DPI: Photo 5 x 7

Use this calculator to find out how many pixels (resolution) an image should have to be printed at a certain size.

Print Dimensions

Net dimensions (no bleed)
127 mm x 177.8 mm = 22580.6 mm2aspect ratio: 0.714 (diagonal: 218.5 mm)
12.7 cm x 17.78 cm = 225.81 cm2aspect ratio: 0.714 (diagonal: 21.85 cm)
5 inch x 7 inch = 35 inch2aspect ratio: 0.714 (diagonal: 8.6 inch)

Print Pixel Size

Dots-per-inch
Printer resolution = 300 dpi = 118 dots/cm
Printer pitch = 85 µm / micrometer (size of 1 pixel)
Net dimensions (no bleed)
1500 px x 2100 px = 3.2 megapixels
= aspect ratio 0.714

Some examples

References