Paper is a funny thing, in that one would naturally assume there is only one way to measure it. However, like a majority of all systems of measurement, paper has many different measuring regulations. Today there are two major systems using when it comes to measuring large format paper, although lesser used versions do exist.

The International Standard, also known as ISO 216, is based off of a German way of measuring large format paper known as German DIN 476.” The international standard is based on an aspect ratio of square root of 2. It features a series of different extensions, such as Swedish, Japanese, and Colombian.

North American paper sizes, usually custom within the United States, Mexico, and Canada (Mexico has adopted the ISO 216 Standard, although the U.S. ‘letter format’ is still used throughout the nation). It was in 1995 that the American National Standards Institute created the “ANSI paper size,” which is what’s mostly used around North America currently. It is designed so that when a paper-size is cut into half, it will create two complete pieces of the next-smallest size.

North American large format paper suppliers also use what is known as the “Architectural sizes” of paper, which has been adopted by many architects (hence the name) as well as many individuals in the entertainment industry.