Point (typography)

Point
A ruler showing point scale (on the bottom) and inch scale (on the top)
General information
Unit systemtypographic unit
Unit oflength
Conversions
1 point in ...... is equal to ...
   typographic units   1/12 picas
   imperial/U.S. units   1/72 in
   metric (SI) units   0.3528 mm

In typography, the point is the smallest unit of measure. It is used for measuring font size, leading, and other items on a printed page. The size of the point has varied throughout printing's history. Since the 18th century, the size of a point has been between 0.18 and 0.4 millimeters. Following the advent of desktop publishing in the 1980s and 1990s, digital printing has largely supplanted the letterpress printing and has established the desktop publishing (DTP) point as the de facto standard. The DTP point is defined as 172 of an inch (0.3528 mm) and, as with earlier American point sizes, is considered to be 112 of a pica.

In metal type, the point size of the font describes the height of the metal body on which the typeface's characters were cast. In digital type, letters of a font are designed around an imaginary space called an em square. When a point size of a font is specified, the font is scaled so that its em square has a side length of that particular length in points. Although the letters of a font usually fit within the font's em square, there is not necessarily any size relationship between the two, so the point size does not necessarily correspond to any measurement of the size of the letters on the printed page.[1][2]

  1. ^ Phinney, Thomas (16 August 2012). "Point Size and the Em Square: Not What People Think". Phinney on Fonts. Retrieved 26 February 2018.
  2. ^ "15.7. Font size: the 'font-size' property", Cascading Style Sheets Level 2 Revision 2 (CSS 2.2) Specification, World Wide Web Consortium, 12 April 2016, retrieved 26 February 2018