A4, B5, A5—these are some of the most commonly used paper sizes in the world, but to North Americans they may sound more like bingo calls than paper sizes. In the US, Canada, and Mexico, the standard paper size is Letter size: 8.5" × 11". Outside of North America, however, Letter size is rarely used.1 Instead, other countries use a system of paper sizes that may seem confusing at first but is actually quite simple and logical once you understand the methodology behind it.
Read on or watch the video below to learn more about how international paper sizes work, how different sizes compare to Letter size, and which paper sizes work best for different applications.
Most countries outside of North America use paper that fall into one of two sizes: the A sizes and the B sizes. There are also C sizes, but it is mainly used for creating envelopes manufactured to fit A size papers, so we won't discuss it here. A sizes are more commonly used than B sizes, so let's begin with them.

A sizes start with the largest size, A0, which is 84.1 cm × 118.9 cm, or about 33.1" × 46.8". Each smaller size is obtained by taking the next largest size and cutting it in half, creating a size with the same proportions and half the surface area.

Within the A sizes, A4 size is the closest to North American Letter size and is the standard paper size in countries that use A sizes. At approximately 8.3" × 11.7" (21 cm × 29.7 cm), it is slightly longer and narrower than Letter size.

Unfortunately, B sizes get a bit more complicated. Unlike A sizes, which are the same everywhere, the exact dimensions of B sizes are defined differently in Japan than they are in the rest of the world.

If all of that is too complicated to remember, just note that B sizes can vary slightly from one product line to another, so be sure to check the specific product dimensions for any B size paper or notebook if it needs to be exactly the right size.
Below, we have listed the most commonly used paper sizes for loose leaf paper, notebooks, and notepads from largest to smallest. For B sizes, we list the Japanese sizes since they are much more commonly used among the products we carry. ISO B sizes are listed separately in a drop-down table further down. As explained above, A sizes are the same in Japan and internationally.
Size (Large to Small) |
Width | Length | Area | Comparison to Letter Size |
---|---|---|---|---|
B4 (JIS) | 10.1 in 25.7 cm |
14.3 in 36.4 cm |
145.0 in² 935.5 cm² |
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A4 | 8.3 in 21.0 cm |
11.7 in 29.7 cm |
96.7 in² 623.7 cm² |
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Letter | 8.5 in 21.6 cm |
11.0 in 27.9 cm |
93.4 in² 602.6 cm² |
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B5 (JIS) | 7.2 in 18.2 cm |
10.1 in 25.7 cm |
72.5 in² 467.7 cm² |
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Semi B5 (JIS) | 7.0 in 17.7 cm |
9.8 in 25.0 cm |
68.6 in² 442.5 cm² |
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A5 | 5.8 in 14.8 cm |
8.3 in 21.0 cm |
48.2 in² 310.8 cm² |
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B6 (JIS) | 5.0 in 12.8 cm |
7.2 in 18.2 cm |
36.1 in² 233.0 cm² |
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A6 | 4.1 in 10.5 cm |
5.8 in 14.8 cm |
24.1 in² 155.4 cm² |
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Pocket* | 3.5 in 8.9 cm |
5.5 in 14.0 cm |
19.2 in² 124.6 cm² |
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B7 (JIS) | 3.6 in 9.1 cm |
5.0 in 12.8 cm |
18.1 in² 116.5 cm² |
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A7 | 2.9 in 7.4 cm |
4.1 in 10.5 cm |
12.0 in² 77.7 cm² |
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*Pocket size is not standardized, but it is a commonly used size that is typically around 3.5" × 5.5".
There are a few considerations to keep in mind when choosing a paper size. Larger paper sizes offer more space for writing and drawing, but they also take up more space on your desk, in your bag, or on your shelf. What size is right for you will depend on how and where you intend to use it. Here are some recommended paper sizes and products we think are best for a variety of applications.
Recommended Sizes: A4, Letter, B5 / Semi B5
Students need plenty of space for taking notes, and since they often are carrying a backpack with them anyway, carrying a larger notebook or binder shouldn't be a problem. Assignments that need to be turned in will most likely need to be done on standard Letter size paper (or A4 paper for students outside of North America).
