MKV to WEBM Converter
Convert MKV to WEBM using your browser's own media codecs — no upload, no watermark, no size limit. Drop a MKV file below — the whole conversion runs on your device.
Drop files, or click to browse
MKV files only — processed one at a time
Frequently asked questions
Is this MKV to WEBM converter free?+
Yes, with no watermark and no account. The engine runs locally in your browser, so there's no server queue limiting usage.
Is my video uploaded to a server?+
No. Orbfile uses your browser's own built-in media codecs (via the WebCodecs API and Mediabunny), so encoding happens entirely on your device.
How long will it take?+
It depends on your device and the video's length and resolution — expect roughly real-time to a few times real-time for typical clips.
Is there a maximum file size?+
There's no fixed upload limit — since everything runs on your device, the practical limit is your browser's available memory, which handles typical clips and even fairly long recordings without issue.
How do I convert MKV to WEBM?+
Drop your MKV file into the box above — Orbfile re-encodes it to WEBM using your browser's own codecs and gives you a download link when it's done.
About MKV and WEBM
What is MKV?
MKV (Matroska) is a flexible open container that can hold multiple audio tracks, subtitles, and chapters alongside the video.
Full MKV format guide →What is WEBM?
WEBM is an open, royalty-free video format built for the web, typically using the VP9 codec for strong compression at small sizes.
Full WEBM format guide →People usually reach for this conversion because WEBM offers excellent compression for web delivery, sidestepping a real MKV weak spot: not natively supported by some phones and TVs without an app. It's especially useful for embedding video on websites.
How it works
- 1
Drop your file in
Drag your video onto the box above, or click it to browse — there's no account to create and no upload to wait on.
- 2
Pick your settings
The output format is already set for this page — just adjust any extra options shown, if there are any.
- 3
Download the result
Your browser processes everything locally and hands you a download link the moment it's done — nothing was ever sent to a server.
Is it private?
Everything happens locally, inside this browser tab. Your video is read from disk, processed with WebAssembly running on your own device, and handed back to you as a download — it's never transmitted anywhere, so there's nothing to intercept and nothing stored on a server.
Common use cases
- Embedding video on websites
- Keeping page load times low
- Uploading a clip to social media
- Sending a video over email or chat
Supported formats
This is one of many pairings the video toolkit handles. In total it covers:
Related conversions
Format details
About MKV files+
MKV (Matroska) is a flexible open container that can hold multiple audio tracks, subtitles, and chapters alongside the video.
Matroska was designed from the ground up as an open, extensible container, meaning a single MKV file can bundle several audio tracks (say, multiple languages), several subtitle tracks, and chapter markers, all switchable during playback — something older containers like AVI and even MP4 handle less gracefully. That flexibility made it the format of choice for archiving TV shows and films with multiple language options, though a handful of phones and streaming devices still expect MP4 and need MKV converted first.
How to open a MKV file
Opens readily in VLC Media Player. For real editing, use DaVinci Resolve, Adobe Premiere Pro (with an extension).
Good for
- supports multiple audio/subtitle tracks in one file
- open format, no licensing fees
Watch out for
- not natively supported by some phones and TVs without an app
About WEBM files+
WEBM is an open, royalty-free video format built for the web, typically using the VP9 codec for strong compression at small sizes.
Google introduced WebM alongside WebP as a royalty-free alternative built specifically for the browser, most commonly pairing the VP9 (or newer AV1) video codec with Opus audio in a lightweight container. That combination tends to compress noticeably better than the more universally-compatible H.264/MP4 pairing, which is why WebM shows up heavily in web video embeds and platforms like YouTube use it internally, even when they serve MP4 for broader device compatibility.
How to open a WEBM file
Opens readily in Chrome, Firefox, Edge (native), VLC Media Player. For real editing, use DaVinci Resolve, Adobe Premiere Pro (with an extension).
Good for
- excellent compression for web delivery
- royalty-free, no licensing overhead
Watch out for
- less commonly used than MP4 outside web contexts
Need a different format? Try the full Video Converter, or explore all video tools.