What Is the Best Format For Your Music: AAC or MP3?

Which encoding format is best for the average listener?

shuffle music on iphone

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When ripping music from a CD, you should save your songs in either the AAC or MP3 format. In terms of audio quality, there is little difference between the two file types. The encoding speed you select has a greater impact on how the track ultimately sounds.

Information in this article applies broadly to all devices capable of playing digital music files. Sound quality will vary depending on your device's speakers.

Do AAC and MP3 Files Work on All Devices?

AAC is the preferred audio file format for iTunes and Apple Music, but it is possible to play ACC files on Android and Windows computers. Likewise, the MP3 format also works on any operating system. You should have no problem playing either file type on any device.

AAC vs. MP3: Sound Quality and File Size

To examine the differences between the formats, let's compare the song "Wild Sage" by The Mountain Goats encoded in each format at three different speeds: 128 Kbps, 192 Kbps, and 256 Kbps. The higher the Kbps, the bigger the file, but the better the quality.

Format Encoding Rate File Size
MP3 256K 7.8MB
AAC 256K 9.0MB
MP3 192K 5.8MB
AAC 192K 6.7MB
MP3 128K 3.9MB
AAC 128K 4.0MB

AAC vs. MP3 at 256 Kbps

The MP3 and AAC versions sound nearly identical. The MP3 version is 1.2MB smaller.

AAC vs. MP3 at 192 Kbps

These versions sound a bit muddied compared to the 256 Kbps versions; however, there's no clear distinction between AAC and MP3. The MP3 is almost 1MB smaller.

AAC vs. MP3 at 128 Kbps

The AAC file is a bit clearer and brighter than the MP3, which suffers from slight muddiness and slurring some sounds together. The file sizes are almost exactly the same.

AAC vs. MP3: Which Is Better?

While there are differences in the sound waves of the files, they sound roughly equivalent to the ear. Though there may be a bit more detail in the 256 Kbps MP3, it's difficult for an untrained ear to discern. The only place you're likely to hear a difference is in the low-end 128 Kbps encodings, which aren't recommended. While MP3 files tend to be smaller than AAC files, the differences again are not substantial.

Audiophiles vs. Compressed Music

Most audiophiles who place great value on the best possible sound quality tend to detest MP3, AAC, and other digital audio formats because they use compression to create smaller files. The trade off is that the very highest and lowest ends of the sound range are lost. Most average listeners don't notice the loss, but it can be a deal breaker for audio aficionados. If you're used to listening to music on an iPhone or Android device, then you'll probably be satisfied with either AAC or MP3.