[2025 Complete Edition] Paper Size List | Professional Explanation of A, B, and Photo Standards

We are staff at PHOTOPRI , a photo exhibition quality printing service. We support professional photographers and artists in creating their works, and we answer all of their printing-related inquiries every day.

In order to express your work in the best possible way, color and composition are of course important, but the choice of "what size paper to print on" is also a crucial factor that greatly affects the impression of the work. However, when you actually try to print,

• "Which is bigger, A4 or B5?"
• "I don't know what the best print size is for my artwork data..."
• "How big is a photo exhibition that will be impressive?"
• What is the difference between A and B sizes?

Many people face questions like these. To help resolve these concerns, this article provides a comprehensive, professional-level explanation of standard sizes for A, B, and photo paper , covering everything from dimensions to area and appropriate pixel counts. It also delves into the historical background of how the standards were created and how to choose the optimal size for your application. We'll support you in your work, starting from the size selection stage.

Useful information to know! Trivia about standard paper sizes "A" and "B"

Before looking at the size chart, let's take a look at the background of how the commonly used "A" and "B" sizes came about. This knowledge may provide hints for choosing paper when considering an international exhibition or creative activities in Japan.

A size: International standard used worldwide

The A size is an international standard established in 1922 as a Deutsche Industrie Norm (DIN) based on a proposal by German physicist Oswald. Its greatest feature is that "the aspect ratio of any size is always 1:√2 (root of two) ." This is known as the "silver ratio," and it has the highly functional property of maintaining the same ratio even when folded in half. The standard A0 size (841 x 1189 mm) is designed to have an area of approximately 1 square meter, and due to its rationality, it has now been adopted as the standard size in many countries around the world.

B size: A domestic standard born from Japanese tradition

On the other hand, B size is a uniquely Japanese standard (JIS). Its roots are said to lie in Mino washi paper, which was used as official paper during the Edo period. The standard B0 size (1030 x 1456 mm) has an area of approximately 1.5 square meters, and like A size, it has an aspect ratio of 1:√2. This size has long been familiar in Japan for many uses, such as newspaper inserts, weekly magazines, and textbooks, and is deeply ingrained in our daily lives.

[Keeper's Edition] Paper Size List (A Size, B Size, Photo Paper)

Let's take a look at the specific sizes in a table. For each size, we've compiled the size (mm), area (cm²), aspect ratio, pixel equivalent (350 ppi), and diagonal (mm). Please use this as a reference when creating high-quality print data.

*The number of pixels is calculated at a resolution of 350 ppi, which is considered a benchmark for beautiful prints. For details on data creation, please also refer to the " About Data Submissions " page.

A size list (A0 Nobi to A10)

A size is the most widely used size in the world for posters, flyers, business documents, notebooks, etc. Larger sizes, A2 and above, are especially popular for photo exhibitions and art displays.

B size list (B0 Nobi to B10)

B size is the standard widely used in Japan for books, posters, train advertisements, etc. It is slightly larger than A size, so even though both sizes are "B2" and "A2," B2 gives a more powerful impression.

Photo paper standard size list (L size to full size)

These are commonly used standards for printing photographs, such as L size and 2L size. These have their own unique dimension system that differs from A size and B size. 6-cut and 4-cut are sizes that have traditionally been used for photography contests and commemorative photos at photo studios.

Choose by purpose! Recommended paper size guide

For those who say, "There are so many sizes, I don't know which one to choose!", we will suggest the best paper size for your purpose.

I want to exhibit my work at a photography exhibition or solo exhibition.

A2 size or larger is recommended to attract visitors' attention and allow them to immerse themselves in the world of the work. Main works in particular will have an overwhelming presence if they are in large sizes such as A1, B1, A0, or B0 . When displaying multiple works, combining large and small sizes will create rhythm and depth in the exhibition.

I want to decorate it as a room interior.

Choose a size that suits the size and atmosphere of your room. A4 and 6-cut sizes fit well on the wall or placed on a shelf, and are standard sizes that blend in well with any space. If you want to add a little accent, we recommend A3 size . If your artwork is square, printing it in square size will also give a stylish impression.

As a portfolio or keepsake

For a portfolio that you can hold up and look at closely, A4 or B5 sizes are ideal as they are easy to turn the pages of and allow you to see the details of the work. If you are giving it as a gift to a loved one or want to keep it as a keepsake, you can make it even more special by printing it in 2L or 6-cut size and placing it in a nice frame .

Once you've decided on your size, take the next step

Once you have found the perfect size, it's time to prepare your creation. Here we will answer some frequently asked questions from our customers.

Give your work the best possible shape.

PHOTOPRI is more than just a printing service. Our mission is to bring out the best in artists' expression, and we pour our passion into each and every print. We offer comprehensive support for your creative endeavors, including RGB direct printing with a wide color gamut, genuine ink and premium paper that boasts over 30 years of lightfastness, and attentive support from our professional staff.

First, experience the difference in quality.

See more of PHOTOPRI's commitmentOrder a trial print

summary

This time, we've introduced a detailed list of standard sizes for A, B, and photo paper, as well as their history and how to choose the right size for your purpose. Paper size is like a "frame" that is important for conveying the appeal of your work. We hope this article helps you find the perfect size for your work.

PHOTOPRI will continue to help artists, photographers, and illustrators "give shape to their work." Please feel free to contact us with any questions about printing, including choosing the right size, paper, and display method.