The Unicode Subscript Character Set — Explained

Unicode's subscript characters are concentrated in the Superscripts and Subscripts block (U+2070–U+209F). This block was specifically designed to provide plain-text alternatives to HTML <sub> formatting — glyphs that appear below the baseline without requiring any markup or rich text environment.

The block contains 10 subscript digits (₀–₉, U+2080–U+2089), 5 arithmetic operators (₊ ₋ ₌ ₍ ₎, U+208A–U+208E), and 13 Latin letters (ₐₑₒₓₔₕₖₗₘₙₚₛₜ, U+2090–U+209C). Additional subscript-height letters exist in the Phonetic Extensions block (U+1D00–U+1DBF) and Modifier Letter blocks, primarily for International Phonetic Alphabet (IPA) use.

A critical point for users: the full 26-letter Latin subscript alphabet does not exist in Unicode. Only 14 letters have dedicated subscript code points. For full-alphabet small text rendering, Unicode small caps characters (from the Phonetic Extensions block) are the practical alternative — they cover the full alphabet and appear in a reduced style, though not technically "below the baseline" like true subscript.