Convert Matroska to WebM Online Free
Convert Matroska video to WebM format with high-quality encoding. Powered by FFmpeg for reliable transcoding of any resolution.
ChangeThisFile converts your MKV video into the web-native WebM format using FFmpeg server-side processing. WebM is optimized for browser playback and streaming, making it ideal for online content. Files are automatically deleted after conversion, free to use with no registration needed.
Convert Matroska to WebM
Drop your Matroska file here to convert it instantly
Drag & drop your .mkv file here, or click to browse
Convert to WebM instantly
Matroska vs WebM: Format Comparison
Key differences between the two formats
| Feature | Matroska | WebM |
|---|---|---|
| Video codec | Any (H.264, H.265, VP9, AV1) | VP8/VP9/AV1 |
| Container | Matroska | Matroska subset |
| Compression | Depends on codec | Lossy |
| Audio codec | Any (FLAC, AAC, DTS, etc.) | Vorbis/Opus |
| Streaming | Limited | Yes (WebRTC native) |
| Browser support | Minimal native support | Chrome, Firefox, Edge |
| Max resolution | 8K+ | 8K |
| Metadata | Very extensive (tags, chapters, attachments) | Limited |
When to Convert
Common scenarios where this conversion is useful
Device compatibility
Convert Matroska to WebM for playback on devices or software that does not support Matroska natively.
Cross-platform sharing
Share WebM files with collaborators who use different operating systems or media players.
Video editing preparation
Convert to WebM as required by your video editing software's import format requirements.
File size optimization
Re-encode Matroska as WebM to potentially reduce file size while maintaining acceptable quality.
How to Convert Matroska to WebM
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1
Upload your Matroska file
Drag and drop your .mkv file onto the converter, or click to browse. Files up to 50 MB are supported for free.
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2
Server-side conversion
Your file is securely uploaded and converted on our servers using FFmpeg, the industry-standard multimedia framework. This typically takes a few seconds.
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3
Download the result
Once conversion is complete, click Download to save your .webm file. The uploaded file is automatically deleted from our servers.
Frequently Asked Questions
Yes, completely free. Convert Matroska to WebM with no cost, no signup, and no watermarks.
No. Files are automatically deleted immediately after conversion. Nothing is stored or retained.
Yes. Files are transferred over encrypted HTTPS connections. Your data is protected in transit.
The conversion uses FFmpeg, the industry-standard multimedia framework on our servers, ensuring reliable and high-quality output.
Some quality loss occurs during transcoding between formats. The converter uses high-quality encoding settings to minimize this.
Embedded subtitle tracks may not transfer between all container formats. Hardcoded subtitles (burned into video) are always preserved.
Yes. The audio track is transcoded and included in the output WebM file.
The converter uses the standard codec for WebM: VP8/VP9/AV1.
Yes. The converter handles video of any resolution, including 4K and higher. Processing time increases with resolution.
Conversion time depends on file size and duration. Most files under 50 MB convert in seconds.
Currently, files are converted one at a time. Upload your next file after downloading the result.
Files up to 50 MB are supported for free conversion.
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