Digital Photos

The size of your digital photo comes from the aspect ratio which the photos were taken with.

Digital photo files usually do not have the same aspect ratio as classic analogue photo prints (e.g. 10 x 15 cm), which is because the image sensors of (compact) digital cameras have different aspect ratios to analogue films.

So that all of your digital photo can be seen on the photo paper it is proportionally adjusted to fit (reduced in size). Therefore the photo length is variable depending on the file. If your image file has an aspect ratio of 3:4, which is the most common setting for digital cameras, you get a size of 9 x 12, cm, 10 x 13.5 cm, 11 x 15 cm, 13 x 17 cm or 20 x 27 cm.

1. Determining the aspect ratio
You can determine the aspect ratio from the number of pixels.
Simply divide the larger number of pixels by the smaller number of pixels.
For example: 3264 x 2448 pixels
You calculate: 3264/2448 = 1.33 = 4/3
This means: your photo has an aspect ratio of 4:3

Other common aspect ratios:
(Your calculation then results in one of the values below instead of 1.5).
4:3 = 1.33 – standard digital format
16:9 = 1.78 – panorama photo, is developed with white edges
5:3 = 1.67
1:1 = 1 – square photo. The number of pixels is identical for both sides
2:3= 1.5 – classic analogue photo format

2. Calculating the photo size
For example: 3264 x 2448 pixels; aspect ratio 4:3
Assumption: You choose the 10 cm format.
As a result the shorter side of your photo is 10 cm long.
How long will the other side be?
Calculation method: 10 cm * 4/3 = 13.3 cm
Answer: The other side is adjusted to your photo’s aspect ratio and is 13.3 cm.