Free Video Converter — MP4, WebM, MOV, GIF
Convert videos between MP4, WebM, MOV, MKV, AVI and GIF — entirely in your browser. No account, no upload, no tracking. Trim, resize and compress before download.
Drop your video here
or choose a file from your device
Supports MP4, MOV, WebM, MKV, AVI, GIF and more
Every conversion runs entirely in your browser. Your video never leaves your device.
How it works
Three steps, no account, no upload. Conversion happens entirely in your browser.
Choose your video
Drop a video onto the page or pick one from your device. MP4, MOV, WebM, MKV, AVI and GIF are accepted.
Pick a format and quality
Select MP4, WebM or GIF. Tune the quality slider to balance file size and fidelity, and optionally trim or resize.
Convert and download
Press Convert. The video is encoded inside your browser by ffmpeg-wasm, then downloaded. Nothing is uploaded.
Popular conversions
Each link below opens the converter pre-tuned for that conversion.
Supported formats
MP4 is the safest default for web and mobile playback. WebM gives the smallest files for modern browsers. GIF is for short, soundless animations.
WMV, FLV and other legacy/streaming formats are not supported in this version. Please convert those to MP4 first using a desktop tool.
| Format | Input | Output | Notes |
|---|---|---|---|
| MP4 | Yes | Yes | H.264 + AAC, broadest compatibility |
| MOV | Yes | No | Apple/QuickTime container; convert to MP4 |
| WebM | Yes | Yes | VP9 + Opus, smaller than MP4 |
| MKV | Yes | No | Container; convert to MP4 or WebM |
| AVI | Yes | No | Legacy container; convert to MP4 |
| GIF | Yes | Yes | No audio, short clips only |
| WMV | No | No | Not supported |
| FLV | No | No | Not supported |
Frequently asked questions
Is this video converter free?
Yes. vexo is free to use, no account is required, and there are no paid plans.
Are my videos uploaded to a server?
No. vexo runs entirely in your browser using ffmpeg compiled to WebAssembly. Your videos are never uploaded, never seen by our infrastructure, and never stored anywhere outside your device. When you close the tab, every file is gone.
Which formats are supported?
Inputs: MP4, MOV, WebM, MKV, AVI, MPEG, 3GP, OGV and GIF. Outputs: MP4 (H.264 + AAC), WebM (VP9 + Opus) and animated GIF.
Why does the first conversion take a moment?
The first time you convert a video, vexo downloads the conversion engine (about 25 MB). After that it stays in your browser cache, and subsequent conversions start immediately.
Is there a file size limit?
Yes. Each file may be up to 200 MB. Browser memory is the real ceiling — very large 4K clips may struggle on lower-end devices.
Can I trim or resize the video?
Yes. You can set a start/end time to trim and pick a target width (1080p, 720p, 480p, 360p or original).
How long does a conversion take?
Depends on the video. A 1-minute 1080p MP4 typically converts in 1–3 minutes on a modern laptop. Mobile is slower. The progress bar shows real-time progress.
Why is my converted file bigger than the original?
If you raise the quality slider above the source's encoder settings, the output can grow. Lower the slider toward 50–70 for noticeable shrink, or trim/resize to drop the bitrate further.
Can I convert multiple videos at once?
Not yet. Video encoding is memory-heavy, so vexo converts one file at a time. Batch support may come later.
Are ads required to use the tool?
No. Ads are isolated from the converter. The tool works completely even if ads fail to load or are blocked.
Your videos never leave your device
vexo is a static page. Every conversion runs inside your browser via ffmpeg compiled to WebAssembly. There is no server-side processing, no upload, no temporary file, no cache. When you close this tab, every file is gone.
- No account required.
- No server processing. Your videos stay on your device.
- No caching, no Service Worker, no IndexedDB persistence.
- The conversion engine (ffmpeg-wasm) is fetched from a public CDN and cached by the browser; no personal data is sent.