About Thendal

Most online file tools work by uploading your file to a server, doing something to it, and sending it back. That works, but it means a copy of your file — your photo, your spreadsheet, your document — sits on someone else's computer, at least for a while.

Thendal is built the other way around. Modern browsers are powerful enough to do this work themselves, so every tool here runs entirely on your own device. Your file is opened, processed, and saved locally. Nothing is uploaded. You can prove it: open your browser's network inspector, or just turn on airplane mode — the tools still work.

That single design choice is also why the site is fast, why it works offline, and why it can stay free: there are no servers doing per-file work, so there is almost nothing to pay for.

How it stays free

Thendal is supported by display advertising (not enabled yet) and runs on inexpensive static hosting. To be clear and honest about it: the tools themselves never send your files anywhere, but the site — like most sites — uses analytics, and will use advertising, which involve cookies. Our privacy policy spells out exactly what that means.

Who runs Thendal

[Maintainer — replace this whole paragraph with a real, brief, first-person introduction. This is the most important part of the page for trust. Include: your name (or the name you publish under), one line on who you are or what you do, and why you built these tools. A single honest sentence like "I'm ___, a ___ who got tired of uploading private files to random converters, so I built ones that don't" beats any amount of polished filler. Reviewers and Google both look for a real human here.]

[Optional but recommended: a link to your GitHub, a personal site, or a professional profile — one real, external link is a strong trust signal. Once you add your name here, also add a founder Person to the Organization structured data at the top of this file.]

Got a tool you wish existed, or found a bug? Get in touch.