Free tools for your next audio edit
Convert M4A to MP3. Preview before you download.
Make an MP3 from a compatible short M4A recording. Choose a bitrate, compare actual file sizes, and listen to the export locally in your browser. The conversion is free and requires no audio upload.
Convert M4A to MP3
Free · localChoose WAV or a compatible M4A to create an MP3 delivery copy, or MP3 for a new encode. Preview and compare the actual file size before downloading.
A comparison only: this does not automatically choose a bitrate or guarantee acceptance by another service. Check that destination's actual rules.
Your audio stays in this browser. No trimming, fades, normalization, mono downmix, or noise removal is applied. Keep your original; this tool does not promise a smaller file at every bitrate.
Decode, encode, listen
How to convert M4A to MP3
- 01 / OPEN
Choose a compatible M4A
Select a mono or stereo file up to 50 MiB and five minutes. The browser reads it locally. M4A is a container, and support depends on its codec and your browser.
- 02 / ENCODE
Choose an MP3 bitrate
Select 64, 96, 128, 192 or 320 kbps and prepare the export. The browser decodes at 48 kHz; the encoder may use a lower output sample rate at lower bitrates. The output must also fit 50 MiB.
- 03 / CHECK
Preview and download
Listen to the actual MP3 and compare its size with the original. The size limit is a comparison, not an automatic bitrate selector. Keep the original M4A.
Choose the right working copy
What changes when you convert?
MP3 is a new lossy encode. AAC-to-MP3 can discard more information, and Apple Lossless-to-MP3 also discards detail. A larger bitrate cannot restore what was already lost. Tags, artwork and source bit depth are not preserved; codec delay or padding can affect timing.
An MP3 can be larger than the original M4A, especially when the source uses a lower bitrate. Compare the displayed actual bytes and listen at a similar level. This page uses the same local encoder as the audio compressor, which also accepts WAV and MP3.
Try the original stereo test M4A first if you want a format check. If your browser cannot decode the file, use Apple Music or Audacity as described in the conversion guide. For a PCM working file, use M4A to WAV.
MP3 encoder credits
Built with the LAME encoder via lamejs.
The MP3 download uses lamejs 1.2.1 by Alex Zhukov, a JavaScript port of the LAME MP3 encoder. Its unmodified script is served separately. See the attribution and source notes, upstream license notice, LGPL-3.0 and GPL-3.0 texts, and complete upstream source package.
A few useful answers
Free M4A to MP3 converter questions
How do I convert M4A to MP3?
Choose a compatible mono or stereo M4A up to 50 MiB and five minutes, select an MP3 bitrate, then prepare, preview and download the actual export. Browser codec support varies; output must also fit the size limit.
Does this converter upload my recording?
No. The browser reads and decodes the file locally and a local worker encodes the MP3. Download the result before leaving; the utility does not keep a cloud copy.
Does converting M4A to MP3 preserve quality?
MP3 encoding is lossy. If the M4A contains AAC, this adds another lossy encode; if it contains Apple Lossless, MP3 discards information. Keep the original and compare the result at a similar listening volume.
Why is my MP3 larger than the M4A?
The original may use a lower or variable bitrate. The tool compares actual file sizes; an MP3 is not always smaller. The selected bitrate, duration, framing and metadata affect the result.
Why will my M4A not open?
M4A can contain different codecs and browser support varies. The file must also be nonempty, mono or stereo, and within the input and duration limits. Try a compatible source or a desktop method in the conversion guide.
Can I upload a WAV or MP3 instead?
Yes. This converter uses the same encoder as the audio compressor and also accepts supported short WAV and MP3 files. MP3 input is re-encoded; it is not a lossless copy.
After preparing your audio