Compress M4A audio online with predictable presets and matching M4A output.
Choose an M4A file from your device.
Pick a compression preset before starting the task.
Get the compressed file when the background worker marks it complete.
The compressed M4A file keeps a matching output format for reliable playback.
Choose the smallest file, a balanced result, or better quality depending on your sharing and playback needs.
Large files use multipart upload, then a background worker handles the FFmpeg compression task.