Superior and Inferior Figures
Superior and inferior figures are numerals that are smaller versions of full-size lining figures. These diminutive numerals most commonly appear in diagonal fractions, but they are also used for footnotes and endnotes, chemical and mathematical notations, and occasionally for indicating the cents in prices in display settings.
Proper, true-drawn superiors and inferiors are designed to be visually compatible with the full-size figures in terms of weight and proportions. In other words, they are not simply reduced lining figures, which would be both too light and too narrow. The superior figures in a typeface may align at and/or slightly above the cap height, while inferiors may sit on and/or below the baseline. Some typefaces offer all four alignments. The specific usage will determine which alignment is appropriate. For instance, “high” superiors are ideal for footnotes and math formulas, whereas the cap-aligned version is the standard for numerators. Baseline-aligned inferiors are used for denominators, and those that sit below the baseline for some chemical formulas.
Superior and inferior figures are sometimes referred to as superscript and subscript glyphs. In some instances these terms are indeed interchangeable, but not always. Superscript or subscript can also be a software command to raise or lower a character or symbol. The command may automatically generate a superior or inferior figure, by reducing (usually to about 60%) the full-size version. In this scenario, the inserted figure will not harmonize with the surrounding type in form or color, creating a visual distraction.
An increasing number of OpenType® fonts include a complete set of true-drawn superior and inferiors, thanks to the format’s capacity to accommodate thousands of characters. Note that older font formats (Type 1 and TrueType) only had “room” for the 1, 2 and 3 superior figures, necessitating the use of automatically generated reduced figures for the others. If your project requires superiors and inferiors, select typefaces that contain a full set of the true-drawn variety, in order to achieve the most professional typographic results.
- Editor’s Note:Ilene Strizver, founder of The Type Studio, is a typographic consultant, designer and writer specializing in all aspects of typographic communication. She conducts Gourmet Typography workshops internationally. Read more about typography in her latest literary effort, Type Rules! The designer's guide to professional typography, 4th edition, published by Wiley & Sons, Inc. This article was commissioned and approved by Monotype Imaging Inc.