Page Sizes

Paper size standards of books have varied by country before the implementation of the ISO 216 standard that is the international standard, except in North America and part of Latin America. Paper sizes here will refer to sizes for loose papers and paper used for books. Determining the paper sizes of early printers from books is difficult because they shaved off the edges more frequently.

ISO 216 A series paper sizes with comparison to Letter and Legal.

History

Before ISO 216 Standardization

Since early books were exclusively handmade materials, page sizes varied considerably and without any stand for uniformity. During the manual paper making process, the size of the paper was governed by the size of the framed screen used to hold and mould the paper material solution. The 19th century introduced the invention of metal presses, allowed for increased strength of the press and larger pages. But variations in paper and sheet sizes persist in hand production, since paper mills measure their paper differently; measuring from the outside or inside edge of each deckle. This could result in a 1/2 inch difference in size.

Late 14th Century Italian Paper Sizes

In the last 14th century, the people of Bologna enacted a law that established standards for paper manufacturers. The four sizes, named as “Imperiale, Reale, Mezzana, and Reçute, were defined in the metric system and inscribed on marble stone and also defined, weight, quality, and prices of each format. Although almost all paper sizes has a similar ratio of 1:2, for their widths to their lengths, which would later be standardized in ISO 216, the Aldine Octavos, made by the Italian publisher Adus Manutius, were much more slender or taller than the common paper size. The Aldine Octavos were thus more portable in their five by eight or four by six, and are often regarded as the first prototype of the Mass Market Paperbacks.

British Imperial System

In 1846, the United Kingdom standardized their paper sizes with the Imperial system of paper dimensions and weights. This system, measured in inches squared instead of millimeters squared, had inconsistent aspect ratios. They also had unique names, such as "Double Crown, Elephant, Double Elephant, Demy, Double Pott and Columbier." Once the UK metricated, or adapted to the metric system, in the mid-20th century, ISO 216 paper size system was implemented, most notably replacing foolscap and quarto paper (which, despite their names, were not defined by the number of folds made on a sheet before cutting) with A4 paper. The Foolscap, however, took longer to disappear and was still used in office writing, until the mid-1980's.

Traditional French Paper Sizes

France also had its own paper size system before implementing the ISO standard system in 1967. The paper sizes followed the AFNOR, France's Standardization Association standard, that was established in 1926. The most common were the Carré, which is comparable to the ISO A2, Couronne, Raisin, and Jésus, all of which are much larger than today's common ISO A4. Like the United Kingdom, France stopped using the traditional sizes when they adopted the 216 system.

International Standardization - ISO 216

Although almost all paper was made with similar width to length ratios to 1:2, it was German physicist, Georg Christoph Lichtenberg who appears to be have proposed the standardized paper size system in a letter to Johann Beckmann, dated in October of 1786. The ratio allows for sheets of paper to be folded and cut in half, lengthwise, while still preserving the same ratio. The ISO 216 paper sizes are based on German standard DIN 476, which was published on August 18th, 1922 by Dr. Walter Postmann. The standard was accepted in other European countries before the beginning of World War II and in South American during World War II. After World War II, the standard spread internationally to other countries, individually, until 1975, when it officially became the international standard (ISO 216). Currently, the ISO 216 standard has been adopted by all countries, except in the United States, Canada, and some part of Mexico.

“The ISO 216 defines the A series of paper sizes based on the principles:

• The height divided by the width of all formats is the square root of two (1.4142).
• Format A0 has an area of one square meter.
• Format A1 is A0 cut into two equal pieces. In other words, the height of A1 is the width of A0 and the width of A1 is half the height of A0.
• All smaller A series formats are defined in the same way. If you cut format An parallel to its shorter side into two equal pieces of paper, these will have format A(n+1).
• The standardized height and width of the paper formats is a rounded number of millimeters.

For applications where the ISO A series does not provide an adequate format, the B series has been introduced to cover a wider range of paper sizes. The C series of formats has been defined for envelopes.

• The width and height of a Bn format are the geometric mean between those of the An and the next larger A(n−1) format. For instance, B1 is the geometric mean between A1 and A0, that means the same magnification factor that scales A1 to B1 also scales B1 to A0.
• Similarly, the formats of the C series are the geometric mean between the A and B series formats with the same number. For example, an (unfolded) A4 size letter fits nicely into a C4 envelope, which in turn fits as nicely into a B4 envelope. If you fold this letter once to A5 format, then it will fit nicely into a C5 envelope.
• B and C formats naturally are also square-root-of-two formats.”

ISO 217 “Paper - Untrimmed Sizes”

Larger than ISO 216’s A series sizes, Raw Format A (RA) and Supplementary Raw Format A (SRA) are the untrimmed and raw paper sizes used for commercial printing, in order to be trimmed later to A series size. RA is defined as being 105% of the A series size and SRA as 115% of the A series size.

North American Paper Sizes

The United States, Canada, and the Philippines primarily use a different system of paper sizes from ISO 216. The Dutch’s two-sheet mold, invented in the late 1600s, allowed for an average maximum stretch of 44 inches and were around 17 inches front to back. Each mold resulted in a large sheet, cut in half and then quartered, creating eight 8.5 in by 11 in pieces, also known as the size of Legal sized paper. The size of the paper was so normalized, when machines dominated the paper and print industry, the United States remained consistent with the same size, keeping the hand-made paper makers in business. Although the United States used two different sizes of paper (8 in by 10.5 for government use and 8.5 in by 11 in for every other use), then-president Ronald Reagan declared that 8.5 in by 11 in was the official standard sized paper in the 1980s. The Letter size is effectively the equivalent to ISO 216 paper size A4. In 1996, the American National Standard Institute defined the paper formats, Letter size (8.5 x 11) or ANSI A, Legal (8.5 x 14) and Ledger/Tabloid (17 x 11) or ANSI B. Similar to ISO 216 standard, but inversely, as the ANSI C and so on are twice the size of the letter before, resulting in two alternating aspect ratios.

In Arthur D. Dunn’s ‘’Notes on the Standardization of Paper Sizes,’’ he details the history of paper size standardization in Canada, as well as the advantages of regulating paper sizes.