Privacy
Your 3D files never leave your device
Not as a policy commitment that could change, but as a property of how the site is built.
What happens to a file you add
Nothing leaves your computer. The file is read by JavaScript running in your own browser, converted there, and written back to a download that your browser creates locally. There is no upload, because this site has no endpoint that accepts one.
What is not collected
- File contents. Never read by anything outside your browser tab.
- File names, paths and sizes. Never sent anywhere.
- Model metadata: object names, material names, texture references, embedded author or application strings.
- Geometry metrics: triangle counts, vertex counts, dimensions, volumes, mesh health results.
- Which formats you convert between, or how many files you process.
- Accounts, because there are none. No sign-up, no email address, no profile.
What is collected
The site uses Vercel Analytics to count page views. It records the page URL, the referring page, and standard request information such as approximate location derived from IP, device type and browser. It runs from this same origin and sets no tracking cookie.
That is the entire list. It tells us that a converter page was visited. It cannot tell us anything about your model, because it is never given anything about your model.
How this is enforced
- No API routes, no server actions, no database, no object storage. There is no code that could receive a file.
- A Content Security Policy with connect-src set to this origin only. The browser blocks any attempt to send data elsewhere, whether from our code or from a compromised dependency.
- No third-party scripts, fonts, images or stylesheets. Every asset is served from this origin, so no other party even observes that you loaded the page.
- Automated browser tests that convert a real model while recording every network request, and fail if a cross-origin request appears.
- You can verify it yourself: open your browser devtools, switch to the network tab, convert a file, and watch what is sent. Or load the page, go offline, and keep working.
Local storage
One item is stored in your browser’s local storage: your light or dark theme preference, under the key mm-theme. It never leaves your device. Nothing else is persisted; your queue is gone when you close the tab.
Questions about the mechanism
How it works describes the architecture in detail: where the work runs, how memory is bounded, how untrusted archives are handled, and how every exported file is verified before you download it.