What Audio Format Can the iPhone Play?

The most common format for sharing songs and other audio is the MP3 format. MP3 files are compressed versions of an original audio track that remove inaudible portions of the composition to save space. This format is supported by the iPhone 4, as long as the MP3 has a bitrate of 8 to 320 Kbps. MP3 VBR files, which possess a variable bitrate, are also supported.

Files in the Advanced Audio Coding (AAC) format are the default audio format that Apple uses for its iTunes online music store, which provides the majority of the paid audio content to users of the iPod and iPhone. The iPhone 4 supports AAC files with bitrates of 8 to 320 Kbps. The AAC audio format was designed to improve upon the performance of the older MP3 technology. The High-Efficiency Advanced Audio Codec (HE-AAC) format compresses audio to about one-third the size of a typical AAC or MP3 file while maintaining quality. This format would allow for many more songs to be placed on your iPhone 4 in comparison to other types of files, but is typically used for streaming audio over the Internet.

Files in the WAV audio format are often the uncompressed versions of files found in the MP3 or AAC formats. WAV files are significantly larger than MP3s and other compressed formats, and generally represent about 10 megabytes (MB) per minute of music. The WAV format offers CD-quality sound for the iPhone 4, but greatly limits the amount of songs that can fit on the device's internal memory. While WAV files are typically the standard for uncompressed audio on Windows PCs, AIFF files, which are also supported on the iPhone 4, represent the equivalent format for Apple's line of Macintosh computers.

The iPhone 4 also supports the Apple Lossless audio format, which attempts to provide music in the way the artist intended with zero quality lost from the original recording. These files are very large and are typically used by music aficionados or those that are major fans of a particular artist. Additionally, the iPhone 4 supports files related to Audible music software. This includes files in the Audible format 2, 3, 4, Audible Enhanced Audio, AAX and AAX+. Audible offers iPhone 4 users the ability to listen to books on their phone and these formats cater to files that contain only speech.