Hi Laurie,
Images themselves don’t have a DPI. There is a DPI stored in the image’s EXIF data, however this is meaningless (you can learn more here).
DPI refers to how many dots there are per inch when printed, and the smaller you print an image, the higher the DPI will be. So, a 1650×2550 image will have a DPI of 300 when printed at 5.5×8.5 inches. When printed at 2.75×4.25 inches, the same image will have a DPI of 600.
I hope this is clear. Please let us know if you have any further questions!
