Paper Weights & Sizes Explained
Paper has an endless list of uses. Whether it’s a matte paper used for drawing or glossy paper for a leaflet, each style of paper has a host of different weights, measurements, standards and more that can be hard to wrap your head around.
This guide explains the differences between paper types so that you can ensure you’re choosing the right paper for your intended use.
Paper sizes – explained
As standard, there are two accepted paper sizing systems – the North American system and the international system[i]. But there are a few lesser-known standards such as ANSI which are used in certain circles but are nowhere near as popular.
Sometimes you might come across a paper size you aren’t familiar with, or you may need to choose the right sized paper for poster printing or artwork. Below, we discuss the differences in standards and show you the size conversions for the most common paper standards.
IS0 216 – International Standard
The international standard is known as the ISO 216 standard (previously known as DIN 476). This system was first imagined in 1786 by German scientist Georg Christoph Lichtenberg[ii], and some of the ISO formats we know today (A2, A3, B4 & B5) were developed later on in France. Today, the most common ISO standard that we use is A4. The measurements for the standard are based on the following: -
- Length/Width = 1.4142
- The length and width of each size must be rounded up to the closest mm
- A0 sizes have an area of 1 square metre[iii]
The easiest way to envision the paper's size in your mind is that as the number of the format goes up, the sizing goes down. It is also always half the size of the number standard above it, for example. A2 is half the size of A3, and A2 is half the size of A1.
IS0 216 - A Series
The following table shows conversions for A standard paper.
Format Number |
Inches |
Centimetres |
Millimetres |
A0 |
33.1 x 46.8 in |
84.1 x 118.9 cm |
841 x 1189 mm |
A1 |
23.4 x 33.1 in |
59.4 x 84.1 cm |
594 x 841 mm |
A2 |
16.5 x 23.4 in |
42.0 x 59.4 cm |
420 x 594 mm |
A3 |
11.7 x 16.5 in |
29.7 x 42.0 cm |
297 x 420 mm |
A4 |
8.3 x 11.7 in |
21.0 x 29.7 cm |
210 x 297 mm |
A5 |
5.8 x 8.3 in |
14.8 x 21.0 cm |
148 x 210 mm |
A6 |
4.1 x 5.8 in |
10.5 x 14.8 cm |
105 x 148 mm |
A7 |
2.9 x 4.1 in |
7.4 x 10.5 cm |
74 x 105 mm |
A8 |
2.0 x 2.9 in |
5.2 x 7.4 cm |
52 x 74 mm |
A9 |
1.5 x 2.0 in |
3.7 x 5.2 cm |
37 x 52 mm |
A10 |
1.0 x 1.5 in |
2.6 x 3.7 cm |
26 x 37 mm |
ISO 216 – B Series
The following table shows conversions for B standard paper[iv].
Format Number |
Inches |
Centimetres |
Millimetres |
B0 |
39.4 × 55.7 in |
100.0 x 141.4 cm |
1000 × 1414 mm |
B1 |
27.8 × 39.4 in |
70.7 x 100.0 cm |
707 × 1000 mm |
B2 |
19.7 × 27.8 in |
50.0 x 70.7 cm |
500 × 707 mm |
B3 |
13.9 × 19.7 in |
35.3 x 50.0 cm |
353 × 500 mm |
B4 |
9.8 × 13.9 in |
25.0 x 35.3 cm |
250 × 353 mm |
B5 |
6.9 × 9.8 in |
17.6 x 25.0 cm |
176 × 250 mm |
B6 |
4.9 × 6.9 in |
12.5 x 17.6 cm |
125 × 176 mm |
B7 |
3.5 × 4.9 in |
8.8 x 12.5 cm |
88 × 125 mm |
B8 |
2.4 × 3.5 in |
6.2 x 8.8 cm |
62 × 88 mm |
B9 |
1.7 × 2.4 in |
4.4 x 6.2 cm |
44 × 62 mm |
B10 |
1.2 × 1.7 in |
3.1 x 4.4 cm |
31 × 44 mm |
North America Standards
This system is used primarily in the United States, the Philippines and Canada. The most common sizes of this standard are Tabloid/Ledger, Letter and Legal. Not much is known about how these standards came about, but they are used to describe both digital and physical formats.
