How do MP3 and AACcompare? Here's everything you need to know to choose the right format — and how to convert between them.
MPEG Audio Layer III
MP3 is the most popular audio format in the world. It revolutionized digital music by compressing audio files to a fraction of their original size while maintaining good quality. Nearly every device and application supports MP3.
Advanced Audio Coding
AAC is the successor to MP3, offering better sound quality at lower bitrates. It's the default audio format for Apple Music, YouTube, and most streaming platforms.
| Specification | MP3 | AAC |
|---|---|---|
| Full name | MPEG Audio Layer III | Advanced Audio Coding |
| Extension | .mp3 | .aac |
| MIME type | audio/mpeg | audio/aac |
| Category | Audio | Audio |
| Developer | Fraunhofer Society / Moving Picture Experts Group | ISO / Fraunhofer / Dolby / Sony / Nokia |
| Year introduced | 1993 | 1997 |
| Compression | Lossy | Lossy |
AAC offers better quality at the same bitrate — it's the modern evolution of MP3. But MP3 has unbeatable compatibility. For Apple devices, AAC is native. For everything else, MP3 is the safest bet.
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