Mathematical Double-Struck Small U 𝕦

Visual Description: The character is a small u rendered in a double-struck style, with two vertical strokes on each side. It looks like a regular letter that has been dressed up for math. In interfaces, it appears at standard font sizes and keeps clear edge lines.

Meaning & Usage: It functions as a typographic variant. Writers use it to distinguish a variable, a set, or a special object in a formula. In calculators and editors, it signals a chosen style rather than a new numeric value. It relies on audience convention for interpretation.

Historical Background: The double-struck style grew from a practical need to mark distinct mathematical objects. It became part of a broader family of symbols used to separate meaning through typography. The idea travels through textbooks and software, where fonts carry context and help avoid misreading in dense equations.

Practical Use: In math tools, you can apply this style with a quick UI control to show a variable in double-struck form. It supports formulas, comparisons, and notation groups. Users switch fonts, toggle emphasis, and input the symbol in place of a normal u when needed.

See our category page for related symbols.

Look‑alikes: u (U+75).

Need styled alternatives? Try the Fancy Text tool.