Privacy Policy

1. Information I Collect & How It's Handled

When you use the calculator engines for scale conversion, everything runs locally on your machine. Your STL scale data never leaves your browser.

Feedback Forms (Anonymous): If you drop a scaling issue, feature request, or update suggestion using the two feedback forms on this site (on the homepage and the reference page), that information is sent to a spreadsheet on Google Sheets and backed up on my secure, two-factor authenticated Google Drive. These forms are set up so they do not collect or store any names, email addresses, or personal information. I keep this raw community input around only for the duration of processing and adjusting the conversion numbers, after which it is deleted.

Contact Form (Google Form): The Contact page has a "Send me a message" button. Clicking "Open form" takes you off this siteto a Google Form I set up for replies. That form collects yourname, your email address, and the content of your message, so I know who wrote it and can write back. Your response is stored on myGoogle Drive (protected by two-factor authentication). I keep itonly for the duration of our conversation — while we sort out your question or issue. As soon as the matter is resolved and we're both satisfied, your name, email address, and message are permanently deleted.

Direct Emails: If you choose to send me a direct email, your name and the text within your message will land on my email host's secure servers at Proton Mail in Switzerland. Because I run this project entirely alone, I am the only person who will ever see or read your message. I keep your email active strictly while looking into your query or scaling issue. As soon as the matter is completely resolved, your email and its contents are permanently deleted.

2. The Web Observer — Exactly What It Stores

The only analytics on this site is a small custom web observer script — an anonymous, cookie-free visitor counter writing non-personal details to a private Google Sheet I can open. Imagine a click-counter at a shop door: it counts people coming in and notes roughly how they arrived, and nothing more. It does not store your name, email, IP address, or anything that can be used to identify you.

When a visit happens, the observer sends a few non-personal details to a Google Apps Script (a small program running in Google's cloud), which writes them into a Google Sheet that only I can open. Like Cloudflare, the Google servers that run this script briefly see standard network data — such as your IP address — purely to deliver the request to their cloud; none of it is stored in my sheet. The exact fields stored are:

In plain words, that means:

• Which page you viewed (page); how far down you scrolled is recorded on a rolling basis as you read, and stays empty on pages you don't scroll (scroll_depth).
• Where you came from — the site that brought you here, reduced to its address and page path with any tracking parameters removed, plus a coarse label for how you arrived (referrer, traffic_source: direct, search, social, or referral; engine: which search engine, when it was a search engine; ai_source: which AI assistant, when a link came from one).
• Broad device info — phone, tablet, or desktop, approximate screen size, browser family, and a coarse operating system label (device, viewport, browser, os).
• Whether the visit looks like a person — a plain label (agent: human, crawler, or automation) used only to keep search-engine and AI crawlers out of the human visitor numbers.
• Timestamps so I can see when visits happen (timestamp_utc, received_utc, date, time).
• What happened — normally a page view, or the scroll reading above (event, event_value).

There is no persistent visitor ID and no session ID: nothing is stored on your device to tell one visit from another, so the observer can't recognise you on a return trip. None of these fields can be used to work out who you are, and I never sell or share them. I use them for a single purpose: to understand which pages are useful so I can spend my time improving the right things. The full explanation also lives on the Legal page.

3. Cookies and Storage

STLACCESS sets no cookies, and the web observer stores nothing on your device — no persistent ID, no session ID, no tracking of any kind. The only browser storage the site can write is:

• Dismissal memory: if a site announcement or the feedback prompt is shown and you close it, a small flag in LocalStorage remembers that so it doesn't nag you again. It holds a timestamp and a "dismissed" marker — never any personal data — and clearing your browser's site data removes it.
• Observer opt-out: if you append?admin=1 to any page, a flag in LocalStorage keeps the web observer switched off for your browser. It stores only your own choice to be excluded.

Neither of these is used to measure you, and both can be removed at any time by clearing this site's data in your browser.

4. Your Data Control

Because I don't keep your personal information on any server database, you have complete control over your history:

• Wiping Info: You can clear anything this site has stored at any time by wiping your browser's site data for stlaccess.com.
• Turning off the observer: Visit any page with?admin=1 appended to the address (for example/3d-math?admin=1) and the web observer switches off permanently for your browser — no page views or scroll activity will be recorded from it again. You can switch it back on at any time by clearing your browser's site data.

5. Service Providers

I use a couple of trusted systems to keep the site functional:

• Cloudflare: The site is built and hosted on Cloudflare Pages. Cloudflare runs a worldwide network of servers that deliver pages quickly and protect the site from attacks. Because your requests travel through Cloudflare's servers, Cloudflare may see technical data that is outside my control — such as your IP address, browser, and the pages you request — so it can route and secure traffic. That data is handled under Cloudflare's own privacy policy, and I never see or store it. Cloudflare also keeps its own service and build logs for its network.
• Web observer + Google Sheets: The anonymous visitor counter sends non-personal visit details to a Google Apps Script, which writes them into a Google Sheet on a two-factor-protected Google Drive. No personal data, cookies, or IP addresses are stored.
• Google Forms + Google Drive: Responses to the contact form on the Contact page — your name, email address, and message content — are stored on my two-factor-protected Google Drive only for the duration of the conversation, then permanently deleted.
• Google Workspace & Proton Mail: For parsing anonymous form reports and reading direct support requests securely.

6. Affiliate Links & Advertising Disclosure

Right now: none. STLACCESS currently runs no ads, no affiliate links, and no sponsored banners. The calculators and guides earn nothing today — there is no ad network, no tracking pixel, and no paywall, and I intend to keep it that way.

If that ever changes: any sponsored placement or affiliate link that appears here will be clearly labeled as sponsored before you click it, will open in a new tab with rel="sponsored" attributes so search engines do not treat it as an editorial endorsement, and will never sit inside the calculators themselves. I will only link to offers that genuinely make sense for 3D printing and tabletop hobbyists.

When you click any outbound link — sponsored or not — the destination site may briefly see standard network data such as your IP address and browser, the same way every website works. I do not control what third parties collect on their own sites, and no link on this site sets cookies or collects personal data through STLACCESS. Any advertiser or affiliate partner has their own privacy policy, which I recommend reviewing before completing a purchase or offer.

Support page tips: donations on the Support page are direct wallet-to-wallet transfers (Bitcoin or Lightning). No form, no account, no email — nothing about you or your visit reaches me beyond what a normal blockchain transaction shows publicly.

7. Children's Privacy

STLACCESS is a general hobby site for 3D printing and tabletop gaming, and it is not directed at children under 13. Because there are no accounts, no profiles, no chat, and no file uploads, and because the calculators collect no personal information, there is simply nothing here that requires a child to hand over data — and nothing that needs an ID or age check.

• No personal data from kids: I do not knowingly collect personal information from children. The tools run entirely in your browser, and the web observer stores only the anonymous fields listed above.
• Under 13: This site is not made for children under 13. If you're under 13, please use it with a parent or guardian, and don't send me any personal details through the forms or email.
• Parents & guardians: If you believe your child has sent me a message containing personal details, just email me and I will delete it immediately.
• Worldwide age rules: Different countries set the minimum age for using online services differently (in the EU and UK it's typically 13 to 16). I follow the spirit of these rules: no personal data is collected from anyone, children included, so there is nothing to gate or verify. If your country requires parental permission for you to use a site like this, please get it first.

8. Drop Me a Line

If you have an issue with privacy setups or want to check how an edge layout works, feel free to open a ticket directly on the GitHub repository. For generic use rules, check out the Terms of Service.