Halfwidth Small Tsu

Enter small tsu, then select halfwidth Katakana.

In a Japanese input method, enter xtsu or ltsu for small っ; inside a word, doubling the next consonant also works (gakkou → がっこう). Convert to Katakana, then select halfwidth output. Microsoft Japanese IME uses F8 for that conversion.

For a standalone ｯ, enter xtsu → ッ and convert to halfwidth. Plain tsu produces full-size つ or ツ.

What does ｯ mean in Japanese?

It marks a brief closure before the next consonant.

This is the halfwidth counterpart of ッ, the Katakana sokuon. It has no independent “tsu” vowel: in ｶﾞｯｺｳ, it marks the closure before k; at the end of ｱｯ, it can give an interjection a clipped stop.

Sokuon-related writing is documented from the Heian period. Early spellings varied or omitted the mark; ツ/つ notation was broadly settled by the late Heian period, and small writing became general after World War II. In Ainu writing, related small-kana forms can mark word-final consonants; that is a different use from Japanese ｯ.

Why does ｯ look different from ッ?

The difference is width and encoding history, not pronunciation.

ｯ is a compatibility-width form of ッ. NFKC normalization can change it to ッ; NFC preserves the distinction. In fixed-pitch East Asian fonts, a halfwidth character takes about half an em.

JIS X 0201, established in 1969, included Japanese Katakana in a single-byte character set for older systems. ISO-2022-JP cannot carry halfwidth kana. Ordinary Japanese prose uses ッ; a particular field may require a specific width.