Unicode has subscripted and superscripted versions of a number of characters including a full set of Arabic numerals.^{[1]} These characters allow any polynomial, chemical and certain other equations to be represented in plain text without using any form of markup like HTML or TeX.
The World Wide Web Consortium and the Unicode Consortium have made recommendations on the choice between using markup and using superscript and subscript characters:
When used in mathematical context (MathML) it is recommended to consistently use style markup for superscripts and subscripts.... However, when super and subscripts are to reflect semantic distinctions, it is easier to work with these meanings encoded in text rather than markup, for example, in phonetic or phonemic transcription.^{[2]}
The intended use^{[2]} when these characters were added to Unicode was to allow chemical and algebra formulas and phonetics to be written without markup, but produce true superscripts and subscripts. Thus "H₂O" (using a subscript character) is supposed to be identical to "H_{2}O" (with subscript markup).
In reality most fonts that include these characters ignore the Unicode definition, and design the digits for mathematical numerator and denominator glyphs,^{[3]}^{[4]} which are smaller than normal characters but are aligned with the cap line and the baseline, respectively. When used with the solidus, these glyphs are useful for making arbitrary diagonal fractions (similar to the ½ glyph). Making fractions using existing software super/subscripts requires many characters and does not look like the rendered fraction (example: ^{1}/_{2}), so font designers provided this alternative. This also makes the superscript letters useful for ordinal indicators, more closely matching the ª and º characters. However it makes them incorrect for normal super and subscripts, and formulas are rendered correctly by using markup rather than these characters.
Unicode intended to produce diagonal fractions through a different mechanism but it is very poorly supported. The fraction slash U+2044 is visually similar to the solidus, but when used with the ordinary digits (not the superscripts and subscripts) is intended to tell a layout system that a fraction such as ¾ should be rendered^{[5]} using automatic glyph substitution^{[a]} for the digits. Some browsers support this^{[b]} but not in all fonts. A selection of fonts is shown in the below table.
Characters  Font  Result 

U+00BD ½ VULGAR FRACTION ONE HALF  Default  ½ 
U+00B9 ¹ SUPERSCRIPT ONE, U+002F / SOLIDUS, U+2082 ₂ SUBSCRIPT TWO  ¹/₂  
U+00B9 ¹ SUPERSCRIPT ONE, U+2044 ⁄ FRACTION SLASH, U+2082 ₂ SUBSCRIPT TWO  ¹⁄₂  
U+0031 1 DIGIT ONE, U+2044 ⁄ FRACTION SLASH, U+0032 2 DIGIT TWO 
1⁄2  
Arial  1⁄2  
Cambria  1⁄2  
Consolas  1⁄2  
Times New Roman  1⁄2  
FiraGO  1⁄2  
EB Garamond  1⁄2  
Cantarell  1⁄2  
Lato  1⁄2  
Linux Libertine O  1⁄2  
Nimbus Roman  1⁄2  
Ubuntu  1⁄2  
Yrsa  1⁄2 
Main article: Superscripts and Subscripts (Unicode block) 
The most common superscript digits (1, 2, and 3) were in ISO88591 and were therefore carried over into those positions in the Latin1 range of Unicode. The rest were placed in a dedicated section of Unicode at U+2070 to U+209F. The two tables below show these characters. Each superscript or subscript character is preceded by a normal x to show the subscripting/superscripting. The table on the left contains the actual Unicode characters; the one on the right contains the equivalents using HTML markup for the subscript or superscript.


Unicode version 15.0 also includes subscript and superscript characters that are intended for semantic usage, in the following blocks:^{[1]}^{[6]}
See also: superscript IPA letters 
Consolidated, the Unicode standard contains superscript and subscript versions of a subset of Latin, Greek and Cyrillic letters. Here they are arranged in alphabetical order for comparison (or for copy and paste convenience). Since these characters appear in different Unicode ranges, they may not appear to be the same size or position due to font substitution in the browser. Shaded cells mark small capitals that are not very distinct from minuscules, and Greek letters that are indistinguishable from Latin, and so would not be expected to be supported by Unicode.
A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z  

