AAC -> MP3 · Local tool
AAC to MP3
Convert an AAC file to MP3 for players that will not open it.
Last updated
How do I convert an AAC file to MP3?
Drop the file onto filetity's converter and it becomes an MP3 in the browser tab, with nothing uploaded. It takes AAC in either form it comes in: a bare .aac stream, or the same audio wrapped in an M4A or MP4 container, which is what Apple software and most recorders produce. Your browser decodes AAC natively, which is precisely the gap this page closes, because AAC support is close to universal in browsers and patchy in older desktop software and car stereos. Worth knowing that this is a step down in efficiency rather than up: AAC generally beats MP3 at the same bitrate, so convert when something will not open the original rather than by default, and the target bitrate is capped at what the source actually spends.
01 / Your device
the file stays here
02 / Browser memory
the work runs locally
03 / Back to you
saved on this device
When you would use this
Situations, not settings.
- A car stereo or an older player
- Browsers decode AAC almost universally and older hardware does not, which is the whole gap this closes.
- A bare .aac stream out of a recorder or a broadcast
- Both the raw stream and AAC wrapped in an M4A open here, because the audio inside is what is being converted.
- Software that lists MP3 and nothing else
- Transcription services and older editors still do this. The target bitrate is capped at what the source spends, so the file does not inflate.
How it works / no cloud
A conversion engine, not an upload form.
AAC turns up either bare, as an .aac stream, or wrapped in an M4A or MP4 container, and both are read here. Your browser decodes AAC natively and the result is re-encoded to MP3 in the page, so nothing crosses the network at any point.
- Offline ready
- Installable app
- No file limit queue
Straight answers
No accordion. Nothing hidden.
- Is it free?
- Yes, with no watermark and no page limit.
- Does it need an account?
- No. There is no account system.
- Is my file processed on my device?
- Yes. The file is read by your browser and never uploaded. There is no server to send it to.
- What formats are supported?
- Bare .aac streams and AAC inside M4A or MP4. MP3 out, or WAV if you want no further loss.
- What are the limits?
- A file with DRM on it cannot be converted by anything running in a browser and is refused rather than producing something broken.
- Does it work on mobile?
- Yes, on any modern mobile browser. Large files are limited by the memory the phone gives the browser.
- Does it work offline?
- Yes, once the page has loaded. The tool keeps working with no network connection.
- What is the difference between .aac and .m4a?
- The codec is the same and the wrapper is not. A bare .aac file is a raw stream with almost nothing around it, and an .m4a puts that same audio in an MP4 container with room for tags, chapters and artwork. Both open here, because the audio inside is what is being converted.
- Is AAC better than MP3?
- At the same bitrate, generally yes, which is why Apple, YouTube and broadcast all use it. That is also why converting to MP3 is a step down in efficiency rather than up. The only good reason to do it is a device or a program that will not open AAC, which usually means a car stereo or something old.
- Should I pick WAV instead?
- If the file is going into an editor, yes. WAV is uncompressed, so nothing further is discarded, at the cost of a much larger file. If the file is going to a player, MP3 is the right answer, because a WAV is roughly ten times the size for audio that will sound the same on a phone or a car speaker.
- Why does my file play here but not in my program?
- Because the browser has a decoder your program does not. AAC support is close to universal in browsers and patchy in older desktop software and hardware. That gap is exactly what this page exists to close, and it is why the conversion can happen locally at all.
- Does the bitrate stay the same?
- Not exactly, and it should not. The target is capped by what the source actually spends, so a 128 kbps AAC will not be given 320 kbps of MP3, which would make a larger file with no more detail in it. What you get is a sensible MP3 bitrate at or below the source's own.
Keep working locally
3 available · more coming