To answer the question how big is a 4x6 photo, 4x6 is a relatively small size when compared to larger portrait and wall-print sizes. This size works well on smaller display spaces and their associated desks and shelves without taking over the space, as Visuals Clipping explains. It's also very easy to store many photos side by side in an album or collection of frames. 4x6 is a great size for everyday photos that must be viewable and easily organized and stored.