Mathematical Bold Small I 𝐢
Visual Description: The character is a bold i. It looks like a regular i but thicker. In math fonts it carries a strong weight that helps it stand out in formulas. It is small in size, yet clear on lines and at inline positions.
Meaning & Usage: In bold math text, the letter i marks a variable or index. It signals emphasis without changing meaning. It helps separate text from variables in formulas and on calculators. Writers use it to denote a coordinate or element in arrays.
Historical Background: Bold math alphabets grew as part of a broader effort to distinguish variables by font. The practice appeared as fonts and typesetting tools evolved. The goal was to keep inline notation clear in dense formulas and on compact displays. The idea spread with digital typesetting and math editors.
Practical Use: It appears in formulas, calculators, and quick UI controls for operations or comparisons. Users may toggle bold weight to compare components, or switch between bold and regular to indicate emphasis. In software, bold i labels help users scan lists of variables and recognize indexed elements quickly.
See our category page for related symbols.
Look‑alikes: i (U+69).
Need styled alternatives? Try the Fancy Text tool.
Confusables
Technical details
- Codepoint:
U+1D422 - General Category:
Ll - Age:
3.1 - Bidi Class:
L - Decomposition:
<font> 0069 - Block:
Mathematical Alphanumeric Symbols - Script:
Common - UTF-8:
F0 9D 90 A2 - UTF-16:
D835 DC22 - UTF-32:
0001D422 - HTML dec:
𝐢 - HTML hex:
𝐢 - JS escape:
\u{1D422} - Python \N{}:
\N{MATHEMATICAL BOLD SMALL I} - Python \U:
\U0001D422 - URL-encoded:
%F0%9D%90%A2 - CSS escape:
\1D422
How to type / insert
Fast copy: click the Copy button near the top of this page.
By codepoint: in many editors and IDEs, you can insert via the Unicode code U+1D422 or a built‑in character picker.
HTML: use the numeric entity 퐢 (hex) or 퐢 (decimal) when an HTML entity is needed.
Compatibility & troubleshooting
Font support: if the symbol does not render, the current font likely lacks this codepoint. Choose a font with broad Unicode coverage or allow a fallback font.
Web pages: ensure your CSS font stack includes a general fallback; avoid relying on images for common symbols to preserve accessibility and copyability.