Your files stay on your machine
This is not a policy about how carefully we store your data. It is a description of an architecture in which we never receive it.
How conversion works here
When you select a file, the browser reads it from your disk into memory and passes it to a Web Worker running in the same page. The worker parses the file, converts it, and hands back a result which becomes a download link. Every one of those steps happens on your device.
There is no upload request involved. You can verify this yourself: open your browser's developer tools, switch to the Network tab, and convert a file. You will see the page's own assets load and nothing else. You can also disconnect from the network entirely after the page has loaded — the converter keeps working.
What is never collected
- File contents, in whole or in part.
- File names.
- Column names, schemas, or any values from your data.
- Anything derived from your data beyond aggregate row and byte counts shown to you locally.
What is collected
Nothing. There is no analytics on this site — no Google Analytics, no Plausible, no Umami, no pixel, no counter of any kind. Not a reduced or privacy-friendly version of analytics: none at all.
That is a deliberate choice rather than an oversight. A converter whose entire promise is that your data stays on your machine has no business measuring what you do with it. The cost is real — we cannot see which formats people need next, and have to guess from search demand instead — and it is a cost worth paying.
The site is static files on a CDN. There is no server, no database, and nowhere for such data to be written even if we wanted it.
Advertising
The site carries ads, which are what keep it free. Ad networks set their own cookies and apply their own policies, and you can block them without losing any functionality here. Because your file never leaves the page's memory, no ad script has any path to your data. Read more about why the ads are here.
Local storage
Two keys are written to your browser's session storage, both of them flags so the page does not repeat itself: one records that the post-conversion message has been shown, the other that you dismissed the bottom ad bar. They hold nothing but a "1", they never leave your browser, and they clear when you close the tab.
No cookies are set by this site. If ads are running, the ad network sets its own — that is the one exception, and it is described above.
The one honest caveat
Everything above describes conversions performed by this site. If a future feature ever required server-side processing, it would be labelled as such on the page that offers it, and the claim on this page would be narrowed accordingly. Today, every conversion listed on this site runs locally.
