Photo print sizes: inches, cm, pixels and ratios

The most common photo print is 6 × 4 inches, sold in Europe as 10 × 15 cm. It has a 3:2 aspect ratio like most cameras. For a sharp print at that size, an image needs about 1800 × 1200 pixels. Smartphone photos at 4:3 suit 8 × 6 or 16 × 12 inch prints better.

Updated by the editorial team

Contents of this page

Common photo print sizes

SizecmAspect ratioPixels for 300 dpi
6 × 4 in15.2 × 10.2 cm3:21800 × 1200 px
7 × 5 in17.8 × 12.7 cm7:52100 × 1500 px
8 × 6 in20.3 × 15.2 cm4:32400 × 1800 px
10 × 8 in25.4 × 20.3 cm5:43000 × 2400 px
12 × 8 in30.5 × 20.3 cm3:23600 × 2400 px
16 × 12 in40.6 × 30.5 cm4:34800 × 3600 px
18 × 12 in45.7 × 30.5 cm3:25400 × 3600 px
20 × 16 in50.8 × 40.6 cm5:46000 × 4800 px
24 × 16 in61 × 40.6 cm3:27200 × 4800 px
30 × 20 in76.2 × 50.8 cm3:29000 × 6000 px

In continental Europe the same prints are sold under rounded metric names: 6 × 4 in becomes 10 × 15 cm, 7 × 5 in becomes 13 × 18 cm, 12 × 8 in becomes 20 × 30 cm. Larger metric sizes such as 30 × 40, 40 × 60 and 50 × 70 cm are genuinely metric. For large prints, 150 to 200 dpi is usually enough, because they are seen from further away.

The aspect ratio decides

3:2
DSLRs and mirrorless cameras with APS-C or full-frame sensors, 35 mm film. Suits 6 × 4, 12 × 8, 18 × 12 and 30 × 20 inches.
4:3
Smartphones, Micro Four Thirds and compact cameras. Suits 8 × 6 and 16 × 12 inches.
16:9
Video and the panorama mode on many phones. Suits panoramic prints.
1:1
Square, for example Instagram images. Suits 8 × 8 or 12 × 12 inches.

When the image ratio and the print size do not match, part of the picture is cut off or a white border appears. You can usually choose which when ordering. To be sure, crop the image to the right ratio yourself first.

Photographic print or inkjet print?

A true photographic print is made on light-sensitive paper that is exposed and developed chemically, as with film. An inkjet or toner print is printed with ink. Both give very good results today. Photographic prints show particularly smooth gradients and last a long time. High-quality pigment inkjet prints on fine-art paper can match or even beat them for longevity and colour range. Labels such as “premium paper” say little, so ask about the process and the paper if in doubt.

Frames for photos

Frames are usually sold by photo size: 7 × 5, 10 × 8, 12 × 8, 16 × 12, 20 × 16 inches, or metric sizes in Europe. Many frames include a mount that surrounds a smaller picture. A 10 × 8 frame with a mount, for example, typically takes a 7 × 5 photo. For ISO paper sizes there are separate frames. Check whether a frame says “A4” or “21 × 30 cm”, because A4 is only 29.7 cm tall.

Frequently asked questions

How many pixels does a 6 × 4 print need?

About 1800 × 1200 pixels for 300 dpi. Every current smartphone delivers far more.

What aspect ratio is a 6 × 4 print?

3:2. It matches images from DSLRs and mirrorless cameras.

Which print size suits phone photos?

Phones usually shoot at 4:3. Good matches are 8 × 6 and 16 × 12 inches.

Is 10 × 15 cm the same as 6 × 4 inches?

Practically. 6 × 4 inches is 15.2 × 10.2 cm, and labs sell it under both names.