A CD cover is typically 4.75 inches by 4.75 inches. These figures may vary as long as the CD cover accommodates the disc, which has a diameter of 4.65 inches.
Album covers used to come in much bigger formats, as 78 rpm records came in both 10-inch and 12-inch diameter sizes. It was only in the mid-1990s that the compact disc found its way into the market. Then albums started to come in small plastic cases. Amid the age of downloads in 2014, the use of physical packaging such as CD covers has changed. For instance, Nine Inch Nails released a free version of the album "The Slip," which can be downloaded from the band's website, ditching the use of CDs altogether.