MP3 to M4A

Re-encode an MP3 file as M4A — AAC inside an MP4 container, the format iTunes and the Apple ecosystem use natively. Because the source is already lossy, the re-encode will lose some quality; pick a higher bitrate if you care. Runs entirely in your browser using ffmpeg.wasm — your audio never leaves your device. Expect a few seconds for a 5-minute song.