How To Measure Font Size On Paper

Measurement unit of measurement used in typography

Point
A ruler showing point scale (on the lesser) and inch scale (on the top)
General information
Unit of measurement system	typographic unit of measurement
Unit of	length
Conversions
1 bespeak in ...	... is equal to ...

typographic units	1 / 12 picas
imperial/US 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 bespeak has varied throughout press'southward history. Since the 18th century, the size of a betoken has been between 0.18 and 0.4 millimeters. Post-obit the advent of desktop publishing in the 1980s and 1990s, digital press has largely supplanted the letterpress printing and has established the DTP indicate (DeskTop Publishing bespeak) as the de facto standard. The DTP point is defined as 1⁄72 of an international inch ( $ane / 72 \times 25.4 mm \approx 0.353 mm$ ) and, every bit with earlier American point sizes, is considered to be i⁄12 of a pica.

In metal type, the point size of the font describes the height of the metallic torso on which the typeface'due south characters were cast. In digital blazon, letters of a font are designed around an imaginary space chosen an em square. When a betoken size of a font is specified, the font is scaled and so that its em square has a side length of that item length in points. Although the letters of a font normally fit within the font's em foursquare, there is not necessarily any size relationship between the two, then the bespeak size does not necessarily stand for to any measurement of the size of the messages on the printed page.^[1] ^[2]

History [edit]

The point was first established past the Milanese typographer, Francesco Torniella da Novara (c. 1490 – 1589) in his 1517 alphabet, L'Alfabeto. The construction of the alphabet is the first based on logical measurement called "Punto," which corresponds to the ninth part of the height of the letters or the thickness of the principal stroke.^[3] ^[4]

Notations [edit]

A measurement in points can be represented in 3 unlike means. For instance, 14 points (1 pica plus ii points) can be written:

1P⁄2p (12 points would be only " 1P⁄ ")—traditional style
1p2 (12 points would be only "1p")—format for desktop
14pt (12 points would be "12pt" or "1pc" since information technology is the aforementioned equally i pica)—format used past Cascading Style Sheets defined by the World Wide Web Consortium.^[five]

Varying standards [edit]

Various point definitions
Proper name	Year	mm	inch
≈ 0.350 mm
Fournier^[6]	1737	≈ 0.345	0.0135
American	1886	≈ 0.3515	= 0.013837
Japanese^[7]	1962	= 0.3514	≈ 0.013835
TeX`pt`	1982	= 0. 351459 80	≈ 0.013837	= 1⁄72.27
PostScript, CSS`pt`, TeX`bp`	1984	= 0.352seven	= 0.0138	= 1⁄72
≈ 0.375 mm
Didot	1783	≈ 0.375972	≈ 0.0148
Berthold	1878	≈ 0.376	≈ 0.014801
DIN bodily,^[8] TeX`dd`	1964	= 0.376065	≈ 0.014806
DIN nominal,^[8] TeX`nd`	1984	= 0.375	≈ 0.014764
Other
Truchet	1694	≈ 0.188	≈ 0.007401
Fifty'Imprimerie Nationale nominal	1810	= 0.400	≈ 0.015748
L'Imprimerie Nationale actual	1810	= 0.398 77 mm	≈ 0.0157
DIN,^[9] Japanese, CSS`q`	1999	= 0.250	≈ 0.009842

At that place have been many definitions of a "indicate" since the appearance of typography. Traditional continental European points at nigh 0.375 mm are ordinarily a chip larger than English points at around 0.350 mm.

French points [edit]

The Truchet point, the first modern typographic indicate, was 1⁄144 of a French inch or ane⁄1728 of the royal foot. It was invented past the French chaplain Sébastien Truchet. During the metrication of France amid its revolution, a 1799 law declared the meter to exist exactly 443.296 French lines long. This established a length to the royal human foot of 9000 ⁄ 27706 m or about 325 mm, which made the Truchet point equal to 15625 ⁄ 83118 mm or about 0.187986 mm. Information technology has also been cited as exactly 0.188 mm.

