Privacy Policy

Last updated: November 2, 2026

Your files stay on your device

The 3MF to STL converter and the cost calculator run inside your browser. The contents of your files, their names and the model data in them are processed on your device and are never sent to our servers or to anyone else. We do not put file names in page titles, web addresses or usage events.

No accounts and no cookies of our own

You do not need an account. This site does not set its own cookies. The cost calculator remembers your settings (filament prices and densities, electricity price, printer power, machine wear, failure rate, markup, currency and filament diameter) in your browser’s local storage so you do not have to enter them again. They never leave your device, and “Restore defaults” removes them.

Usage events

To learn whether the tools work, the site sends short usage events to our server, such as “a file was selected”, “conversion finished” or “a cost was calculated”. An event contains only:

• the event type and which tool it came from;
• random identifiers created for this visit and for one use of a tool (they are not linked to you and are gone when you reload the page);
• device type (desktop or mobile), browser family and the site version;
• coarse facts about the task, for example a file size range, the number of plates, an error code, the download method, or the material and weight source chosen in the calculator.

Events never contain file contents, file or object names, free text, your IP address or your browser’s full user-agent string. We keep them for 180 days and then delete them. They are stored in Cloudflare D1.

Service providers

The site is hosted on Cloudflare. To deliver pages, Cloudflare processes each request, including your IP address, as described in the Cloudflare Privacy Policy. We use Cloudflare Web Analytics to count page views; it does not use cookies. Whether and how long Cloudflare keeps request logs is governed by its own policy, not by us.

Advertising

The site shows no ads today. If we add advertising later, we will update this policy before doing so, including any cookies and consent choices that come with it.

Children

The site is not directed at children under 13 and we do not knowingly collect personal information from them.

Changes and contact

We will post changes to this policy on this page with a new date. Questions: contact@3mftools.com.