What is dpi, and why does it matter in the print world?

DPI (dots per inch) is used to describe the resolution number of dots per inch in a printed piece, the higher the number, the more info (dots) are stuffed into a 1-inch area, creating a more vibrant and visually pleasing printed photo. Conversely, fewer dots per inch results in a more blocky/choppy printed photo. See samples.

The goal is to use images with 300 dpi for all printed pieces. There can be exceptions, including photos used in large format displays, pop-up banners, and tradeshow booths. In these cases, the imagery is viewed from more than an arm’s length away, and the pixilation (choppiness) isn’t as noticeable.

So, how can you tell the dpi of your photos? There are a few tricks you can do on your home or office PC/Mac to check the dpi of each photo you plan to use in a printed piece.

On Windows/PC

• Right-click on the image, and select “Properties”
  • A new window will appear, select the “Details” tab
  • What you are looking for is the “Width” and “Height”
  (should be displayed in pixels, for our purposes, pixels per inch (ppi) and dots per inch (dpi) are the same thing)

On Mac

• “Control” click on the image, and select “Properties” or select image and hit “Command I”
  • Under the “More Info” drop down, we are looking for “Dimensions” (should be displayed in pixels, for our purposes, pixels per inch (ppi) and dots per inch (dpi) are the same thing)

So, now that you know the pixel size of your photo, use this formula to determine the size of your photo at the desired 300 dpi size:

Pixels  ÷  300  =  the inches your photo will print at 300 dpi:

Example 3219 ÷ 300 = 10.73” & 4024 ÷ 300 = 13.41”
photo can print up to 10.73” wide x 13.41” tall and still look great!

This isn’t an unbreakable rule, as some photos will look good enough at only 200 dpi, but it gives you a guideline how the final print quality of a photo will look in your next brochure, flyer or poster.