Convert video formats
Phone MOV to MP4, screen-recording WebM to MP4. Uses your browser's hardware encoder, so it is faster than upload-based services and handles videos of several gigabytes.
Settings
How to use
- 1
Add videos
Drop MP4, MOV, WebM, MKV and similar files. Several videos can be converted in turn with the same settings.
- 2
Choose the output format
MP4 (H.264), WebM (VP9), MOV or MKV. When the codec already matches, the stream is copied instead of re-encoded, which is very fast.
- 3
Convert and save
Save once the progress bar reaches 100%. Long videos take a while; keep the tab open.
Codecs and containers
MP4, MOV and MKV are written with H.264; WebM with VP9. When the input codec already matches the output (e.g. an H.264 MOV to MP4), the streams are copied without re-encoding — no quality loss and only a few seconds.
When the codecs differ (e.g. a VP9 WebM to MP4), the video is re-encoded. Speed then depends on your hardware; devices with a hardware encoder process several to more than ten times faster than real time.
Frequently asked questions
Which browsers are supported?
Desktop Chrome, Edge, Safari 17+ and Firefox 130+. Video processing needs WebCodecs, and unsupported browsers see a notice on the page.
Is there a size or length limit?
None from the site. Processing streams the input so length is not an issue, but the output is held in memory before saving, so outputs larger than your device's memory (several GB) may fail.
Is quality lost?
Not when the codec matches, since the stream is copied. When re-encoding, the Quality setting applies; at "Very high" the difference is negligible.
Can it read H.265 (HEVC) video?
Yes, if your browser can decode HEVC. Safari, and Chrome / Edge on Windows and Mac machines with hardware decoders, usually can. Output is H.264 or VP9.
Help us improve the service
If a conversion fails, sending us the circumstances helps us track down the cause. Knowing which devices and formats fail most often, and how long processing takes, lets us revise the supported formats and fix the bugs behind them. If you don't mind, leaving this on is a real help.
What is sent
The tool you used and the settings you chose (output format, quality, etc.), your device specs (GPU, memory, core count), the input format with a rough size, how many files succeeded or failed and how long it took, and the error type and details when something fails.
What is never sent
The files themselves, file names, text, subtitles or prompts you add to a video, and IP addresses. The data goes only to this site's own server, never to a third-party service.