How big is the 4R in photography?

The size of the photo is different at home and abroad. The domestic names are 5 inches, 6 inches, 7 inches... which refers to the length of the longer side of the photo; the international names are 3R, 4R, 5R..., the value is taken from the shorter side of the photo.

1 inch = 2.54cm

For example, the size of a 5-inch photo is 12.7cm×8.9cm, converted into inches, that is, 5 inches×3.5 inches

The domestic name is 5 inches (take the long side), and the international name is 3R (take the short side).

The following is a size comparison table of common photos:

Specifications (inches) Dimensions (cm)

8K [1 inch] 2.54×3.81

Passport[1.5 inch] 3.4×4.9

4K[2 inch] 3.6×5.5

3R[5 inch] 8.9×12.7

4R[ 6 inches] 15.2×10.2

5R[7 inches] 12.7×17.8

6R[8 inches] 15.2×20

8R[10 inches] 20.3× 25.4

10R[12 inches] 30.5×25.4

10RW[15 inches] 25.4×38.1