DPI is short for Dots Per Inch.

Dots per inch is a measure of spatial printing, video or image scanner dot density, in particular the number of individual dots that can be placed in a line within the span of 1 inch.

**Formula to calculate DPI.**

**Example:**

Letâ€™s say we have a digital image that is 1200 x 1800 pixels and 4 x 6 inches in size.

This means that the image is 1200 dots high and 1800 dots wide, as well as 4 inches high and 6 inches wide.

Therefore, the image’s DPI is 300.