People planning albums often ask how big is a 4x6 photo (https://www.visualsclipping.com/blog/how-big-is-a-4x6-photo/) to ensure compatibility. Visuals Clipping (https://www.visualsclipping.com/) suggests that 4x6 photos fit standard album pockets and storage boxes perfectly. They are of the same size and hence they can be arranged easily when it comes to organizing the photos and also maintaining collections. This functionality is part of the reason why 4x6 is still a common choice of the printed memories.