MP4 to WebM converter.
Convert MP4 to WebM (VP9) for smaller, royalty-free files that load fast on the web.
Drop a video here or click to browse
MP4, MOV, MKV, WebM · processed privately, never uploaded
WebM (VP9) is the format built for the web: smaller than MP4 at the same quality and royalty-free, so it's ideal for background videos, hero clips, and anything you host yourself. Converting happens entirely on your device.
Why WebM for the web
VP9 inside a WebM container typically produces files 20 to 40 percent smaller than H.264 MP4 at matching visual quality, which means faster page loads and less bandwidth. It's royalty-free and supported by every modern browser (Chrome, Firefox, Edge, and recent Safari). For a background loop, a product demo, or a hero video on a site you control, WebM is usually the better choice.
When to stay on MP4 instead
WebM's tradeoff is reach. Older devices, some smart TVs, native mobile galleries, and editing software may not open it. If your video needs to play in PowerPoint, on an old phone, or drop into a legacy editor, keep MP4. Use WebM specifically when you control the playback environment, most often a webpage viewed in a current browser.
Getting the smallest usable file
Cap the resolution to what your layout actually displays: a background clip shown at 1280px wide doesn't need a 4K source. Combined with WebM's efficiency, downscaling to 1080p or 720p can shrink a hero video several times over. Keep quality Balanced for web backgrounds where perfect fidelity isn't essential; the smaller file usually matters more than the last few percent of sharpness.
Tips
- Use WebM for site background loops and hero videos, smaller files, faster loads.
- Keep MP4 if the video must play on old devices, TVs, or in PowerPoint.
- Downscale to the width your page actually shows; a background clip rarely needs 4K.
- Balanced quality is fine for most web video where load speed beats perfect fidelity.
How it works
- 01
Drop your MP4
Select the .mp4 file, it stays on your device, nothing is uploaded.
- 02
Choose quality
Cap resolution if you want a smaller file; Balanced is a good default.
- 03
Download WebM
Get a compact .webm for web pages and modern browsers.
Questions
- Is WebM really smaller than MP4?
- Usually yes, VP9 in WebM often lands 20 to 40 percent smaller than H.264 MP4 at the same visual quality, which is why it's popular for the web.
- Will WebM play everywhere?
- It plays in every modern browser, but not on some older devices, TVs, native galleries, or legacy editors. Keep MP4 if you need that broad reach.
- What's the best use for WebM?
- Video you host and control, website backgrounds, hero clips, and demos viewed in current browsers, where smaller size and faster loading matter.
- Is my MP4 uploaded anywhere?
- No. Conversion runs entirely on your device, no upload, no account, no watermark.