Free tool

MP3 to M4A converter the format Apple apps prefer.

Drop MP3 files and download M4A versions that iTunes, Apple Music, GarageBand and iMovie take without a fuss, at the bitrate you choose.

Drop audio files here or click to choose. MP3, WAV, M4A, AAC, OGG, FLAC, AIFF, or the sound of a video. Several at once is fine.

Convert to Bitrate MP3, M4A and OGG Channels

MP3 to M4A converter at a glance

content.win converts audio a whole folder at a time, with no daily cap and no file-size wall.

Works with: MP3, WAV, M4A and AAC, OGG and Opus, FLAC, AIFF, and the sound of an MP4, MOV or WebM. Several at once.
Comes back as: MP3, WAV, M4A, OGG or FLAC, the full length, named after the original.
Runs: In your browser.
Limits: No daily limit and no cap on how many files.
Price: Free. No account, no watermark.

Drop the MP3 files in. One or a folder.
Pick a bitrate. 192 kbps matches a typical MP3; 128 kbps is plenty for speech.
Download the M4As. The full length of each, named after the originals.

AAC inside: M4A is an AAC audio file in an MP4 container. It is the native audio format on iPhone, Mac and most video editors.
Ringtones and projects: GarageBand, iMovie and Final Cut take M4A directly. An iPhone ringtone is the same file renamed to .m4r.
Quality: At the same bitrate AAC sounds a little better than MP3. Converting an MP3 cannot add back what the MP3 lost, so match the original bitrate rather than raising it.

Why convert MP3 to M4A?

For an Apple app or device that wants M4A, or a project that needs AAC. The sound is the same; the wrapper changes.

Does the quality improve?

No. A conversion never adds detail. Matching the MP3's bitrate keeps what it had.

Can I make an iPhone ringtone?

Convert at 128 or 192 kbps, trim it to 30 seconds, then rename .m4a to .m4r and add it through Finder or iTunes.

Can I convert several at once?

Yes. Drop the folder and one button downloads every M4A.