MP3 to CAF

To convert MP3 to CAF, add your files to the drop area above by dragging them in or clicking to choose, and conversion begins automatically the instant they load, since the output is fixed to CAF with no format menu or convert button to press. You can add several MP3s at once, and each converts on its own. When a file is done it appears as a row with its new name, size, an inline player, and a Download button.

Yes — this MP3 to CAF converter is completely free with no signup, no watermark, and no software to install, and it is fully private because every file is processed locally inside your browser by a WebAssembly build of FFmpeg, so your audio is never uploaded to any server. The only download is the converter engine itself, a one-time ~32 MB file that your browser caches so later conversions start instantly.

There is no fixed file size limit because the conversion runs on your own device rather than a server, so the practical ceiling is however much memory your browser and computer have available, and CAF is especially suited to big files since it has no 4 GB size cap. Very large files of several hundred megabytes convert more comfortably on a desktop than on a phone. You can also convert several smaller files in one batch.

No — converting MP3 to CAF cannot improve or restore quality, because your MP3 is already a lossy file and any detail lost when it was first encoded is gone for good, so wrapping it in CAF's lossless ALAC simply preserves the audio exactly as it currently sounds without adding anything back. What you gain is that no further quality is lost from here on. The trade-off is size: the lossless CAF will be noticeably larger than the MP3 it came from.

CAF is Apple's Core Audio Format, and people convert MP3 to it mainly to bring audio into Apple production tools like Logic Pro and GarageBand, or to keep long recordings in a single lossless-wrapped file, since CAF has no 4 GB size ceiling like WAV and AIFF do. Here the CAF container holds ALAC, Apple's lossless codec, so the audio is stored without any additional compression loss. It is the natural choice when your workflow lives inside Apple's audio ecosystem.

It works on any modern browser across Windows, Mac, Linux, iPhone, and Android, with nothing to install because everything runs client-side, though very large files convert faster and more reliably on a desktop or laptop than on a phone or tablet with less memory. The first conversion downloads a one-time ~32 MB engine, which your browser then caches so subsequent conversions on that device start right away.

Yes, you can convert several MP3 files to CAF in one go by dropping them all into the area above at the same time, and each file is processed independently and then listed as its own row with its new filename, its size, an inline preview player, and a Download button. You can play each result in place to check it before downloading. There is no cap on how many files you add, though large batches use more of your device's memory.