If you are wondering how big is 8x10, its standard size is 8 inches by 10 inches. This makes it much bigger than the more common sizes of snapshots like 4x6, giving more room to show details, Visuals Clipping explains For portrait, family photos, art or decorative prints, an 8x10 size can be helpful. It can also easily be incorporated in most standard frames, which can make it a useful choice when you don't want the photo to be too large to choose.