Skip to main content
Echoryte

Local media tool

Extract audio from video in your browser

Extract the audio stream from a conservatively sized video into WAV or MP3 using an on-demand, same-origin WebAssembly engine.

Go to local workbench
Execution
This browser
Output
Extracted WAV or MP3 audio file
Content review
2026-07-20

Browser workbench · no upload

Work on this device

File content stays inside this browser tab.

Preflight ceiling

32 MB

Fixed ceiling · no device-based uplift

The pinned single-thread engine loads from this origin only after Start. The ceiling reduces obvious memory risk; media over 30 minutes, output near 64 MB, or work beyond two minutes is stopped instead of returning a partial download.

Engine licensing: third-party notice · GPL v2 · exact corresponding source

The engine is requested only after Start.

Video-to-audio extraction runs in the same pinned ffmpeg.wasm worker as the audio converter. It disables video output and writes a new audio file in browser memory. There is no upload step, and the heavy engine is absent from the initial marketing bundle.

Workflow

A short, inspectable path

  1. 01Choose a video no larger than the fixed 32 MB ceiling and select WAV or MP3 output.
  2. 02Start extraction; the same-origin engine loads on demand and processes the local File object.
  3. 03Cancel if needed; otherwise download and verify the complete duration before deleting or moving the source video.

What extraction changes

Extraction removes the visual stream and decodes the available audio into the selected output. WAV is fixed at 16 kHz mono PCM to constrain decoded expansion; MP3 quality level 4 prioritizes a smaller listening copy. The engine probes duration before encoding, applies a 64 MB output bound, and rejects boundary-sized output instead of presenting a potentially truncated download. Neither option transcribes or enhances speech.

Why every ceiling is fail-closed

A browser has less predictable memory and thermal headroom than a desktop FFmpeg process. The 32 MB input ceiling never rises from device hints; 30 minutes and two minutes bound media duration and execution respectively. Cancel terminates the worker. Use a reviewed desktop workflow or the main product for larger material rather than trying to bypass these local limits.

Local-data boundary

The video is copied directly from the File object into the local worker file system. No third-party analytics executes on the tool route, and no outcome event receives its name, MIME metadata, duration, or bytes.

Limits worth keeping visible

  • Videos without a decodable audio stream cannot produce an output, and the tool reports that failure rather than substituting silence.
  • The same fixed 32 MB input, 30-minute duration, 64 MB output, and two-minute execution bounds apply on every device. A file below those rejection ceilings can still fail under browser memory pressure.

Reviewed references