Video Converter
Free online video converter. Convert between MP4, WebM, MKV and MOV right in your browser — pick an output format, nothing is uploaded.
What is the Video Converter?
The ByteTools Video Converter changes a video from one format to another — choose MP4, WebM, MKV or MOV as the output and the tool re-encodes your clip to match.
- Converts between MP4, WebM, MKV and MOV
- H.264 + AAC for MP4, MKV and MOV
- Open VP8 + Vorbis for WebM
- One tool for many format conversions
- 100% local — your video is never uploaded
- Free, unlimited and works offline once loaded
How to use the Video Converter
- 1
Drop a video onto the box or click to browse for one.
- 2
Choose your output format: MP4, WebM, MKV or MOV.
- 3
Click Convert and wait for the in-browser engine to finish.
- 4
Preview the converted video, then download it.
About the Video Converter
The ByteTools Video Converter changes a video from one format to another — choose MP4, WebM, MKV or MOV as the output and the tool re-encodes your clip to match. It is a single, flexible tool for making a video compatible with a particular device, editor, website or app.
MP4, MKV and MOV outputs use H.264 video with AAC audio for the broadest compatibility, while WebM uses open VP8 and Vorbis for the web. Whatever you pick, you get a clean file that plays where you need it.
All processing happens locally in your browser with a WebAssembly build of ffmpeg. Your video is never uploaded — no server, no account and no limits — so your files stay private and the tool works offline once it has loaded.
Frequently asked questions
How do I convert a video to another format?
Drop your video onto the tool, choose the output format you need (MP4, WebM, MKV or MOV), then click Convert. The engine re-encodes your clip and gives you the new file to preview and download in the browser.
Which output format should I choose?
Pick MP4 for the widest compatibility across devices and apps, WebM for open-format web video, and MKV or MOV when a specific editor or workflow requires them. All use safe, well-supported codecs.
Does converting between formats lose quality?
Any re-encode is technically lossy, but the default quality settings keep the result very close to the source for most viewers. You gain compatibility with only a small, usually unnoticeable change.
Is my video uploaded to convert it?
No. The conversion runs entirely in your browser with WebAssembly, so your video is processed on your own device and never uploaded. Your files stay private on your machine.
Why is conversion slow for large videos?
Encoding runs on your own CPU rather than a server, so short clips convert quickly but long or high-resolution videos take time — WebM in particular is slow. A modern desktop browser is recommended for large files.
Guides for Video Converter
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