Format |
Size in Inches |
Size in Millimetres |
Junior Legal |
8 x 5 |
203 x 127 |
Letter |
8.5 x 11 |
216 x 279 |
Legal |
8.5 x 14 |
216 x 356 |
Tabloid (Ledger) |
11 x 17 |
279 x 432 |
The names here are very self-descriptive, and the most widely used format is the Letter format.
ANSI
The American National Standards Institute adopted ANSI paper sizes in 1995. This standard is based on the traditional North American Letter paper size, but it isn’t widely used.
Size |
Millimetres |
Inches |
Closest ISO |
A |
216 x 279 mm |
8.5 x 11.0 in |
A4 |
B |
279 x 432 mm |
11.0 x 17.0 in |
A3 |
C |
432 x 559 mm |
17.0 x 22.0 in |
A2 |
D |
559 x 864 mm |
22.0 x 34.0 in |
A1 |
E |
864 x 1118 mm |
34.0 x 44.0 in |
A0 |
Paper weight – explained
Paper weight is usually weighed in GSM, which means Grams per Square Metre[v]. The heavier the paper stock, the higher the GSM will be. Below we will break down common GSM’s and the general use for these weights of paper.
Paper weights
35 – 55gsm – this is the standard paper weight used for newspapers. Anything below this is not useful for printing on.
70 – 100 gsm – this is the weight of standard office paper, magazines and book pages. The higher the gsm, the higher the paper quality.
100 – 120 gsm – the weight of premium stationery that is used to make envelopes and letterheaded paper.
130 – 150 gsm – this is a more durable weight, so is used for posters, flyers, leaflets and newsletters
Board weight
Paper that weighs above 170 gsm is known as board[v]. When we go above this weight, we can apply a second measure of weight in microns (1 micron = 1/1000 of a millimetre).
200 – 300gsm – premium quality brochure covers and flyers
320 – 350gsm – the standard weight of business cards and presentation folders
400gsm – invitations, good quality business cards
As this number goes up, so does the quality and durability of the board. This generally tops out at 700gsm.
Board that is different micron thicknesses can be measured as the same in GSM – so there are many variations to take into account Here is a table detailing the approximate micron thickness of different board weights.
GSM |
Micron |
200gsm |
150 - 220mics |
250gsm |
190 - 285mics |
300gsm |
237 - 342mics |
350gsm |
284 - 395mics |
400gsm |
315 - 460mics |
Why does the weight of paper matter?
Understanding the weight of paper is important when it comes to printing and designing marketing materials and is also important for artists to be aware of.
Different paper thicknesses can completely change the impact of a print. When choosing a paper or board thickness, you should take into account: -
- What is the paper for?
- Where will it be displayed?
- How durable does it need to be?
- How long does it need to last?
The paper you choose depends on what you’re intending on using it for.
For example, if you are painting, you’ll generally choose a matte paper with a thicker GSM in a size that suits your project. If you’re printing an advertising poster, you’d choose a larger but thinner piece of paper with a glossy finish.
References
Paper Sizes, 2021. International Paper Sizes & Formats. [Online] Available at: https://www.papersizes.org/[Accessed 2021 January 2021].
PaperSizes, n.d. All B Sizes. [Online] Available at: https://papersizes.io/b/ [Accessed January 2021].
Peppermint Print, 2014. Paper Weights and Thicknesses Explained. [Online] Available at: https://www.peppermintprint.co.uk/blog/paper-weights-thicknesses-explained/ [Accessed January 2021].
Printing, D., 2021. Paper Weight Guide. [Online] Available at: https://www.digitalprinting.co.uk/support/paper-weight-guide/ [Accessed January 2021].
Swift Publisher, n.d. Paper Sizes and Formats Explained: The Difference Between A4 and Letter. [Online] Available at: https://www.swiftpublisher.com/useful-articles/paper-sizes-and-formats-explained[Accessed January 2021].
Wikipedia, n.d. ISO 216. [Online] Available at: https://en.wikipedia.org/wiki/ISO_216#:~:text=The%20oldest%20known%20mention%20of,B5%20were%20developed%20in%20France. [Accessed January 2021].
Sources
[i] https://www.swiftpublisher.com/useful-articles/paper-sizes-and-formats-explained
[ii] https://en.wikipedia.org/wiki/ISO_216#:~:text=The%20oldest%20known%20mention%20of,B5%20were%20developed%20in%20France
[iii] https://www.papersizes.org/
[iv] https://papersizes.io/b/
[v] https://www.peppermintprint.co.uk/blog/paper-weights-thicknesses-explained/