Offcloud guide
WEBM to MP4 converter: make your videos play on any device
You recorded your screen or saved a video from the web, and now the WEBM file refuses to open on your phone, your TV, or your video editor. Offcloud converts WEBM to MP4 for free, directly in your browser: no signup, no watermark, and no file ever uploaded to a server.
Why convert a WEBM file to MP4?
WEBM is everywhere behind the scenes: screen recorders, browser recording tools, and many web downloads produce it by default. It is an open, efficient format that works beautifully inside Chrome or Firefox, which is exactly why so many recording apps choose it. The trouble starts the moment your video needs to live outside a browser tab.
iPhones and iPads will not play WEBM in their built-in video players, most smart TVs simply ignore the file, and editors such as iMovie refuse to import it. MP4, on the other hand, is the closest thing video has to a universal container: it plays on virtually every phone, TV, editor, and messaging app made in the last decade. Converting your WEBM to MP4 solves the compatibility problem once, for every device.
Nothing to upload: the conversion runs entirely in your browser
Offcloud works differently from most online converters. Thanks to WebAssembly, the entire WEBM to MP4 conversion happens on your own device: when you drop your file onto the page, no upload starts, because none is needed. The video is re-encoded locally, and nothing is stored online or kept once the conversion is done.
That matters more than usual for this format, because WEBM files are very often screen recordings, and screen recordings tend to show private things: work dashboards, chat windows, internal meetings. With Offcloud, that footage never touches a server, and there is no account to create and no library where your files could linger. Close the tab, and nothing remains online.
Quality, honest limits, and practical tips
Converting WEBM to MP4 means re-encoding the video, and Offcloud keeps the result as close to the original as possible. Be aware, though, that no converter can add detail that was not in the source: a slightly blurry screen capture will still be slightly blurry as an MP4. What you gain is compatibility, not extra sharpness.
There is no server-imposed size limit, since there is no server involved; the only real constraint is your device's memory, so a long recording simply takes more time to process. On modest hardware, closing a few heavy tabs before converting a large file helps things run smoothly. One last courtesy: please convert only videos you own or have the rights to use.
Conversion steps
- Open Offcloud in your browser and drag your WEBM file onto the page, or click to select it from your device.
- Choose MP4 as the output format for the conversion.
- Let the conversion run directly in your browser; your recording is never uploaded to any server.
- Download the finished MP4 and play it on any device, from iPhones to smart TVs.
Frequently asked questions
Why won't my WEBM video play on my iPhone or smart TV?
The native video players on iOS and on most TV platforms do not support WEBM, so the file is simply rejected or plays back with no picture. Converting it to MP4 gives those devices a format they are built to play.
Does converting WEBM to MP4 lower the video quality?
The conversion re-encodes the video, and Offcloud keeps the output as faithful to the source as possible. Keep in mind that no conversion can improve the original: your MP4 will look as good as the WEBM it came from, never better.
Is my screen recording uploaded to a server during the conversion?
No. The entire WEBM to MP4 conversion runs locally in your browser using WebAssembly, so your recording never leaves your device and nothing is stored online.
Can I convert a long WEBM screen recording, such as a one-hour capture?
Yes. Offcloud imposes no file-size limit of its own; the only constraint is your device's available memory. Very large recordings simply take longer to process.
Do I need an account or a paid plan to convert WEBM to MP4?
No. Offcloud is completely free, with no signup, no watermark, and no hidden paywall. You open the page, convert your file, and download the MP4.