Inch and metric print sizes
Print sizes live in two systems, and the sizes that look alike are the ones that cause trouble. Here is every inch size on our list in exact millimetres, and where each nearly matches an A size.
The conversion.
One inch is exactly 25.4mm. To get millimetres, multiply inches by 25.4. To go the other way, divide. That is all the maths you need, and it beats any rounded figure you might remember, such as 2.5cm to the inch, which is close enough for a shelf but not for a frame.
| Size in inches | Millimetres | Shape | Often used for |
|---|---|---|---|
| 12 x 12 | 305 x 305 | Square | Album art, social images |
| 14 x 11 | 356 x 279 | About 5:4 | Traditional photo frames |
| 16 x 12 | 406 x 305 | 4:3 | Phone and compact camera images |
| 18 x 12 | 457 x 305 | 3:2 | Camera images without a crop |
| 20 x 8 | 508 x 203 | 5:2 | Panoramas |
| 20 x 16 | 508 x 406 | 5:4 | Portrait and studio work |
| 30 x 20 | 762 x 508 | 3:2 | Camera images at poster size |
| 40 x 30 | 1016 x 762 | 4:3 | Large wall prints |
| 60 x 40 | 1524 x 1016 | 3:2 | Largest listed size |
Metric figures on price lists are usually rounded, ours included, so treat those as approximate. If a print must drop into an existing frame or recess, give us the exact size you need and do not rely on a size name.
The near-twins.
Most mistakes happen here. Two sizes sound interchangeable, someone swaps one for the other, and the print does not fit.
| These two | The difference | What goes wrong |
|---|---|---|
| A3 and 16 x 12in | 420 x 297mm against 406 x 305mm | A3 is 14mm longer and 8mm narrower, so it will not sit in the other frame |
| A1 and 30 x 20in | 841 x 594mm against 762 x 508mm | A1 is bigger each way, and a different shape |
| A0 and 40 x 30in | 1189 x 841mm against 1016 x 762mm | A very different area, though people treat both as a big poster |
| A2 and 20 x 16in | 594 x 420mm against 508 x 406mm | Similar height, but A2 is 86mm longer |
Why the shape matters more than the units.
Your image has a shape, and a print size has a shape. If they match, nothing is lost. If they do not, something gets cropped, or white borders appear. A camera file at 3:2 fits 18 x 12, 30 x 20 and 60 x 40 with no crop at all. It will lose a little from each end at A1. So the first thing to check is not the number of inches, but whether the proportions line up. Our guide to scaling artwork shows how to adjust a file, and A sizes explained covers the metric side.
Tips for a clean order.
- Pick one system and stay in it through the whole job.
- Quote width first, then height, and say which edge is which.
- When matching a frame, measure the opening, not the outer edge.
- Set your artwork to the exact millimetre size, plus bleed if needed.
Different sizes side by side.
Your questions.
Why do your lists show sizes in inches at all?
Many photographers and framers still work in inches, and common camera and frame shapes were built around them. We list both so that you can order the size you know.
Is 30cm the same as 12 inches?
Not quite. 12 inches is 304.8mm, so 30cm is about 5mm short. That matters if you are filling a frame.
Can I order a size that is not listed?
Tell us the width and height you need and we will quote for it.