What ㌧ means
It writes the Japanese mass unit in one character. Unicode treats ㌧ as a compatibility form, so text processing can expand it to the ordinary Japanese spelling トン.
The Japanese character-set standard JIS X 0213 included it in its 2000 edition. That shows it was in the standard by then, not when the form was invented.
For ordinary Japanese prose, the JTF style guide lists t or トン for the unit as of 2026. A 2018 Japanese web explainer calls compact one-cell unit forms like this 組文字, a label for these composed characters, and describes strings of unit symbols as online wordplay.
Compact and typographic, with a Japanese legacy-character feel.
When ㌧ stands alone, start with the mass-unit reading.
Don't confuse it with
1Questions people ask
1Why does ㌧ show as a box on some devices?
Because that device's fonts have no glyph for it. The character is still correct and still copies correctly — the box is a missing glyph, not a broken character.
How to type ㌧
㌧\3327Codes and encoding1 code points
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.