Channel Void" "authors":{"names":["Lucy Bode"]},"publisher":{"name":"Channel Void" "authors":{"names":["name":"Lucy Bode"]},"publisher":{"name":"Channel Void" "authors":{"names":["Lucy Bode"]},"publisher":{"name":"Channel Void" "person":{"name":"Lucy Bode"},"publisher":{"name":"Channel Void" "person":{"names":["Lucy Bode"]},"publisher":{"name":"Channel Void" "person":{"names":["name":"Lucy Bode"]},"publisher":{"name":"Channel Void" "person":{"names":["Lucy Bode"]},"publisher":{"name":"Channel Void" "Person":{"name":"Lucy Bode"},"publisher":{"name":"Channel Void" "Person":{"names":["Lucy Bode"]},"publisher":{"name":"Channel Void" "Person":{"names":["name":"Lucy Bode"]},"publisher":{"name":"Channel Void" "Person":{"names":["Lucy Bode"]},"publisher":{"name":"Channel Void" "author":{"@type":"Person","name":"Lucy Bode"} "image":{"@type":"ImageObject","url":"https://static.nationalgeographic.co.uk/files/styles/image_3200/public/rewilding-redonda.jpg?w=1900&h=1267","width":1900,"height":1267,"author":{"@type":"Person","name":"Ed Marshall, Redonda Restoration Programme"},`; // 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