x-height

thumb|upright 2.0|alt=A diagram showing the line terms used in typography|class=skin-invert-image In typography, the x-height, or corpus size, is the distance between the baseline and the mean line of lowercase letters in a typeface. Typically, this is the height of the letter x in the font (the source of the term), as well as the letters v, w, and z. (Curved letters such as a, c, e, m, n, o, r, s, and u tend to exceed the x-height slightly, due to overshoot; i has a dot that tends to go above x-height.) One of the most important dimensions of a font, x-height defines how high lowercase letters without ascenders are compared to the cap height of uppercase letters. thumb|Regular and caption styles of two typefaces, PT Sans and [[EB Garamond. The caption styles both have increased x-heights to make the text clear even printed small. EB Garamond's is also very visibly bolder.|class=skin-invert-image]] thumb|French renaissance typefaces, 1592. The smaller typeface at the bottom has a proportionally higher x-height.|class=skin-invert-image Display typefaces intended to be used at large sizes, such as on signs and posters, vary in x-height. Many have high x-heights to be read clearly from a distance. This, though, is not universal: some display typefaces such as Cochin and Koch-Antiqua intended for publicity uses have low x-heights, to give them a more elegant, delicate appearance, a mannerism that was particularly common in the early twentieth century. Many sans-serif designs that are intended for display text have high x-heights, such as Helvetica or, more extremely, Impact. thumb|Extra-small x-height in handwritten (but non-cursive) sign

==Design considerations== Medium x-heights are found on fonts intended for body text, allowing more balance and contrast between upper- and lowercase letters and a brighter page. They then increase again for optical sizes of fonts designed for small print, such as captions, so that they can be clearly read printed small.