| MP3 | AAC | |
|---|---|---|
| Compression | Lossy | Lossy |
| Metadata | ✓ | ✓ |
| Open / royalty-free | ✓ | - |
| Defined by | - | Apple / MPEG |
| Since | 1993 | - |
| Best for | music and podcasts for any device | Apple devices and streaming |
MP3
The universal lossy audio format.
AAC
AAC audio in an MP4 container. Apple's default; better than MP3 at the same bitrate.
Questions
MP3 or AAC: which is smaller?
It depends on the content; see our measured benchmarks on the conversion pages.
Can I convert MP3 to AAC?
Yes, in your browser, nothing uploaded.
And AAC to MP3?
Yes, as well.