How it works: your files never leave your device
Most online converters upload your file to a server. OnDevice tools do the work inside your own browser instead. Here is what that means, and how to check it yourself.
Upload-based converters compared with OnDevice Tools
Your file is copied to someone else's computer. You have to trust how they store it, who can see it and when they delete it.
Only the website comes to you. Your file (the green dot) is opened, converted and saved inside your device. It never travels.
What happens when you use a tool
The page loads
Your browser downloads the tool from our site, like any web page. This is the only thing our server sends.
You add a file
Your browser opens the file from your device. It is kept in memory and not sent anywhere.
Your device converts it
The tool runs in a background thread of your browser and saves the result as a download on your device.
Check it yourself in one minute
You do not have to take our word for it. Every browser can show you each request a page makes.
- On a computer, open any tool page in Chrome, Edge or Firefox.
- Press
F12(or right-click and choose Inspect), then open the Network tab. - Add a file to the tool and change some settings.
- Look at the list: you will see no request that carries your file. The page only loads its own small files from our domain.
Or try it offline: open the site once, turn off Wi-Fi and mobile data, and reload. The pages still open, because they are saved on your device. A website that needs to upload your file cannot work like that.
Our site also sends a strict security rule (a Content Security Policy) that tells your browser to block any attempt to send data to another website. Even a bug could not quietly upload your file somewhere else.
What we store
- Your files: nothing. They never reach us.
- Cookies: none. We do not use cookies or trackers.
- On your device: your theme choice (light, dark or auto), plus recent tool links only if you opt in through search. You can clear and turn off that history at any time. Your files and text are never saved there.
- Our server: no access logs. Our hosting provider handles basic technical data to deliver the site, as explained in our privacy policy.
- No uploads
- No sign-up
- No cookies or trackers
- Works offline
Questions
If nothing is uploaded, what does your server do?
It only sends the website itself: the pages, styles, fonts and the code for each tool. After that, the work happens in your browser.
Do you see the names of my files?
No. File names, sizes and contents stay in your browser. Nothing about your files is sent to us.
Is it slower than an upload-based converter?
Usually it is faster, because there is no upload or download wait. Very large files depend on the speed and memory of your device.
Why can a browser convert files at all?
Modern browsers can run fast code, including WebAssembly, in background threads called Web Workers. That is enough to read and write images and PDFs.