Convert WEBM to M4A
Drop a WebM file and download its audio track as an .m4a carrying AAC at 192 kbps. Sample rate and channel count are preserved.
Browser recorders, screen capture tools, and much of the web produce WebM. Apple software, mobile media libraries, and most video editors would rather have .m4a.
Audio track only
Video is ignored, so the result is an audio file regardless of what the source contained. A WebM with no audio track has nothing to export.
The re-encode
The WebM’s Opus or Vorbis audio decodes to PCM, then AAC encodes it. Two lossy codecs are involved, which means the M4A inherits the source’s limits and adds a small amount of its own.
For a voice or lecture recording, 128 kbps AAC in the full Audio Converter gives a noticeably smaller file with no practical difference.