Convert MP3 to AAC
If something asks for a .aac file, convert your MP3 here, on your own computer, without uploading it.
- Never uploaded
- No size limit
- No sign-up
- Free
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Quick answer: To convert MP3 to AAC, drop the MP3 into the tool at the top of this page and press "Convert to AAC". You get a plain .aac file. It happens in your browser, so the file is never uploaded. It is free, with no sign-up and no file size limit. The sound does not get better: both are compressed.
Updated
How it works
- Drop your audio fileMP3, WAV, FLAC, OGG and more. It stays on your computer.
- ConvertYour sound is saved in the compact format, or copied as it is where it already fits.
- Download the fileOpens in most phones, players and editors.
A .aac file, not an .m4a
The result is a plain .aac file, not one that ends in .m4a. If the app asks for .m4a, use MP3 to M4A. To go the other way, see AAC to MP3; for how the two compare, AAC vs MP3.
It does not improve the sound
AAC and MP3 are both compressed. Converting between them cannot restore detail already lost. Do it when a form or app needs AAC, not to improve quality.
Measured, not promised
Measured on 21 Oct 2026 in Chrome on a 2019 Intel MacBook (an older laptop) with a 20-second sample. Newer computers are faster; real files vary. More results.
Why your audio never leaves your computer
Your audio is converted by your own computer, inside this tab, and never uploaded. That is why there is no length limit and no sign-up. How it works.
Questions
Can I go back to MP3?
Yes: AAC to MP3.
Does it work for WAV?
Yes. Drop a WAV, and you get a .aac file.
Can I convert several files at once?
Yes. Choose or drop several files together. They are converted one after another with the same settings, and you can download each one or all of them in one ZIP.
Is my file uploaded?
No. It is converted inside this browser tab and saved straight back to your computer.
Can I use a video file?
Yes. Drop a video and you get its sound.