Convert to MP4

How to use Convert to MP4

1. Upload your video (AVI, MKV, MOV, WebM, MP4, and more).
2. Choose target resolution (keep source, 4K, 1080p, 720p, etc.).
3. Pick a quality level and target bitrate.
4. Click "Convert to MP4" and download the result.

What converting to MP4 buys you

MP4 with H.264 video is the most broadly compatible video format there is — it plays on essentially every phone, browser, TV, and editing application without extra codecs. Converting to it is usually about compatibility rather than quality or size.

Output is written with the metadata index at the front of the file, so it starts playing before it has fully downloaded rather than requiring the whole file first. That matters if you are uploading the result somewhere it will be streamed.

Choosing a resolution

Keep source is the right default when you only need format compatibility. Downscaling to 1080p or 720p is what actually reduces file size meaningfully, and for footage that will be watched on a phone, 720p is often indistinguishable from 1080p at a fraction of the size.

Upscaling a low-resolution source to 4K only makes the file larger. The detail is not there to recover.

Questions

Why is conversion slow compared to a desktop app?

Encoding runs in your browser through WebAssembly on a single thread, which is inherently slower than a native multi-threaded encoder. The trade is that your video is never uploaded anywhere.

Will converting improve quality?

No. Re-encoding can only preserve or lose detail, never add it. Convert for compatibility or smaller size, not to improve a low-quality source.