DPI: US Royal

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)
508 mm x 635 mm = 322580 mm2aspect ratio: 0.8 (diagonal: 813.2 mm)
50.8 cm x 63.5 cm = 3225.8 cm2aspect ratio: 0.8 (diagonal: 81.32 cm)
20 inch x 25 inch = 500 inch2aspect ratio: 0.8 (diagonal: 32.02 inch)
1.67 feet x 2.08 feet = 3.47 feet2aspect ratio: 0.803 (diagonal: 2.67 feet)

Print Pixel Size

Dots-per-inch
Printer resolution = 72 dpi = 28 dots/cm
Printer pitch = 353 µm / micrometer (size of 1 pixel)
Net dimensions (no bleed)
1440 px x 1800 px = 2.6 megapixels
= aspect ratio 0.8

Some examples

References