It's basic math-just divide the number of pixels by the DPI. Print the same image at 180 dpi and it will be 10 inches wide. So, if you print an 1800 pixel wide image at 300 dots-per-inch, the printed image will be six inches wide. A pixel in a digital image is equivalent to a dot in a print. Most good home printers can output at 300 dpi, which is the recommended minimum for high-quality printing, and professional printers much higher. For a Wallet-size print, the image resolution should be 320 x 240 pixels. In simple terms, a higher DPI means a higher quality print. For a 20 x 30 print, the image resolution should be 1600 x 1200 pixels minimum.

You need to understand how DPI works because it controls the two most important things in printing:

The DPI setting determines how many dots the printer drops onto every square inch of the image-300 dpi means 300 dots of ink, while 150 dpi is half as much. DPI stands for 'dots-per-inch,' and is a specification for printing and for setting the print resolution of an image.Ī print is made from millions of tiny dots of ink.

Resolution for picture sizes dpi