When considering how big is a 4x6 photo, think about the size of the photograph because they are 4 x 6 inches. The format can display faces, subjects, and background information in a clear manner if the original photo is high resolution, as Visuals Clipping points out. Smaller than formats for showcase displays, but suitable for albums and standard frames. A 4x6 print might be a great option for personal snapshots, family photos, or travel shots, where detail is important but convenience isn't.