The Fournier indicate was established by Pierre Simon Fournier in 1737.^[ten] ^[11] ^[12] ^: lx–66 The system of Fournier was based on a dissimilar French human foot of c. 298 mm. With the usual convention that i foot equals 12 inches, ane inch (pouce) was divided into 12 lines (lignes) and one line was further divided into six typographic points (points typographiques). 1 point Fournier = 0.0135 English inches.

The Fournier scale: two inches in total, divided into four one-half-inches, the medium intervals are one line (

1⁄12 inch), and the smallest intervals are

1⁄36 inch; no intervals for the indicate is given, though

Fournier printed a reference scale of 144 points over two inches; yet, information technology was too rough to accurately measure a single point.^[11]

The Didot point, established by François-Ambroise Didot in 1783,^[thirteen] was an endeavour to improve the Fournier system. He did not change the subdivisions (one inch = 12 subdivisions = 72 points), just divers it strictly in terms of the regal foot, a legal length measure in French republic: the Didot betoken is exactly 1⁄864 of a French foot or 1⁄72 of a French inch, that is (by 1799) 15625 ⁄ 41559 mm or most 0.375972 mm. Accordingly, one Didot point is exactly two Truchet points.

Withal, 12 Fournier points turned out to exist xi Didot points,^[eleven] ^{: 142–145} giving a Fournier point of almost 0.345 mm; subsequently sources^[12] ^: 60–61 country it as being 0.34875 mm. In Belgium the Fournier system was used until the 1970s and later. It was chosen the "mediaan"-system. To avert confusion between the new and the old sizes, Didot as well rejected the traditional names, thus parisienne became corps 5, nonpareille became corps vi, and so on.^[11] ^: 143 The Didot system prevailed because the French government demanded printing in Didot measurements.^[14] ^{[ better source needed ]}

The Fournier indicate did not achieve lasting popularity despite existence revived by the Monotype Corporation in 1927.^{[ commendation needed ]} It was still a standard in Kingdom of belgium, in parts of Austria, and in Northern France at the beginning of the 20th century.^[12] ^: 66

Other European points [edit]

Approximations were subsequently employed, largely owing to the Didot signal's unwieldy conversion to metric units (the divisor of its conversion ratio has the prime factorization of 3× 7 × 1979 ).

In 1878, Hermann Berthold divers 798 points equally being equal to 30 cm, or 2660 points equalling ane meter: that gives effectually 0.376 mm to the point.^[15] ^[16] ^[17] ^[eighteen] A more precise number, 0.376065 mm, sometimes is given;^[xvi] this is used by TeX as the dd unit. This has go the standard in Germany^[8] and Central and Eastern Europe.^[nineteen] This size is still mentioned in the technical regulations of the Eurasian Economic Marriage.^[20]

Metric points [edit]

pdfTEX, but not evidently TeX or LaTeX, also supports a new Didot bespeak (nd) at 3⁄8 mm or 0.375 mm and refers to a not further specified 1978 redefinition for it.

The French National Print Office adopted a point of ii⁄5 mm or 0.400 mm in about 1810 and continues to use this measurement today (though "recalibrated" to 0.39877 mm).^[21] ^[22] ^[23]

Japanese^[24] and German language^[ix] ^[16] ^[eighteen] standardization bodies instead opted for a metric typographic base mensurate of exactly 1⁄iv mm or 0.250 mm, which is sometimes referred to as the quart in Japan. The symbol Q is used in Japanese after the initial letter of the alphabet of quarter millimeter. Due to demand past Japanese typesetters, CSS adopted Q in 2015.^[25] ^[26]

ISO 128 specifies preferred line thicknesses for technical drawings and ISO 9175 specifies respective pens. The steps between nominal sizes are based on a cistron of √two ≈ ane.414 in guild to lucifer ISO 216 newspaper sizes. Since the set up of sizes includes thicknesses of 0.1 mm, 0.five mm, ane mm and 2 mm, there is also one of 0.35 mm which is nigh exactly 1 pica betoken. In other words, 2^−ane.5 mm = 1⁄√8 mm approximates an English typographic bespeak rather well.

