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

Substitution

Processing...

Code Generator

Language

Generated Code

const regex = /(?sx)([ぁ-ゔ])(?=.*:\1=(.))/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?sx)([ぁ-ゔ])(?=.*:\\1=(.))', 'gm') const str = `このビルディングのベースメントはレストランとカフェがあります。 Dictionary:ぁ=ァ:あ=ア:ぃ=ィ:い=イ:ぅ=ゥ:う=ウ:ぇ=ェ:え=エ:ぉ=ォ:お=オ:か=カ:が=ガ:き=キ:ぎ=ギ:く=ク:ぐ=グ:け=ケ:げ=ゲ:こ=コ:ご=ゴ:さ=サ:ざ=ザ:し=シ:じ=ジ:す=ス:ず=ズ:せ=セ:ぜ=ゼ:そ=ソ:ぞ=ゾ:た=タ:だ=ダ:ち=チ:ぢ=ヂ:っ=ッ:つ=ツ:づ=ヅ:て=テ:で=デ:と=ト:ど=ド:な=ナ:に=ニ:ぬ=ヌ:ね=ネ:の=ノ:は=ハ:ば=バ:ぱ=パ:ひ=ヒ:び=ビ:ぴ=ピ:ふ=フ:ぶ=ブ:ぷ=プ:へ=ヘ:べ=ベ:ぺ=ペ:ほ=ホ:ぼ=ボ:ぽ=ポ:ま=マ:み=ミ:む=ム:め=メ:も=モ:ゃ=ャ:や=ヤ:ゅ=ュ:ゆ=ユ:ょ=ョ:よ=ヨ:ら=ラ:り=リ:る=ル:れ=レ:ろ=ロ:ゎ=ヮ:わ=ワ:ゐ=ヰ:ゑ=ヱ:を=ヲ:ん=ン:ゔ=ヴ:ヵ=ヵ:ヶ=ヶ:わ゙=ヷ:ゐ゙=ヸ:ゑ゙=ヹ:ヺ=ヺ`; const subst = `$2`; // 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