AAC vs MP3. | FileStack Blog
Though, AAC files are generally similar in size to MP3s despite being a tad higher in quality. However it's AAC vs MP3 because .AAC files, in their original state, are much higher in quality than any of the other audio file formats on the list. .AAC files are also open-source, which means you don’t need to pay royalties to create and distribute them (unlike .MP3 files).