American points [edit]

The basic unit of measurements in American typography was the pica,^[12] ^[27] ^[28] commonly approximated every bit one sixth of an inch, just the exact size was non standardized, and various blazon foundries had been using their own.^[12]

After the American war of Independence Benjamin Franklin was sent equally commissioner (Ambassador) for the U.s.a. to French republic (Dec 1776 to 1785).^[29] While living at that place he had intimate contact with the Fournier family, including the male parent and Pierre Simon Fournier. Franklin wanted to teach his grandson Benjamin Franklin Bache about printing and typefounding, and arranged for him to be trained past Francois Ambroise Didot. Franklin and then imported French typefounding equipment to Philadelphia to help Bache set up a type-foundry. Around 1790, Bache published a specimen canvas with some Fournier types.^[thirty] ^[31] After the decease of Franklin, the matrices and the Fournier mould were acquired past Binny and Ronaldson, the first permanent blazon-foundry in America. Successive mergers and acquisitions in 1833, 1860 and 1897 saw the company somewhen go known as MacKellar, Smith & Hashemite kingdom of jordan. The Fournier cicero mould was used by them to cast pica-sized type.

Nelson Hawks proposed, like Fournier, to split up one American inch exactly into half dozen picas, and one pica into 12 points. Nonetheless, this saw an opposition because the majority of foundries had been using picas less than 1 sixth of an inch. So in 1886, later on some exam of various picas, the Blazon Founders Association of the United States canonical the pica of the 50. Johnson & Co. foundry of Philadelphia (hence the Johnson pica) as the most established.^[27] The company went on to become MacKellar, Smiths, & Jordan Co. and was finally acquired by the Type Founders Association. The official definition of 1 pica is 0.166044 inches (4.2175 mm), and one point is 0.013837 inches (0.3515 mm). That means six picas or 72 points constitute 0.99624 standard inches. A less precise definition is i pica equals 0.166 inches (4.2 mm), and one point 0.01383 inches (0.351 mm).^[27] ^[32] It was also noticed that 83 picas is well-nigh equal to 35 cm, then the Type Founders Association also suggested using a 35 cm metal rod for measurements, merely this was non accepted by every foundry.^[27]

This has become known as the American point system.^[27] ^[32] The British foundries accepted this in 1898.

In modern times this size of the indicate has been approximated as exactly ane⁄72.27 (0.013837 000138 37 ) of the inch^[33] by Donald Knuth for the default unit of his TeX figurer typesetting organisation and is thus sometimes known as the TeX point , which is 0. 351459 80 mm.

Old English Points [edit]

Although the English Monotype manuals used i pica = .1660 inch, the manuals used on the European continent use another definition: there one pica = .1667 inch, the Old English Pica.

Every bit a event all the tables of measurements in the German, Dutch, French, Polish and all other manuals elsewhere on the European continent for the limerick caster and the super-pulley are unlike in quite some details.

The Monotype wedges used at the European continent are marked with an extra East backside the set-size: for example: v-12E, 1331-15E etc. When working with the Due east-wedges in the larger sizes the differences volition increment even more.^[34]

Desktop publishing point [edit]

The desktop publishing point (DTP indicate) or PostScript point is defined as 1⁄72 or 0.0138 of the international inch, making it equivalent to 25.iv⁄72 mm = 0.352vii mm. Twelve points make up a pica, and half-dozen picas make an inch.

This specification was developed past John Warnock and Charles Geschke when they created Adobe PostScript. It was adopted by Apple Computer every bit the standard for the brandish resolution of the original Macintosh desktop computer and the print resolution for the LaserWriter printer.^[35] ^[36]

In 1996, it was adopted by W3C for Cascading Stylesheets (CSS) where it was later related at a fixed 3:4 ratio to the pixel due to a general (merely wrong) supposition of 96 pixel-per-inch screens.

