A 4x4 photo size is defined as 4 inches by 4 inches, which converts to about 10.16 x 10.16 cm in metric units. This square format follows a 1:1 aspect ratio, meaning both sides are equal. It is commonly used for photo printing, albums, and frames because it offers a clean and symmetrical appearance for various types of images. https://clippingexpertasia.com/blog/how-big-are-4x4-pictures/