The free tool you googled for is often ad-funded, and some of them harvest the very files you upload — a risk real enough that law-enforcement agencies have warned about it. We took the opposite path: make the trust claim physically testable.
The code comes to you
Client-side tools download their code once and then run on your device. Your files and figures never leave the browser; the tools make zero third-party network requests — no ads, no fingerprinting, no upload path at all.
Verify it yourself
You don't have to trust us. Whitelist the site, open your browser's developer tools, and watch the network tab stay silent — or just turn off your internet and watch the tools keep working. That's the Airplane Mode Dare.
Honest about what runs where
Of 353 tools, 307 run entirely in your browser; the rest are clearly labelled as server-side or bring-your-own-key cloud. No tool is implied to be private when it isn't.
Explore the tools, or take the airplane test and see for yourself.