12 x 18 Paper Size, Dimensions and Format (Common US Press Sheet series)

12 x 18

305 x 457


12 x 18


Aspect ratio 1:1.5
Perimeter (P) 1,524 mm
Diagonal (d) 549.43 mm
Area (A) 139,385 mm²


The 12 x 18 format measures 305 x 457 mm or 12 x 18 inches. An 12 x 18 paper fromat has an aspect ratio of 1:1.5. The Area of the 12 x 18 paper size is 139,385 mm² or 216 in² with a perimeter of 1,524 mm or 60 in. An 12 x 18 format has a diagonal length of 549.43 mm or 21.63 in. The 12 x 18 size belongs to the Common US Press Sheet series. In the Common US Press Sheet series there are a total of 13 paper sizes.

What size is 12x18 paper?

So what paper size is 12x18? The answer to what size is a 12x18 paper is exactly in the question itself: 12x18 inches. The 12x18 inches paper size in millimeters (mm) is 305 x 457 mm. 

The size of 12x18 paper is actually more popular than the name itself, this is because there are other more popular paper names with the same size. One of them is from the Architectural paper series and is referred to as Arch B or Architectural B Paper which is mostly used for different digital printing projects.

12x18 paper size in other units:

  • 30.5 x 45.7 cm
  • 0.3 x 0.46 m
  • 864 x 1296 pt
  • 72 x 107.9 pc
  • 3602 x 5398 px

(You can also find every other paper size in different units by selecting the desired unit above at the top right corner of the website.)

12x18 paper size printer

There are many personal and professional printers that support a 12x18 paper format and size. For example some in-home personal printers that support a 12x18 paper size format can be found in this article from pcmag.com. There are also professional large format color multifunction printers from xerox.com.

What is 12x18 paper used for?

Although there are a lot of other paper sizes for every kind of printing and copying need, the 12x18 paper size is most often used in:

  • Booklets
  • Business proposals
  • Advertisement
  • Announcements
  • Posters
  • Frames

12x18 paper is not the most popular paper size out there. In fact the 8.5 x 11 paper size is more popular in many fields. 12x18 paper is still useful for many types of projects. 

It first started in the architectural industry for planning projects, drawings and blueprints and it did a great job in these fields. This is because the 12x18 paper has an aspect ratio of 1:1.5 which provides a wide or long surface area and this is exactly what nicely accommodates an architectural project and other business applications like booklets, posters, frames and more. The large area of the 12x18 paper also accommodates multiple copies of a component or design such as invitations, business cards and more, therefore you can cut them to have many single copies with one print.

12x18 paper size name

Although we categorized the 12x18 paper size in the Common US Press Sheet series, the 12x18 format has also other names and categories. In fact the 12x18 paper size originated from the architectural industry therefore there is also a paper format from the Architectural series called Arch B or Architectural B which has the same size 12x18 inches or 305 x 457 millimeters. 

Another paper that is almost if not identical to the 12x18 paper size is the Extra Tabloide paper size which belongs in the Colombian paper series. It has a 12x18 inches size or 304 x 457.2 mm.

What frame should I get for a 12x18 poster?

To get it right with the frame of a 12x18 poster, image or whatever design you are thinking to print, you should not get a 12x18 frame but instead get a 13x19 inches frame or larger. Even if you want to get a frame with a mat, the mat should be 12x18 inches large and the frame should be equal to 13x19 inches large or greater.

Frequently Asked Questions

The size of an 12 x 18 paper is 305 x 457 mm

The size of an 12 x 18 paper in inches is 12 x 18 in

The half size of an 12 x 18 paper is 152.5 x 228.5 mm or 6 x 9 in

The aspect ratio of an 12 x 18 is 1:1.5

The area of an 12 x 18 paper is 139,385 mm or 216 in

The perimeter of an 12 x 18 paper is 1,524 mm or 60 in

The diagonal measurement of 12 x 18 paper is 549.43 mm or 21.63 in

Other Common US Press Sheet Paper Sizes →

There are a total of 13 Common US Press Sheet Paper Sizes.