Superscripts and Subscripts

• Define a clear semantic usage: mark superscripts for footnotes, exponents, or chemical formulas; keep subscripts for chemical formulas or indexing in math.
• Use font features or CSS to control size and baseline independently for consistent rendering across platforms.
• Avoid mixing superscripts/subscripts with line breaks; prefer wrapping them in inline elements for stable layout.
• Test across fonts and devices to ensure glyph availability and consistent spacing.
• Provide accessible fallbacks, such as descriptive labels or long alt text when the meaning isn’t obvious from context.

Superscripts and subscripts are a long-standing typographic tool. They let you show notation without changing the main text flow. In design, they support concise equations, chemical formulas, and footnotes.

Typical usage centers on inline mathematics, scientific notation, and references. Common pitfalls include inconsistent baseline shifts, poor font support, and accessibility gaps for screen readers. Historically, these glyphs evolved from traditional math typesetting and have become a standard feature in digital typography, with styles that adapt to web and app design while preserving readability. For related topics, see Geometric shapes, Arrows, Currency symbols, and Box drawing.