What kinds of files can be embedded in a WEBM?

WEBM uses the Matroska container format, which can attach almost any file — subtitles, fonts, images, text, JSON, or other documents. Extraction preserves the embedded bytes exactly.

My WEBM has several attachments — what do I get?

This tool writes the attached file to a single output. When a WEBM embeds more than one attachment, ffmpeg's attachment dump resolves them against the same destination, so keep expectations to the main embedded file; extract archives with many members from a tool that supports per-file output.

Is my WEBM uploaded to a server?

The WEBM is processed in a short-lived environment and is not stored. Download the extracted attachment right away.

What if the WEBM has no attachments?

Then there is nothing to extract and the tool reports an empty result rather than fabricating a file. Corrupt or non-WebM input is rejected with a clear error.

Extract attachments from a WEBM online

Some WEBM files carry more than video and audio. This page extracts attachments from a WEBM — files embedded inside the container using Matroska's attachment mechanism, such as bundled subtitles, fonts, or documents.

How to extract embedded files from a WEBM

Upload a WEBM file up to 80 MB.
Press Convert file.
Download the extracted attachment from the result page.

What you get

The file that was embedded in the WEBM, saved byte-for-byte with its original content. If the WEBM has no attachments, you get a clean empty result instead of a fabricated file.

When this helps

A subtitles track or font is packed into the container
Cover art or metadata files were attached to the video
A distributed WEBM bundles a readme or license alongside the footage

This extracts what is embedded. It does not convert, re-encode, or edit the video itself.