Remove Metadata from WebM — Free, No Upload
WebM is the web-native variant of Matroska — same tag system, same container, restricted to VP8/VP9/AV1 video and Vorbis/Opus audio. Browser-recorded clips (MediaRecorder API), Chrome screen captures, and most Sora/Runway exports use WebM. Cleaning works identically to MKV.
Last reviewed 2026-04-28 · Verified against synthetic + real-world WebM samples
Drop your .webm file
Max file size: ~2 GB (memory permitting)
What leaks in WebM files
- Browser/recording-app identifier in MuxingApp (Chrome, Firefox, ffmpeg.wasm, OBS)
- Title and Description Matroska tags
- TrackUIDs (deterministic per recording session — can fingerprint a specific Chrome instance)
- Encoder strings naming the VP9 / Opus version
Confirming it worked
| WebM carries less to begin with | It is a Matroska subset with a smaller tag set, so there is usually less to remove than in an MP4 from a phone. That is not the same as there being nothing. |
|---|---|
| Check the muxing application | WebM files written by a browser recorder name the encoder and often the browser version. That is the field most likely to survive a careless clean. |
| Screen recordings are the risk | Most WebM files on a machine came from a screen or webcam recording, where what is in the picture matters far more than the container. |
| What it does not remove | Anything visible: notifications, open tabs, email addresses, the contents of a shared window. |
Frequently asked questions
How do I strip metadata from a WebM video?
Drop the .webm in. Same Matroska tag-emptying pipeline as MKV. Output stays WebM.
Does it work on browser-recorded MediaRecorder output?
Yes. Browser-MediaRecorder WebM clips carry a MuxingApp string identifying the browser and OS — we remove that. TrackUIDs are zeroed.
What if my AI-generated video is in WebM?
Some Sora and Runway exports come as WebM with C2PA payload embedded as a Matroska tag rather than an MP4 UUID atom. Our pipeline handles both — Matroska tag clearing is per-element.