Utilore

Video Converter

Drop in a video, pick the format, and the conversion runs on your own machine. It is not instant — every frame is recomputed — but nothing is uploaded and there is no one else’s server to wait for.

or drop them here

MP4, MOV, MKV, AVI, WebM and more — up to 300 MB

    Converting video means recomputing every frame, and the engine runs on a single thread inside your browser — a minute of video takes minutes, not moments. In exchange, the file never leaves your device: no upload, no queue, no waiting for someone else’s server.

    How to use

    1. Drop a video onto the area below, or press «Select file» — up to 300 MB.
    2. Pick MP4 or WebM and choose the quality.
    3. Press «Convert», wait out the estimate, and download the result.

    Good to know

    Why it takes minutes, and why that is the honest trade

    Converting video means decoding every frame and encoding it again. The engine here is FFmpeg compiled to WebAssembly, running on a single thread inside the page — the multi-threaded build needs headers that would cut the site off from everything third-party. So a minute of video takes minutes. What you get for that wait is the thing an upload can never give: the file stays on your device. No queue, no size cap set by someone’s billing, no copy of your recording sitting on a server you have never heard of.

    MP4 or WebM, and quality that means what it says

    MP4 with H.264 plays everywhere — phones, TVs, editing software, ten-year-old laptops. WebM with VP9 is smaller at the same quality and is what the web itself prefers; it is also noticeably slower to encode here, and the estimate says so before you start. Quality is set as a constant rate factor rather than a bitrate: the picture holds and the size lands where it lands. A bitrate does the opposite — it holds the size and lets a busy scene fall apart.

    Frequently asked questions

    Is my video uploaded anywhere?

    No. The engine runs inside your browser, on your device. That is the point of doing it the slow way — a video you would not hand to a stranger can still go through a converter.

    It says my file is already MP4.

    Then converting it into MP4 again would cost quality and time and give nothing back. If you want a smaller file, change the quality; if you want a different container, pick WebM.

    Why 300 MB and not more?

    Because the whole file is held in memory while it is worked on, and beyond that a tab on a phone dies without an error message — which is worse than being told no in advance.

    The engine did not load.

    It is 30 MB, loaded once per visit and cached afterwards. On a weak connection the first load can fail; try again. Nothing else on the page needs it.

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