Convert M4A files into the highly efficient Opus format, which excels with speech and low bitrates. Conversion runs right in your browser, so your files are not uploaded by default.
In “Local” mode your file never leaves your device. No uploads, no server – ideal for sensitive recordings.
Pick “Local” for full privacy or “Server” for very large files and every format.
No sign-up, no queue, no watermark. Choose a file, convert, download.
No. Opus is very efficient, but it can't recover detail already lost in the M4A. Since both are lossy, re-encoding tends to lose a little rather than gain.
Mainly for voice recordings, podcasts and web streaming, where Opus sounds great at a small file size.
In modern browsers, many messengers and current players. On older devices, support is limited.
No, conversion runs locally in your browser by default. An optional server mode is available for very large files.