What 𝙳 means
The formula sets its role; monospace separates it from other styles.
In one formula, plain and styled Ds can stand for different things; the writer's notation decides.
The fuller mathematical alphabets grew from a smaller, older collection of letter-shaped math symbols, letting formulas preserve style distinctions in plain text. Using them as decoration is a side effect.
At home in math and technical notation.
In prose, it can hinder search and accessibility-friendly restyling.
Don't confuse it with
4𝗗𝘋𝘿𝙰
Mathematical Sans-Serif Bold Capital D
shares “capital”, “d”, “mathematical”
Mathematical Sans-Serif Italic Capital D
shares “capital”, “d”, “mathematical”
Mathematical Sans-Serif Bold Italic Capital D
shares “capital”, “d”, “mathematical”
Mathematical Monospace Capital A
shares “capital”, “mathematical”, “monospace”
Questions people ask
1Does NFKC keep 𝙳 distinct from D?
No. NFKC is a Unicode text-cleanup rule that folds compatible style variants to plain letters; it turns 𝙳 into D.
How to type 𝙳
Windows (Word)
Alt+XType 1D673, then Alt+X to get 𝙳.
Windows
Win+Rrun charmap for the full table, or use the emoji picker's Ω symbols tab (Win + .).
macOS
Control+Command+SpaceOpen the character viewer and search “mathematical monospace capital d”.
Linux
Ctrl+Shift+UType 1d673, then Enter or Space.
HTML
𝙳CSS
\1D673Codes and encoding1 code points
HTML decimal
𝙳
HTML hex
𝙳
CSS content
content: "\1D673";
Each escape is closed by the next backslash; a trailing space is needed before a literal hex digit.
URL encoded
%F0%9D%99%B3
1
On screen
1
Code points
2
JS .length
4
UTF-8 bytes
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.