Apple point [edit]

Since the advent of high-density "Retina" screens with a much college resolution than the original 72 dots per inch, Apple tree's programming environment Xcode sizes GUI elements in points that are scaled automatically to a whole number of physical pixels in order to accommodate for screen size, pixel density and typical viewing distance. This Cocoa point is equivalent to the pixel px unit in CSS, the device pixel dp on Android and the effective pixel epx or ep in Windows UWP.

Font sizes [edit]

In lead typecasting, nearly font sizes unremarkably used in printing have conventional names that differ by country, language and the type of points used.

Desktop publishing software and give-and-take processors intended for office and personal apply frequently accept a list of suggested font sizes in their user interface, but they are non named and usually an arbitrary value can be entered manually. Microsoft Discussion, for instance, suggests every fifty-fifty size betwixt eight and 28 points and, additionally, ix, xi, 36, 48 and 72 points, i.e. the larger sizes equal 3, 4 and 6 picas. While well-nigh software nowadays defaults to DTP points, many let other units, especially code-based systems similar TeX and CSS.

References [edit]

^ Phinney, Thomas (16 August 2012). "Point Size and the Em Foursquare: Not What People Recollect". Phinney on Fonts . Retrieved 26 Feb 2018.
^ "15.7. Font size: the 'font-size' property", Cascading Fashion Sheets Level 2 Revision two (CSS 2.2) Specification, World wide web Consortium, 12 April 2016, retrieved 26 February 2018
^ Mardersteig, Giovanni (1971). The alphabet of Francesco Torniello da Novara [1517]: Followed by a comparison with the alphabet of Fra Luca Pacioli. Officina Bodoni.
^ Healey, Robin (2011). Italian Literature Before 1900 in English Translation: An Annotated Bibliography, 1929-2008. Academy of Toronto Press. ISBN9781442642690.
^ "four.iii.ii. Lengths", Cascading Style Sheets, level two CSS2 Specification, World wide web Consortium, 12 Apr 2016, retrieved 26 Feb 2018
^ Diverse sources give different sizes, namely: ≈ 0.0135 in, ≈ 0.0137 in, ≈ 0.345 mm, (exactly) 0.34875 mm, ≈ 0.349 mm, ≈ 0.35 mm.
^ JIS Z 8305. 活字の基準寸法. Dimensions of Press Types.
^ ^a ^b ^c DIN 16507-1:1998 and its predecessors, at to the lowest degree since 1964, for lead typecasting defined 2660 points to measure 1000.333 mm at 20 °C, but for public advice information technology later introduced a rounder value.
^ ^a ^b DIN 16507-2 (1984, 1999) does not specify a custom unit for electronic typography, only measures using a module.
^ Fournier, Pierre Simon (1764). Manuel typographique. pp. 125–138.
^ ^a ^b ^c ^d De Vinne, Theodore Low (1900). The practice of typography. Vol. 1. New York: Century Co. pp. 133–145.
^ ^a ^b ^c ^d ^eastward Legros, Lucien Alphonse; Grant, John Cameron (1916). Typographical Press-Surfaces. London and New York: Longmann, Green, and Co. pp. 57–60. ISBN9785872323303.
^ Baines, Phil; Haslam, Andrew (2005). Type & Typography. Laurence King Publishing. p. 93. ISBN978-one-85669-437-vii.
^ Fifty. Ronner, Van leerling tot Zetter, 1913, N.Five.De nieuwe Tijd, Amsterdam, pag 30.
