Paper Size Guide In 2021!

Have you ever wondered why we have paper sizes? 

You need to buy printing paper for your office or your home, and you have no idea what A4 or any of the multiple sizes these papers are available in. If you need a short course on paper sizes, read on. 

The Standardization Of Paper Sizes

You see papers in many sizes but still uniform in various aspects, that's because the printing industry decides and dictates the size of paper for decades. These paper sizes then help you design the sizes of envelopes, frames, binders, and even printer trays. The paper sizes need to be uniform in order to have more universally accepted sizes of other related objects. 

Thankfully there are standard paper sizes that you can find in any part of the world. The ISO standards of paper sizes are used in most parts of the world and North America uses a slightly different system known as ANSI or American National Standards Institute.

Let's look at the ISO standards for paper first.

A Size

These paper sizes are governed by the International Standardization Of Organization or ISO 216. First set in the early 1900s, the most commonly known ISO paper size is the A4 paper size.

The ISO standards are ruled by a basic aspect ratio for each format that is the square root of 2. (1:4142). When printing by a different format under ISO standards, the uniform aspect ratio allows easy enlargement or reduction of paper size. All the paper sizes are named with the letter A followed by a number, wherein the larger the number, the smaller the size of paper. If you continue to fold the A0 paper size in the middle, along its shortest sides, you get two sheets of A1 size and so on. 

B Size

The B sizes were introduced to accommodate larger sizes of paper usually consisting of posters. The same rule of B followed by a number of makes the series. The  B sizes are based on the geometrical mean of two successive A series sheets. So the B1 is between A0 and A1 in size, and B3  is between A2 and A3 in size. 

The C series of the paper sizes are almost exclusively used for envelopes only. These sizes also correspond to their counterparts in the A-series. So an A4 paper will fit into an envelope of size C4. 

The American Sizes

The US and Canada follow the North American sizes. These paper sizes are traditional in format but do not follow any strict aspect ratio. The most common sizes in North American sizes are letter legal and tabloid. These sizes are the most commonly used sizes of paper for printing and official work though with an arbitrary rule for deciding the sizes. The A4 Size corresponds most closely to letter size, but other sizes do not match closely within the two sizes standards.

Since there isn't a set aspect ratio for paper sizes, the increase and decrease in the size of the paper to fit the ANSI paper sizes can be difficult. 

Finally, knowing the standard for paper sizes can help you recognize and improvise according to your needs. Take your time to explore ThunderBolt papers who bring you printing papers in North American sizes so that you don't have to worry about finding the right size. Whether it is an official document or an architectural diagram, you will know exactly what size to look for. Tell us which printing paper sizes do you use often?