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

/
/
u

Test String

Code Generator

Language

Generated Code

const regex = /[^\x{0009}\x{000A}\x{000D}\x{0020}-\x{007E}\x{0085}\x{00A0}-\x{D7FF}\x{E000}-\x{FDCF}\x{FDE0}-\x{FFFD}\x{10000}-\x{1FFFD}\x{20000}-\x{2FFFD}\x{30000}-\x{3FFFD}\x{40000}-\x{4FFFD}\x{50000}-\x{5FFFD}\x{60000}-\x{6FFFD}\x{70000}-\x{7FFFD}\x{80000}-\x{8FFFD}\x{90000}-\x{9FFFD}\x{A0000}-\x{AFFFD}\x{B0000}-\x{BFFFD}\x{C0000}-\x{CFFFD}\x{D0000}-\x{DFFFD}\x{E0000}-\x{EFFFD}\x{F0000}-\x{FFFFD}\x{100000}-\x{10FFFD}]/u; // Alternative syntax using RegExp constructor // const regex = new RegExp('[^\\x{0009}\\x{000A}\\x{000D}\\x{0020}-\\x{007E}\\x{0085}\\x{00A0}-\\x{D7FF}\\x{E000}-\\x{FDCF}\\x{FDE0}-\\x{FFFD}\\x{10000}-\\x{1FFFD}\\x{20000}-\\x{2FFFD}\\x{30000}-\\x{3FFFD}\\x{40000}-\\x{4FFFD}\\x{50000}-\\x{5FFFD}\\x{60000}-\\x{6FFFD}\\x{70000}-\\x{7FFFD}\\x{80000}-\\x{8FFFD}\\x{90000}-\\x{9FFFD}\\x{A0000}-\\x{AFFFD}\\x{B0000}-\\x{BFFFD}\\x{C0000}-\\x{CFFFD}\\x{D0000}-\\x{DFFFD}\\x{E0000}-\\x{EFFFD}\\x{F0000}-\\x{FFFFD}\\x{100000}-\\x{10FFFD}]', 'u') const str = `<bad> </bad>`; // 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