If you want to make multiple prints of a photo, you may want to consider a practical size, which may be provided by knowing how big is a 4x6 photo. This is a standard size of 4x6 inches, which is often found on individual photos, event photos, family photos, and small gifts. The small size makes it easy to store, distribute and fit in standard albums or frames, Visuals Clipping explains. It is a practical choice if used to create multiple prints and minimal storage or display space is desired.