What 𝑏 means
It is an identifier whose role varies from formula to formula. Mathematical notation developed through several conventions: François Viète used upright capitals for unknowns in 1591; René Descartes' geometry book La Géométrie established lowercase italic unknowns in 1637, using early letters for constants and later letters for variables. This math italic b follows that single-letter tradition; in scientific notation, variable b may name a quantity or a parameter held constant for that problem.
Why does 𝑏 become plain b?
Compatibility normalization removes its mathematical style. Unicode's 1999 proposal treated math-letter styles as meaningful distinctions: changing style can change a symbol's meaning. NFKC normalization maps 𝑏 to ordinary b, discarding that distinction. Use ordinary b with italic formatting in prose; this dedicated mathematical alphabet is intended for mathematical or technical notation.
Part of the collection
Don't confuse it with
3
Related characters
1
Questions people ask
1Can MathML italicize ordinary b without 𝑏?
Yes. MathML, a format for structuring equations on the web, can set mathvariant="italic" on ordinary b, expressing the math-italic style through markup instead of a separate character.
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How to type or find 𝑏
- Search it as
- italic b · variable b · fancy b · unicode b · slanted b · b character
- Shows up in
- Anything that takes text · its shape is whatever your font draws
𝑏\1D44F1D44F then Alt+X; if the code follows text, select only the code first. Checked in 2026.Codes and encoding1 code points
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.