Unicode subscripts and superscripts

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Unicode has subscripted and superscripted versions of a number of characters including a full set of arabic numerals. 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 T_EX. With the exception of using "²" and "³" for squared and cubed units it is considered inadvisable to use these characters when other methods of superscript and subscript are available.

The difference between subscript/superscript and numerator/denominator glyphs. In many popular fonts the Unicode "subscript" and "superscript" characters are actually numerator and denominator glyphs. The typeface is Myriad Pro.

Note as well that most fonts that include these characters use them for mathematical numerator and denominator glyphs, 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), but are not substitutes for properly aligned small digits. Another Unicode character, the fraction slash ⁄ is visually similar to the solidus, but when used with the ordinary digits (not the superscripts and subscripts) can indicate to a layout system that a fraction, such as 11⁄12, is preferred.

The most common superscript digits were in ISO-8859-1 at positions B9_HEX, B2_HEX and B3_HEX for digits 1, 2, and 3 respectively and have therefore been carried over into those positions in the Latin-1 range of Unicode. The rest were placed in a dedicated section of Unicode at U+xxxx2070 to U+209F. The two tables below show the characters in this range. 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 (which may not render correctly in your browser); the one on the right contains the equivalents using HTML markup for the subscript/superscript.

[edit] References

• "Superscripts and Subscripts" (PDF file)