How Video to Audio Works
AnyTool extracts a video's audio entirely in the browser using a self-hosted single-threaded ffmpeg.wasm engine (bundled core, no CDN). When the source audio codec already matches the chosen container (for example AAC into .m4a), a "match source" mode runs -c:a copy to extract the stream losslessly in well under a second regardless of clip length; otherwise the audio is re-encoded to MP3 (libmp3lame), AAC (.m4a), WAV (pcm_s16le) or OGG (libvorbis) at a selectable bitrate. Optional trim (-ss/-t), fade and loudness normalize filters can be applied, and the extracted track is read back as a downloadable blob.
- Runs client-side — the video is never uploaded
- Self-hosted ffmpeg core (bundled) — no CDN
- Instant lossless "match source" stream-copy when codecs align
- MP3, M4A (AAC), WAV and OGG with selectable bitrate
- Optional trim, fade and loudness normalize
- No backend, no watermark, no size cap
