Size Guide:

Informational page about sizes:

Our frame sizes always relate to the internal dimensions, meaning that if you order an A4 size frame for example, this will hold an A4 size poster/insert. The external size will be slightly larger and the visible size smaller. As a rule of thumb the visible area of your poster/insert will be approximately 10mm smaller around all four edges, and this can vary depending on the profile (width) of the frame.

See the A-Size illustration to the right to help you visualise the scaling of A sizes or use our handy size converter below to convert units of measure.

Size Converter Tool:

Type a value in any of the fields to convert between units of measure:

Understanding Paper Sizes

Metric Sizes
Metric Name
Size in mm
Size in Inches


841 x 1188

33"1/8 x 46"3/4


594 x 841

23"3/8 x 33"1/8


420 x 594

16"1/2 x 23"3/8


297 x 420

11"3/4 x 16"1/2


210 x 297

8"1/4 x 11"3/4


148 x 210

5"7/8 x 8"1/4


105 x 148

4"1/8 x 5"7/8


52 x 74

2"7/8 x 8"1/4


148 x 210

2"1/8 x 2"7/8

1/3A4 (DL)

99 x 210

3"7/8 x 8"1/4


74 x 210

2"7/8 x 8"1/4

Imperial Sizes
Inch Size
Size in mm
Paper Name

20" x 30"

508 x 762

Double Crown

30" x 40"

762 x 1016

Quad or Quad Crown

25" x 40"

635 x 1016

Double Royal

40" x 60"

1016 x 1524

4 Sheet or Double Quad

1200 x 1800

6 Sheet or Six Sheet

B Series Sizes
Size in mm
Size in Inches


500 x 700

19"3/5 x 27"1/2


700 x 1000

27"1/2 x 39"1/3


1000 x 1400

39"1/3 x 55"1/8

To calculate in cm use mm above and move the decimal point one space to the left: Eg. 210mm is 21cm. All poster frame sizes are defined by the paper insert size. The external frame size is always slightly larger. The visible area is slightly less than the paper size. Do not print critical content too near the edge of the page!

Metric Paper Sizes:

Metric paper sizes are known as International Standard (ISO 216) or DIN (German Standard) paper sizes. They are used in most of the countries in the world - the most important exception being North America. In United Kingdom a few 'inch' sizes are used alongside metric sizes. However US 'letter' and 'legal' sizes are never used - they are universally replaced by A4 size.

US Paper Sizes:
As with other UK suppliers, Red17 do not stock frames to suit the standard North American paper sizes. Sizes are: Letter size: 8 1/2in x 11in (216 x 279mm) Similar to A4 (but wider and shorter) / Legal size: 8 1/2in x 14in (216 x 356mm) Tabloid: 11in x 17in (279 x 432mm) - Similar to A3 (but narrower and taller) Ledger is the landscape version of Tabloid.

The A Series:

This is the everyday paper size commonly used for general printing, business stationery sets, publications, brochures, leaflets and so on.

The scale can get a little confusing as the bigger the number the smaller the sheet is. To get an idea of the scales have a look at the diagram below with a dimensions guide for reference.

All A sizes are scaled directly in proportion with each other, i.e:

  • AO is double the size of A1
  • A1 is double the size of A2
  • A2 is double the size of A3 and so on…

The B Series:

This is a less common paper size and is much larger that the A series, normally used for posters and wall charts. This system is useful for enlarging and reducing documents and as with the A series paper sizes are measured and rounded to the nearest millimetre.

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We are one of the UK’s largest stockists of Display and Presentation products, with over £1M of stock across three sites available for direct dispatch. This, combined with our manufacturing facilities, ensures we are equipped to service orders of any size within very competitive lead times. We have large stocks available for immediate dispatch via third party specialist carriers or by Red17’s own delivery fleet.

Artwork guidelines
We strive to maintain the highest possible quality standards. Our Quality Policy is communicated and explained to all staff to ensure they fully understand the contribution they make.

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