Privacy

Updated October 18, 2026. This notice describes the Windrose calculator operated by the independent Sine Tools project.

Your calculator plan

Calculations run in your browser. Selected items and inventory are saved in your browser’s local storage so your plan can be restored. You can reset the plan in the tool, or remove the site’s stored data through your browser settings.

Feedback you submit

When you send feedback, we store its category, text, current calculator, selections and station-cost option, catalogue version, submission identifier, a random browser identifier, and submission time in our private database. The browser identifier helps limit spam. The form does not ask for your name or email.

We use feedback for product research, fixing recipes and bugs, and choosing features. We may export notes and calculator context for analysis using language model services. Exported feedback excludes the random browser identifier. Please leave personal, financial and confidential information out of your note.

Feedback is not published through the tool and is retained while used for product research and support. To request removal of a note, use the feedback form and identify the note with its approximate submission time and a short excerpt.

Traffic measurement and hosting

We use Vercel Web Analytics to understand visits, referral sources, pages used, and approximate device and geographic information. Page URLs sent by our integration exclude query strings and fragments. Optional usage events identify plan use, successful checklist copies, successful feedback submissions, and inventory maximum actions without sending feedback text, inventory or browser identifiers.

Vercel hosts the frontend, Render hosts the backend, and Supabase hosts our database. Hosting services process network requests and may maintain operational logs. Learn more about Vercel Analytics privacy.

Advertising

The calculator does not currently display ads or load Google advertising scripts. If advertising is enabled, we will update this notice and provide the required consent controls before loading those scripts.

Contact

Send project and privacy questions through the feedback form. There is currently no email reply channel through that form.