How to Convert 300 DPI Inches to Pixels Printing

1. Multiply the width, in inches, of the printout by 300 to calculate the number of horizontal pixels. As an example, to fill an 8.5-by-11-inch page, you would need a horizontal resolution of 2,550 pixels.
2. Multiply the height by 300 to calculate the vertical pixels required. In the example, you would need a vertical resolution of 3,300 pixels. Together, you would need an image with a combined resolution of 2,550 by 3,300 pixels.
3. Multiply these two calculations to determine the total number of pixels. In the example, this produces 8,415,000 pixels. To convert this number into a more common unit, move the decimal place six places to the left to produce 8.4 megapixels. This means you would need at least an 8-megapixel camera to take pictures that can clearly print onto a standard page at 300 DPI.