How to Calculate Megapixels

By Ty Arthur

Digital cameras tout their higher and higher megapixel ratings as a selling feature. But what exactly is a megapixel and how do is a megapixel rating calculated?

Things You'll Need

  • Calculator

Step 1

To understand how to calculate megapixels you first must understand what they are. Images taken by your digital camera are composed of very small dots called picture elements, or pixels for short. Arranging the pixels together along a horizontal and vertical axis creates a picture.

Step 2

A megapixel is a rounded number found by multiplying the total number of horizontal pixels by the total number of vertical pixels.

Step 3

The number of horizontal and vertical pixels will depend on the size of the image. A digital camera with a 5 megapixel rating takes pictures that are 2,592 pixels wide by 1,944 pixels tall.

Step 4

2,592 pixels multiplied by 1,944 pixels equals 5,038,848 pixels, which is rounded to 5 megapixels.

Step 5

The same equation can be used to calculate any megapixel rating. For example 3,000 horizontal pixels multiplied by 2,400 horizontal pixels equals 7,200,000 pixels, or 7 megapixels.