Convert MP3 to AAC online
Free, no sign-up, no limits. Drop your MP3 files, get AAC files back in seconds.
1 files converted so far
Drop your MP3 files here
or · multiple files accepted
Local conversion: your files never leave your device.
Why convert MP3 to AAC?
You have a MP3 file that will not open on one of your devices or applications. AAC is more widely supported for your use case: streams extracted from videos, digital recorders, streaming.
How to do it, step by step
- Drop your MP3 fileinto the area at the top of the page (or several files at once). On mobile, tap the area and pick the file from your apps.
- Check the output format: AAC is already selected. For music, 192 kbps is transparent for most listeners and 320 kbps gives the maximum. For voice (memos, podcasts, lectures), 128 kbps is more than enough and halves the file size.
- Start the conversion.The FFmpeg engine loads once (≈ 10 MB), then each file is processed in a few seconds without leaving your device.
- Download your AAC, directly or as a .zip if you converted several files. The name and metadata (title, artist, cover art) are preserved.
The MP3 format (MPEG-1/2 Audio Layer III)
MP3 is the most universal audio format in the world. It plays on absolutely everything: car stereos, phones, TVs, game consoles, MP3 players, browsers, editing software. Its compression is slightly less efficient than AAC, but its total compatibility makes it the safe choice for sharing an audio file.
- Compatible with 100% of devices
- Small file size
- Patent-free since 2017
- Less efficient compression than AAC/Opus
- Irreversible quality loss at low bitrates
The AAC format (Advanced Audio Coding)
AAC is the successor to MP3: at the same bitrate, the sound is better. It is the audio codec of YouTube, Apple Music, digital TV and most MP4 videos. A raw .aac file (without the M4A container) is rarer and less well supported than its .m4a equivalent.
- Better quality than MP3 at the same bitrate
- Standard for video and streaming
- Raw .aac file poorly compatible
- No metadata without a container
MP3 vs AAC comparison
| MP3 | AAC | |
|---|---|---|
| Compression | Lossy | Lossy |
| Typical size (1 min, music) | ≈ 1.4 MB (192k) | ≈ 1.2 MB (160k) |
| Common use | podcasts, music, car stereos, portable players, email attachments | streams extracted from videos, digital recorders, streaming |
| Metadata (title, cover art) | Yes | Limited |
Frequently asked questions
Does converting MP3 to AAC lose quality?
AAC is a lossy compressed format: a conversion always involves re-encoding. At 192 kbps or higher, the difference is inaudible in the vast majority of cases. Just avoid chaining several successive conversions.
Is the MP3 to AAC converter free?
Yes, with no limit on the number of files, no sign-up and no watermark. Each file can be up to 200 MB.
Are my MP3 files uploaded to the internet?
No. The MP3 to AAC conversion is performed by FFmpeg directly in your browser (WebAssembly). Your files never leave your computer or phone.
How do I convert MP3 to AAC on iPhone or Android?
Open this page in Safari or Chrome, tap the drop area, select your MP3 file (from Files, Voice Memos, Downloads or WhatsApp), then tap "Convert". The AAC downloads to your files.
Can I convert several MP3 files at once?
Yes, add all your files in one go. They are converted one after another and a button lets you download everything as a .zip archive.