What ℬ means
Read it by the formula's definitions, not by its shape alone.
In 1591, François Viète made a major step in algebra by using capital Latin letters for known and unknown quantities, with consonants such as B for known values. Separately, Jacques Binet recorded ordinary B(p,q) for the beta function in 1839. These are histories of algebraic letters and beta notation, not origin dates for the exact script glyph.
Part of the collection
Don't confuse it with
3
Cyrillic Capital Letter Ve
Looks identical to Latin B in most fonts; a common spoofing trick in web addresses and names.
Greek Capital Letter Beta
Looks like Latin B in most fonts; mixing it into a word breaks search and copy matching.
Ｂ
Fullwidth Latin Capital Letter B
Fullwidth Latin Capital B, from CJK input methods. Same letter shape at a wider width, but a different code point for search.
Related characters
2
Questions people ask
1Why does ℬ 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
13
How to type or find ℬ
- Search it as
- calligraphic B · script B in math · Bernoulli function symbol · ℬ formula meaning
- Shows up in
- Anything that takes text · its shape is whatever your font draws
Codes and encoding1 code points
HTML decimal
ℬ
HTML hex
ℬ
CSS content
content: "\212C";
Each escape is closed by the next backslash; a trailing space is needed before a literal hex digit.
URL encoded
%E2%84%AC
1
On screen
1
Code points
1
JS .length
3
UTF-8 bytes
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.