^ Smalian, Hermann (1899). "Blazon Systems of To-day". The British Printer. XII (68): 130–131. They commissioned for this purpose the well-known Berlin brass dominion manufacturer, H. Berthold, who supplies brass rules not only to almost of the High german foundries simply also to many foreign houses, and he, in conjunction with Prof. W. Fürster, the primary director of the Berlin Observatory, agreed that 2660 typographical points of the Didot system should correspond to 1 metre. Accordingly the Standard Gauge Committee in Berlin in 1879 arranged a standard measure of 30 centimetres = 133 nonpareil or 798 typographical points, and gave a re-create to all the German foundries, and since that fourth dimension disputes well-nigh the Didot depth were unknown in Germany.
^ ^a ^b ^c Brekle, Herbert E. (1994). "Typographie". Schrift und Schriftlichkeit / Writing and its Use. Walter de Gruyter. p. 210ff. ISBN978-3-xi-020323-3.
^ Funke, Fritz (1998). Buchkunde. De Gruyter. p. 194. ISBN978-3-11-094929-2.
^ ^a ^b Blana, Hubert (1999). Die Herstellung: Ein Handbuch für dice Gestaltung, Technik und Kalkulation von Buch, Zeitschrift und Zeitung. Walter de Gruyter. p. 101. ISBN978-3-xi-096787-6.
^ "§1.iii". GOST 3489.i-71. Printing types (Russian and Roman graphic bases). Group organisation. Indexing. Base line. Characters per 4 picas ГОСТ 3489.1-71. Шрифты типографские (на русской и латинской графических основах). Группировка. Индексация. Линия шрифта. Емкость (in Russian). Кегль измеряется в типографских пунктах. Типографский пункт равен 0,376 мм.
^ (in Russian) Статья viii. Пункт eleven. // ТР ТС 007/2011. Требования безопасности издательской (книжной и журнальной) продукции, школьно-письменных принадлежностей.
^ Mosley, James (1997). "French academicians and modern typography: designing new types in the 1690s". Typography Papers (2): 5–29. The point in current use at the Imprimerie Nationale measures 0.39877 mm. This appears to be the event of a 'recalibration', for which no date can be given, of the signal of 0.4 mm.
^ Bulletin du bibliophile. 2002. p. 73. ISBN9782765407768. These latter figures give the size in the 'points millimétriques' of almost 0.4 mm that are said to have been introduced at the Imprimerie impériale past Firmin Didot and which are the footing for the 'betoken IN' used today at the Imprimerie nationale.
^ "Blazon bodies compared". Typefoundry. 30 April 2008.
^ JIS Ten 4052:2000, JIS Z 8125:2004
^ "CSS Values and Units Module Level three". Www Consortium. 29 September 2016.
^ "CSS Values and Units Module Level 3". Www Consortium. 11 June 2015.
^ ^a ^b ^c ^d ^{due east} De Vinne, Theodore Depression (1900). The practice of typography. Vol. 1. New York: Century Co. pp. 145–156.
^ Hyde, Grant Milnor (1920). Newspaper Editing: A Manual for Editors, Copyreaders, and Students of Paper Desk Work. New York and London: D. Appleton and Visitor. pp. 226–227.
^ Benjamin Franklin papers, Kislak Middle for Special Collections, Rare Books and Manuscripts, University of Pennsylvania
^ Updike, I, p. 257, Two pp. 152-3
^ Allen Huet, Fournier the compleat typographer, 1972, London, Frederik Muller Ltd, folio 3, 4, 62, 63
^ ^a ^b "The American Signal System". American Printer and Lithographer. 11: 89. 1890.
^ Knuth, Donald East. (1990). The TeXbook (17th revised ed.). Addison-Wesley. p. 58.
^ Rich Hopkins, Origin of the American Betoken system for Printers; Type Measurement, Jill & Dale individual Press, Terra Alta, West Virginia, 1976, 2e impression 1989
^ Tucker, H. A. (1988). "Desktop Publishing". In Ruiter, Maurice 1000. de (ed.). Advances in Calculator Graphics III. Springer. p. 296. ISBN3-540-18788-X.
^ Spring, Michael B. (1991). Electronic printing and publishing: the document processing revolution. CRC Press. p. 46. ISBN0-8247-8544-4.