Unicode has precomposed characters only for common fractions. ½ ¼ ¾ are in Latin-1 and have been available since the 1980s; the rest are in the Number Forms block. All of them have compatibility decompositions: NFKC turns ½ into the three characters 1⁄2, which matters for search and for databases that normalize input.
For any other fraction, write the digits around ⁄ U+2044 FRACTION SLASH — for example 17⁄20. Fonts that support the OpenType frac feature render that as a proper fraction. Without font support, superscript and subscript digits give a similar look: ¹⁷⁄₂₀.
Click any symbol to copy it. Names link to the full character page with every encoding.