AAC to MP3
Free AAC to MP3 converter for .aac and .m4a files. Unlimited, no sign-up, and the conversion runs in your browser, so the audio is never uploaded.
Your file is converted in your browser and never uploaded to our servers.
How to convert AAC to MP3
Drop the file, match the bitrate to the source, save. Nothing leaves this tab.
- 1
Add the .aac or .m4a file
Drag it onto the box or tap to browse. A bare AAC stream from a recorder and an M4A from iTunes or a phone are both read the same way.
- 2
Pick a bitrate at or above the source
192 kbps is preselected. If the AAC was 256 kbps music, choose 320; for a 64 or 96 kbps voice file, 128 is already enough.
- 3
Save the MP3
The first run fetches the converter, about 9 MB, and the browser caches it. The result keeps the original name, so interview_take2.aac becomes interview_take2.mp3.
What this AAC converter does differently
Converted on your device
FFmpeg runs in the tab as WebAssembly and reads the file from your disk. There is no upload, so there is no server copy waiting hours to be deleted.
Raw ADTS streams and M4A alike
In our 2026-10-24 test runs, a raw ADTS .aac file and an AAC .m4a both came out as valid MP3 files. You don't need to rewrap the .aac first.
Mono stays mono
Channel count and sample rate are carried over from the source. A one-voice recorder file is not padded into fake stereo, so its MP3 stays small.
No account, no counter
Free with no daily limit, no watermark and no email. Convert a whole folder of recordings, one file after another.
Raw .aac vs .m4a vs .mp3: what you are holding
A .aac file and a .m4a file can hold the same sound. What differs is the wrapper around it.
| Raw .aac (ADTS) | .m4a (AAC in MP4) | .mp3 | |
|---|---|---|---|
| What it is | A bare AAC stream in small frames, no container | AAC audio inside an MP4 container | MP3 frames, often with ID3 tags |
| Typical source | Recorders, cam exports, stream captures, extraction tools | iTunes, Apple Music, phone voice memo apps | Almost every music library and podcast feed |
| Title and artist tags | Usually none | Full tag and cover art support | Full ID3 tag support |
| Length and seeking | No index, so some players guess the length | Indexed, seeks accurately | Seeks well in nearly all players |
| Older car stereos and MP3 players | Often refused | Sometimes refused | Plays |
Where standalone AAC files come from
Most people who search for AAC to MP3 have a raw .aac, not a song from a store.
Voice recorders and recorder apps
Handheld recorders and some phone apps offer AAC as a space-saving mode. MP3 is the format a transcription service or a colleague's laptop is sure to open.
Dashcam and action cam audio
Some cameras and their companion apps export the soundtrack as a separate .aac. Convert it to keep the cabin conversation or the sound of a ride.
Radio and stream captures
Recording tools for internet radio and live streams often save the raw AAC feed. Many of these are low-bitrate, so 128 kbps MP3 is the right target.
Audio pulled out by another tool
Demuxers and video editors that copy a soundtrack without re-encoding hand you a .aac. Turn it into MP3 here, or start from the video on our extract-audio page.
Car stereos and USB players
Some head units list MP3 and WMA but skip AAC, or only read it inside .m4a. Run AAC to MP3 once and a USB stick of the results plays in nearly all of them.
Editors and upload forms
Some audio editors, podcast hosts and web forms only accept MP3. Converting once saves a rejected upload.
Which MP3 bitrate to use for an AAC file
AAC and MP3 both throw detail away to save space, so AAC to MP3 is a lossy-to-lossy step. The MP3 encoder can only work with what survived the first encode. Nothing you pick here brings back what the AAC dropped.
Start by checking the source bitrate: right-click the file and look under Properties on Windows or Get Info on a Mac, or open it in VLC and use Tools, Codec Information. AAC holds up a little better than MP3 at the same bitrate, so pick the MP3 step at or just above it. A 64 or 96 kbps capture goes to 128 kbps. A 128 kbps recording goes to 192. A 256 kbps music file goes to 320. Going higher only makes the file bigger: about 0.96, 1.44 or 2.4 MB per minute at 128, 192 or 320 kbps.
If every device you use already plays the .aac, keep it as it is. And if you plan to edit, choose WAV and make the MP3 last.
AAC to MP3 mistakes that cost quality or time
Mistake: Choosing 320 kbps for a 64 kbps stream capture.
Do this instead: The extra bits store nothing new. 128 kbps keeps everything the capture has at about 40% of the size.
Mistake: Renaming song.aac to song.mp3 so the car stereo accepts it.
Do this instead: The frames inside are still AAC, so the stereo usually skips the file. It has to be re-encoded.
Mistake: Converting to MP3 and later back to AAC for an Apple device.
Do this instead: Each round trip is another lossy encode. Keep the original .aac and make each format straight from it.
Mistake: Trimming or leveling the MP3 and saving another MP3.
Do this instead: Convert to WAV for editing, then export one MP3 at the end, so the audio is only compressed twice in total.
Mistake: Deleting the .aac originals once the MP3s play.
Do this instead: Keep them. They are the better copy, and a future player may handle them fine.
Privacy, cost and what it won't do
Your recording stays put
Cloudflare serves this page and jsDelivr serves the open-source FFmpeg files. The audio itself is decoded and encoded on your device and goes to neither.
Free, really unlimited
No quota, no paid plan, no sign-up and no watermark on the output.
Limits we know about
One file at a time and the first audio track only. We haven't measured a maximum size; hour-long files are safest in a desktop browser.