Convert WebM to WAV
Decode the audio in a WebM into an uncompressed WAV. WebM carries Opus or Vorbis, two codecs browsers handle well and audio software often does not, so this is usually a recording saved from a browser on its way into an editor or a transcription tool that wants raw samples rather than a codec it has never heard of.
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Add to Chrome — freeDrop your WEBM file here, or click to browse
Up to 50 MB. Deleted automatically after 30 minutes.
What it does
- The video stream is discarded, not re-encoded
- Decodes both Opus and Vorbis audio
- Uncompressed 16-bit PCM output
- No watermark and no sign-up
How to use WebM to WAV
- 1
Add the WebM
Drop the file in or choose it from your computer. The 50 MB upload cap applies, so long meetings may need trimming.
- 2
Convert
The video is dropped and the Opus or Vorbis audio is decoded to 16-bit PCM and written as a WAV.
- 3
Import it
The WAV loads into every editor and transcription tool, including those that do not read Opus.
An excellent codec that audio software never adopted
WebM's audio is Opus, or Vorbis in older files. Both are open, both are good, and Opus is genuinely among the best audio codecs available — it beats MP3 comfortably at any bitrate and is what voice chat and messaging applications use almost universally.
None of that helps if the software you need to open the file with has never implemented it. Browsers moved quickly; audio editors, transcription engines and analysis tools largely did not. The result is a recording that plays perfectly in the browser that made it and will not import into the application you want to work in.
Since browser-based meeting and recording tools produce WebM by default, this comes up far more often than the format's obscurity would suggest.
How it works
The video track is discarded and the Opus or Vorbis audio is decoded to 16-bit PCM samples, written into a WAV with no further processing. Nothing encodes on the output side, which is why every piece of audio software reads the result and why the file is large.
Skipping the video is what makes this quick — in a screen recording the frames are nearly all of the bytes.
When not to decode at all
If whatever receives the audio can read .opus, extracting the track without
touching it is strictly better. It is instant, and it is bit-for-bit the audio the
browser recorded, because no decoding or re-encoding happens. VLC, foobar2000,
most Linux players and recent versions of several editors handle Opus, and ffmpeg
will do the extraction in one command.
Decode to WAV when the tool wants uncompressed samples, which analysis and transcription software usually does and which is the common case here.
Size, and the mono question
Uncompressed stereo is about ten megabytes a minute regardless of content, so an hour-long recording is around six hundred megabytes.
Browser-recorded meetings are worth a moment's thought here. Several people on separate microphones, mixed into one stream, produce something that is stereo in name only — there is no spatial image to preserve. If the transcription tool accepts mono, taking it halves the file and costs nothing that matters for speech.
Examples
A browser-recorded meeting for transcription
Browser-based meeting tools record WebM. Transcription engines used in research and legal work frequently accept WAV only.
Audio from a saved clip for an editor
Opus will not import into many audio editors at all, and older ones do not read Vorbis either. Uncompressed samples always import.
Frequently asked questions
Why will my editor not open a WebM directly?
Because of the audio codec rather than the container. WebM carries Opus or Vorbis, and while browsers adopted both quickly, audio software largely did not. Opus in particular is a recent, genuinely excellent codec that voice and messaging applications use everywhere and that many editors still cannot import. Decoding to PCM removes the question.
Does the audio improve by becoming uncompressed?
No. Opus and Vorbis are lossy, so the encoder discarded what it judged inaudible before the file existed, and that is not recoverable. Decoding reproduces exactly what the WebM holds at full precision. The file gets larger and more widely accepted, which is the entire benefit.
Is there a lossless way to get the audio out?
Yes, if the destination reads Opus. Copying the Opus track straight out of the WebM into an `.opus` file is instant and completely lossless, because nothing is decoded or re-encoded, and ffmpeg does it in a second. Choose WAV when the tool genuinely wants uncompressed samples, which is the usual reason anyone is here.
How big will the WAV be?
About ten megabytes a minute in stereo, whatever the content. A one-hour meeting recording becomes roughly six hundred megabytes. Most browser-recorded meetings are effectively mono anyway — one microphone per person, mixed — so if your transcription tool accepts mono, converting to mono halves it at no meaningful cost.