Full-width & Half-width Converter

Convert full-width and half-width text

Paste text on the left, pick a direction, and the converted text appears instantly. Use as input moves the result back to the input, so you can flip between the two directions without retyping anything.

Four modes are available, grouped by scope:

• Full-width to half-width and half-width to full-width convert everything the tool knows about.
• Punctuation to half-width and punctuation to full-width convert only punctuation, symbols, and spaces, leaving letters, digits, and kana alone.

What gets converted

A half-width kana followed by a voiced mark is composed on the way in: ｶ plus ﾞ becomes ガ, and ﾊ plus ﾟ becomes パ. Narrowing splits it back into kana plus mark, so the two directions round-trip exactly. A mark that follows nothing is left alone.

Both directions are exact inverses, so converting back and forth never loses a character.

What stays unchanged

Characters without a half-width counterpart are left untouched, because rewriting them would lose information: hiragana (including the voiced ゔ and ん), kanji, half-width Hangul, ideographic punctuation such as 《》 and …, and spaces outside the active conversion scope.

Privacy

Everything runs in your browser. No text is uploaded.