How to Change the DPI of a Photo

What does the acronym DPI mean, and why is it so important when printing photos? How can one easily increase the DPI in an editor to avoid poor print quality?

What Is DPI?

This is nothing more than the number of dots per inch of an image. So the acronym means simply “dots per inch.” Their number allows one to assess the quality of an image to be printed. It is by taking into account this parameter that you can determine whether the image will have a good quality after printing. The size in pixels indicates how many dots the image has, whereas the DPI indicates the size of the dots. The smaller these dots are, the clearer the picture is.

Accordingly, two photos of the same size, say, 640×360 pixels, but with a different DPI value, will look completely dissimilar. In practical terms, the smaller the DPI value, the more the image is blurred.

How to Increase the DPI of a Photo

One can easily do this in a graphics editor such as Gimp, Photoshop, or even Paint. However, one should keep in mind that while increasing the DPI, we must preserve the original size of the photo to avoid a quality loss.

How one can accomplish this?

Changing the DPI in Photoshop

If you have this Adobe app, changing the DPI of a photo will be a very simple affair.

  • Open a photo in Photoshop.
  • On the panel, select Image, then Image Size.
  • Uncheck the Resample checkbox. After making sure that you have pixels and inches selected in the Resolution field, enter the DPI value that you see fit. The image size will decrease, but given the file size is large enough, this should not be a problem.

It is also worth adding that it makes no sense to increase the DPI above the maximum allowed value by the printing device.