Maruman Mnemosyne notebooks feature high-quality paper and sleek, durable covers that will protect your notes from getting creased or crumpled in your backpack. A wide range of additional sizes and paper styles are also available.
With one of these slim and colorful notebooks for each class, you can easily keep your notes organized. You'll also know which notebooks to carry for the classes you have on any one day. Plus, the dotted line rule is great for creating diagrams, graphs, and other figures in your notes.
This slim binder lets you easily change or reorganize your notes on the fly. Use it with pre-punched filler paper or make your own with a hole punch.
Recommended Sizes: A4, Letter, B5 / Semi B5, A5, B6, A6
The perfect paper size for office note-taking will depend on your desk space and how much writing you do. A copious note-taker with plenty of space will want a large notebook or notepad holder, while a simple notepad is perfect someone who just needs to jot down an occasional list or reminder.
Perfect for those with lots of notes and documents to keep track of, this holder includes an A4 notepad as well as five separate pockets for holding A4 or Letter sized papers. The holder is made from durable plastic and has an elastic band closure to keep its contents secure.
With its sleek, modern style, this notebook is at home in any office environment. Its convenient dot grid paper style makes it easy to write or draw on while being less conspicuous than a typical line or grid pattern.
This compact notepad is just right for jotting down quick notes and lists. It features a sleek white cover and subtle gray grid pattern.
The perfect journal is large enough to write out all your thoughts without feeling cramped, yet small enough to fit unobtrusively in a drawer or on a desk or nightstand. A medium-sized notebook in the A6 to A5 range is just right for this.
Featuring the classic design of a hardcover notebook with an elastic closure and back cover pocket for storing notes and memorabilia, this notebook is a perfect receptacle for your thoughts and inspirations. Filled with smooth, high-quality 90 gsm paper, it is a particularly good choice for fountain pen users.
These refillable, leatherette journals are available in a variety of fun and classic colors, letting you choose the one the best captures your personality. Each page of the journal insert features a perforated tear-off corner so that you can easily flip to the next unused page.
These slim notebooks feature Midori Diary (MD) paper, which is well-loved for its ability to provide a pleasant experience for any writing instrument, especially fountain pens. It also includes label stickers, so you can index your journals and keep track of when you start and finish them.
Recommended Sizes: Pocket, B7, A7
For taking notes on the go, a portable notebook should be small enough to carry easily in a pocket or bag. Pocket notebooks are just small enough to fit into a typical back pants pocket, while the smaller B7 and A7 sizes will fit more easily into a shirt, jacket, or front pants pocket.
This durable leather notebook is actually a cover that can hold up to three staple-bound pocket notebooks at once! You can keep a planner, a notebook, and a sketchbook all together in one convenient cover and buy refills as necessary. The surface of the leather will gain a distinctive patina with use, reflecting the unique way that you have used and carried it.
A cult classic, these high-quality, made-in-the-USA memo books feature rugged staple binding and are available in a wide range of standard and seasonal editions.
These compact, colorful notepads feature firm yet flexible cardstock covers that will protect the notepad while easily conforming to the contours of your pocket. Lines on the front cover allow for easy labeling and indexing.
Recommended Sizes: Any
A sketchbook can be as big or small as you want it to be. Sketch epic landscapes or intricate multi-panel drawings on an oversized B4 pad, quick thumbnails in a mini A7 notebook, or anything in between!
This sketch pad features lightly textured, heavyweight paper that is suitable for use with a wide range of wet and dry media. Its glue binding is sturdy but allows pages to be pulled out cleanly if desired. B4 and B6 versions are also available.
These high-quality sketchbooks feature protective hard covers and a variety of paper types to choose from, each optimized for specific applications. For general sketching with pens and dry media, we recommend the Alpha Series Sketchbook.
These fun pocket sketchbooks are available in three different paper weights: 52.3 g. for pencils and other dry media, 60 g for inks and markers, and 96.4 g for light washes and watercolors.
