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𝕀

Mathematical Double-struck Small S Symbol

𝕀 is a mathematical double-struck small letter s used for formal typesetting.

U+1D564

The character 𝕀 is Unicode U+1D564, named MATHEMATICAL DOUBLE-STRUCK SMALL S. It’s commonly used when you want a distinct β€œdouble-struck” style in mathematical text. Use the copy options below for editors, web pages, and code.

Mathematical Double-struck Small S Symbol Meaning

𝕀 (Unicode U+1D564) is a β€œmathematical double-struck” lowercase s. The double-struck style is typically used in mathematics to distinguish a symbol from a regular italic or bold italic s. Depending on the author and context, it may appear in sets, algebra, or function/variable notation where a specific typographic convention matters. It’s most valuable when you need consistent, standards-based Unicode text rather than a styled approximation. When writing, pair it with surrounding symbols that match the same mathematical font style so the expression reads cleanly.

Common uses

  • β€’Denoting a special variable or parameter in math writing
  • β€’Labeling elements in a set or structured notation where typography must be consistent
  • β€’Creating homework, worksheets, or notes with Unicode math symbols
  • β€’Prototyping equations in chat, documentation, or plain-text environments
  • β€’Using a distinct symbol in research summaries and technical writing

Examples

𝕀 β€” Mathematical Double-Struck Small S

  • 𝕀Let 𝕀 be a parameter in the model.
  • 𝕀We define 𝕀(x) for x in the domain.
  • 𝕀For each 𝕀, compute the corresponding value.
  • 𝕀The expression uses 𝕀 to distinguish this case.
  • 𝕀Use 𝕀 alongside the other double-struck symbols.

Variations

Ready to copy

Technical codes

UnicodeU+1D564
HTML Entity𝕤
HTML Code𝕤
CSS\1D564

FAQ

What does the Mathematical Double-struck Small S symbol mean?

𝕀 (Unicode U+1D564) is a β€œmathematical double-struck” lowercase s. The double-struck style is typically used in mathematics to distinguish a symbol from a regular italic or bold italic s. Depending on the author and context, it may appear in sets, algebra, or function/variable notation where a specific typographic convention matters. It’s most valuable when you need consistent, standards-based Unicode text rather than a styled approximation. When writing, pair it with surrounding symbols that match the same mathematical font style so the expression reads cleanly.

What is the Unicode code point for 𝕀?

The character 𝕀 is U+1D564 (MATHEMATICAL DOUBLE-STRUCK SMALL S).

How do I copy 𝕀 into HTML?

You can use the HTML entity: 𝕤.

How do I type 𝕀 in CSS or JavaScript?

CSS escape: \\1D564. JavaScript (Unicode escape): \\u{1D564}.

Will 𝕀 display correctly on all devices?

It depends on font and system support for Unicode mathematical symbols. If it doesn’t render, try a Unicode/Math-capable font.