How to Convert AAC to MP3 with iTunes

convert AAC to MP3
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Songs from the iTunes Store and Apple Music are created using AAC digital audio format. AAC generally delivers better sound quality and smaller file sizes than MP3, but some people still prefer MP3. If you're one of them, you may want to convert your music from AAC to MP3.

Lots of programs that offer this feature, but you don't need to download anything new—and you definitely don't need to pay for anything.

You've already got the program you need: iTunes. There's an audio-file converter built into iTunes that you can use to convert AACs to MP3s.

Change iTunes Settings to Create MP3s

The first thing you need to do is make sure iTunes' file conversion feature is set to create MP3 files (it can create many kinds of files, including AAC, MP3, and Apple Lossless). To do this:

  1. Launch iTunes
  2. Open Preferences (on Windows, do this by going to Edit -> Preferences. On a Mac, go to iTunes -> Preferences)
  3. Click the Import Settings button towards the bottom of the General tab. You'll find it next to the When a CD is inserted drop-down
  4. In the Import Settings window, choose MP3 Encoder from the Import Using drop-down
  5. You should also make a choice in the Setting drop-down. The higher the quality setting, the better the converted song will sound (though the file will be bigger, too). I'd recommend the iTunes Plus setting, which is 256 kbps. Never use anything lower than the current bit rate of the AAC file you're converting. Pick your setting and click OK 
  1. Click OK in the Preferences window to close it.

How to Convert AAC to MP3

With that setting changed, you're ready to convert files. Here's what to do:

  1. Find the song or songs you want to convert in iTunes. You can select songs one at a time or in a group of non-contiguous files by holding down Control on Windows or Command on Mac while you click each file
  1. When you've selected all the files you want to convert, click on the File menu in iTunes

  2. Then click Convert

  3. Click Create MP3 Version

  4. The file conversion begins. How long it takes depends on how many songs you're converting and your quality settings from step 5 above

  5. When the conversion from AAC to MP3 is complete, you'll have one copy of the song in each format. You may want to hold onto both copies. But if you want to delete one, you'll need to know which is which. In that case, select one file and hit the keys Control-I on Windows or Command-I on a Mac. This pops up the song's information window. Click the File tab. The Kind field tells you whether the song is an AAC or MP3.

  6. Delete the song you want to get rid of in the normal way you delete files from iTunes.

How to Get the Best Sound Quality for Converted Files

Converting a song from AAC to MP3 (or vice versa) can result in a slight loss of sound quality for the converted file. That's because both formats keep the file size small by using compression technologies that reduce some sound quality. Generally, most people don't notice this compression. 

This means that AAC and MP3 files are already compressed when you get them. The song gets further compressed when you convert it to a new format.

You may not notice this difference in audio quality, but if you've got great ears and/or great audio equipment, you might.

You can ensure the best audio quality for your files by converting from a higher-quality original, rather than a compressed file. For example, ripping a song from CD to MP3 is better than ripping it to AAC and then converting to MP3. If you don't have a CD, perhaps you can get a lossless version of the original song to convert.