Recommended Sizes: B4, A4, Letter
Illustrators and comic artists need plenty of space for creating detailed drawings. Professional Japanese manga artists use B4 paper for their work, but A4 or Letter size paper also provide a good amount of drawing space.
This professional-grade, loose leaf manga paper is available plain or with scale markings to help organize layouts. It is well-suited for use with ink, markers, and screen tones.
This Strathmore pad (which is also available in white) features acid-free paper that combines the characteristics of both watercolor and drawing paper, making it the best choice for artists that use wet and dry media. The cardstock cover can be folded back when the pad is in use and the glue binding allows sheets to be removed easily.
Artists that are only familiar with white sketchbooks, this softcover Stillman & Birn mixed trio sketchbook may intrigue you! Best suited for light washes and dry media, it is filled with 46 sheets of archival quality paper—16 black, 15 beige, and 15 gray—which is perfect if you are looking to experiment with light and dark media.
- The Best Notebooks For Every Use
- The Best Journals
- The Best Sketchbooks For Every Medium
- The Best Pocket Notebooks For 2021
- Maruman Mnemosyne: A Comprehensive Guide
- Kokuyo Campus: A Comprehensive Guide
- Rhodia: A Comprehensive Guide
- Midori MD Notebooks: A Comprehensive Guide
- TRAVELER'S COMPANY TRAVELER'S notebook: A Comprehensive Guide
- Field Notes: A Comprehensive Guide
We hope that this article has helped some of you to understand international paper sizes. They can seem complicated at first, but like the metric system they are actually pretty straightforward once you understand how they work. Do you have a favorite paper size for journaling, sketching, or note-taking? Let us know in the comments section below!
Size (Large To Small) |
Width | Length | Area | Recommended Use |
---|---|---|---|---|
B4 (JIS) | 10.1 in 25.7 cm |
14.3 in 36.4 cm |
145.0 in² 935.5 cm² |
Sketchbook, Comics and Illustrations |
A4 | 8.3 in 21.0 cm |
11.7 in 29.7 cm |
96.7 in² 623.7 cm² |
School Notes, Office Notes, Sketchbook, Comics and Illustrations |
Letter | 8.5 in 21.6 cm |
11.0 in 27.9 cm |
93.4 in² 602.6 cm² |
School Notes, Office Notes, Sketchbook, Comics and Illustrations |
B5 (JIS) | 7.2 in 18.2 cm |
10.1 in 25.7 cm |
72.5 in² 467.7 cm² |
School Notes, Office Notes, Sketchbook |
Semi B5 (JIS) | 7.0 in 17.7 cm |
9.8 in 25.0 cm |
68.6 in² 442.5 cm² |
School Notes, Office Notes, Sketchbook |
A5 | 5.8 in 14.8 cm |
8.3 in 21.0 cm |
48.2 in² 310.8 cm² |
Office Notes, Journal, Sketchbook |
B6 (JIS) | 5.0 in 12.8 cm |
7.2 in 18.2 cm |
36.1 in² 233.0 cm² |
Office Notes, Journal, Sketchbook |
A6 | 4.1 in 10.5 cm |
5.8 in 14.8 cm |
24.1 in² 155.4 cm² |
Office Notes, Journal, Sketchbook |
Pocket* | 3.5 in 8.9 cm |
5.5 in 14.0 cm |
19.2 in² 124.6 cm² |
Pocket Notebook, Sketchbook |
B7 (JIS) | 3.6 in 9.1 cm |
5.0 in 12.8 cm |
18.1 in² 116.5 cm² |
Pocket Notebook, Sketchbook |
A7 | 2.9 in 7.4 cm |
4.1 in 10.5 cm |
12.0 in² 77.7 cm² |
Pocket Notebook, Sketchbook |
1) Outside of North America, Letter size is sometimes referred to as American Quarto.
2) To demonstrate this phenomenon mathematically, suppose there is a sheet of paper with a long side of length a and a short side of length b, such that a/b = √2. Cutting this sheet of paper in half results in a new sheet with a long side of length b, a short side of length a/2, and an aspect ratio of b/(a/2). It then follows that: b/(a/2) = 2/(a/b) = 2/√2 = √2