Ruthen Systems
Legal

Privacy policy

Plain-language policy, written and maintained by the site operator and checked against what the site actually does on 2026-09-15. It has not been reviewed by a lawyer.

The short version

  • The calculators run entirely in your browser. The dimensions you type are never sent anywhere.
  • There are no accounts, no logins and no marketing cookies.
  • No third-party analytics or advertising service is used on this site.
  • Anonymous usage events go to this site's own server only — no cookies, no identifiers.
  • The only personal data collected is what you type into the contact form.

The calculators

Every calculation and every DXF file is produced by JavaScript running on your own device. Your dimensions are not transmitted to the server, not stored, and not logged. If you close the tab, nothing is kept.

The contact form

When you send a message, the following is stored on a private server:

  • Your email address (required, so a reply can be sent).
  • Your name, if you chose to give one.
  • Your message.
  • The optional project details, if you filled them in: company, software in use, how often the job repeats and how long it takes, what causes errors, whether written rules and examples exist, and whether a licensed engineer approves the output.
  • Any file you attached (PDF, DXF, PNG or JPG, up to 10 MB).
  • The time of submission, your IP address and your browser's user-agent string.

The IP address and user-agent are kept for abuse prevention and rate limiting. They are not used to build a profile of you.

Purpose: to reply to your enquiry and, if it becomes a project, to carry out that work. Your details are not sold, rented or used for marketing lists.

Attachments

Files are stored on a private server outside the public web directory, under a randomly generated filename, and are never published or served to anyone. The original filename is recorded as text only.

How long any of this is kept

90 days. After that, an automatic daily job deletes the whole submission — your message, your name and email address, the recorded IP address and user-agent, and any attached file. This is a real scheduled deletion, not a policy someone has to remember to apply.

The exception is the one you would expect: if your enquiry becomes a project, the record is marked to be kept for as long as the work requires. That mark is applied by hand, by us, and nothing you send can set it.

You can ask for your message and any file to be deleted sooner, at any time.

Analytics

The site records anonymous interaction events — a page being opened, a tool calculation completing, a DXF being downloaded, a contact-form step being expanded — to understand which pages and tools are actually useful. Each event is sent to this site's own server and appended to a daily log. An event carries the event name, the page path, a coarse device class (phone, tablet or desktop) and the time. It carries no cookie, no identifier, no IP address and no user-agent string, so events cannot be linked to a person or to each other across visits.

Event logs are deleted automatically after 400 days. No third-party analytics provider is involved, so no consent banner is needed and none is shown.

Cookies

This site sets no cookies. Nothing here needs one: there are no accounts and no cross-site tracking.

Hosting and access

The site runs on a privately operated server and is delivered through Cloudflare, which terminates the connection and passes requests to the server. Cloudflare's own handling of connection data is governed by its privacy policy. The site's own server keeps the contact records described above and the anonymous event logs; the application does not keep a per-request access log. Access is limited to the site operator.

Your choices

You can ask, at any time, to:

  • see what has been stored about you;
  • correct it;
  • have it and any attachment deleted.

Use the contact form and say what you would like done. Requests are handled without argument.

Confidentiality of what you send

Drawings, dimensions and business information you send are treated as confidential. Nothing is published as a case study, example or screenshot without your separate, explicit, written permission — see how work is documented.

Last updated: 15 September 2026.