What 𝒿 means
It is a script-style j whose formula supplies its role. Mathematical notation can use a change of letter style to make the script j a distinct symbol, not just a decorated version of the same letter.
A medieval arithmetic book, Leonardo of Pisa’s Liber abbaci (1202), already used small Latin letters for given numbers. A 1999 proposal to Unicode describes script among styles already used in scientific publishing, where changing a letter’s style could change its mathematical meaning. The proposal sought a systematic alphabet alongside a smaller set of special mathematical letter forms already in use.
Why does 𝒿 look different in math fonts?
The selected math font supplies its exact script shape. Unicode 16.0 shows a roundhand chart form, while noting that Cambria Math and STIX Two Math default to chancery forms. The same mathematical script letter can therefore look rounder or more formal depending on the font.
Part of the collection
Don't confuse it with
2
Related characters
2
Questions people ask
1Why does 𝒿 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.
More like this
11
How to type or find 𝒿
- Search it as
- mathscr j · script j · calligraphic j · curly j · fancy j
- Shows up in
- Anything that takes text · its shape is whatever your font draws
𝒿\1D4BF𝒿 as a hexadecimal numeric character reference.Codes and encoding1 code points
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.