Convert files without uploading them
How to convert images, video and audio without sending them to anyone. A converter that runs in your browser, with no upload endpoint to send files to.
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What "no upload" actually means
Almost every file converter on the web works the same way. You choose a file, your browser sends it to a server, that server runs the conversion, and you download the result. The file leaves your machine, sits on somebody else’s disk, and you take their word for what happens to it next.
This site does not have that server. The conversion runs inside the page you are reading, on your own processor, using your own memory. The distinction is not a privacy policy or a promise about deletion — it is that there is no upload endpoint in the software at all.
How a browser can do this
Two things changed. Browsers gained real image and video decoders that JavaScript can reach directly, and WebAssembly made it possible to run FFmpeg — the same tool most conversion servers run — inside a tab at close to native speed.
So images use the codecs your browser already ships. Video and audio use FFmpeg compiled to WebAssembly, downloaded once and then cached. Neither path involves a network request carrying your file, because neither needs one.
What you give up
Being honest about the trade: your device does the work, so a long video takes longer on a phone than a server farm would take. There is no queue and no daily cap, but there is also no borrowed processor. For images and short clips the difference is imperceptible. For an hour of 4K footage it is real.
What you get in exchange is that the file never moves, there is no size limit, no account, and nothing to delete afterwards because nothing was ever stored.
Check it yourself
The claim is verifiable in about thirty seconds and you should not take it on trust. Open the developer tools in your browser, go to the Network tab, and convert a file. Watch what is requested. You will see the page, the stylesheet, the scripts, and on a video job the conversion engine. You will not see your file, because it never goes anywhere.
You can go further: load the page, turn off your Wi-Fi, and convert something anyway. It still works, which is only possible if the work was never happening elsewhere.
Questions
Can you convert a file without uploading it?
Yes. A modern browser can decode and re-encode images, video and audio on its own, using the same codecs it uses to play them. The file is read from your disk into the page, converted there, and written back. Nothing is sent anywhere at any point.
How do I know the file is not being uploaded?
Open your browser’s developer tools, switch to the Network tab, and convert something. You will see the page and the conversion engine load, and then nothing further. There is no request carrying your file because there is no endpoint to send it to.
Is there a file size limit if nothing is uploaded?
No fixed limit. Server converters cap uploads because bandwidth and storage cost them money. Here the only ceiling is your own machine’s memory, so a large video is slower on a phone than on a laptop but nothing is rejected for being too big.