Superscript capital  ᴬ  ᴮ   ᴰ  ᴱ   ᴳ  ᴴ  ᴵ  ᴶ  ᴷ  ᴸ  ᴹ  ᴺ  ᴼ  ᴾ   ᴿ  ᵀ  ᵁ  ⱽ  ᵂ  
Superscript small cap     ᶦ  ᶫ  ᶰ   ᶸ   
Superscript minuscule  ᵃ  ᵇ  ᶜ  ᵈ  ᵉ  ᶠ  ᵍ  ʰ  ⁱ  ʲ  ᵏ  ˡ  ᵐ  ⁿ  ᵒ  ᵖ   ʳ  ˢ  ᵗ  ᵘ  ᵛ  ʷ  ˣ  ʸ  ᶻ 
Overscript capital  ◌ᷛ  ◌ᷞ  ◌ᷟ  ◌ᷡ  ◌ᷢ  
Overscript minuscule  ◌ͣ  ◌ᷨ  ◌ͨ  ◌ͩ  ◌ͤ  ◌ᷫ  ◌ᷚ  ◌ͪ  ◌ͥ  ◌ᷜ  ◌ᷝ  ◌ͫ  ◌ᷠ  ◌ͦ  ◌ᷮ  ◌ͬ  ◌ᷤ  ◌ͭ  ◌ͧ  ◌ͮ  ◌ᷱ  ◌ͯ  ◌ᷦ  
Subscript minuscule  ₐ  ₑ  ₕ  ᵢ  ⱼ  ₖ  ₗ  ₘ  ₙ  ₒ  ₚ  ᵣ  ₛ  ₜ  ᵤ  ᵥ  ₓ  
Underscript minuscule  ◌᷊  ◌ᪿ 
Α  Β  Γ  Δ  Ε  Ζ  Η  Θ  Ι  Κ  Λ  Μ  Ν  Ξ  Ο  Π  Ρ  Σ  Τ  Υ  Φ  Χ  Ψ  Ω  

Superscript minuscule  ᵝ  ᵞ  ᵟ  ⁽ᵋ⁾  ᶿ  ⁽ᶥ⁾  ⁽ᶹ⁾  ᵠ  ᵡ  
Overscript minuscule  ◌ᷩ  
Subscript minuscule  ᵦ  ᵧ  ᵨ  ᵩ  ᵪ 
ɑ  æ  ç  ð  ə  ʃ  ʍ  ʔ  

Superscript  See superscript IPA letters  
Overscript  ◌ᷧ  ◌ᷔ  ◌ᷗ  ◌ᷙ  ◌ᷪ  ◌ᷯ  ◌̉  
Subscript  ₔ  
Underscript  ◌ᫀ 
(Superscript ɩ ᶅ ƫ ɷ, which are no longer IPA, are ⟨ᶥ ᶪ ᶵ ⟩.)
А  Ә  Б  В  Г  Ґ  Д  Е  Є  Ж  З  Ѕ  Ꚉ  И  І  Ї  Ј  К  Л  М  Н  О  Ө  П  Р  С  Ҫ  

Superscript                  ᵸ        
Overscript  ◌ⷶ  ◌ⷠ  ◌ⷡ  ◌ⷢ  ◌ⷣ  ◌ⷷ  ◌ꙴ  ◌ⷤ  ◌ⷥ  ◌ꙵ  ◌  ◌ꙶ  ◌ⷦ  ◌ⷧ  ◌ⷨ  ◌ⷩ  ◌ⷪ  ◌ⷫ  ◌ⷬ  ◌ⷭ  
Subscript                   
Т  У  Ү  Ұ  Ꙋ  Ф  Х  Ѡ  Ц  Ч  Џ  Ш  Щ  Ъ  Ꙑ  Ы  Ь  Ѣ  Э  Ю  Ꙗ  Ѥ  Ѧ  Ѫ  Ѭ  Ѳ  Ӏ  
Superscript           ꚜ    ꚝ     
Overscript  ◌ⷮ  ◌ꙷ  ◌ⷹ  ◌ꚞ  ◌ⷯ  ◌ꙻ  ◌ⷰ  ◌ⷱ  ◌ⷲ  ◌ⷳ  ◌ꙸ  ◌ꙹ  ◌ꙺ  ◌ⷺ  ◌ⷻ  ◌ⷼ  ◌ꚟ  ◌ⷽ  ◌ⷾ  ◌ⷿ  ◌ⷴ  
Subscript          
Many of these characters were added to Unicode 15, in the Cyrillic ExtendedD block, and published in 2022.^{[8]}
See also small caps in Unicode.
Primarily for compatibility with earlier character sets, Unicode contains a number of characters that compose super and subscripts with other symbols.^{[1]} In most fonts these render much better than attempts to construct these symbols from the above characters or by using markup.