Calculator data
Measurements entered into calculators are processed in the browser and are not intentionally transmitted to Curtain Size Lab or saved to a user account. The multi-window project is stored in local browser storage only when you add or save a window; you can export it, import it, or delete the browser copy from the calculator.
Browser storage can be cleared and is not a dependable backup. Exported project files remain under your control. Do not use window names or notes for addresses or sensitive personal information.
Aggregate analytics
Cloudflare Web Analytics measures aggregate traffic without cookies and is not used by Curtain Size Lab to identify a visitor or follow them across websites. Cloudflare publishes its own current privacy and data-processing terms.
Curtain Size Lab also records anonymous page visits, landing and exit paths, scroll milestones, coarse active time, internal-link clicks, calculator starts and completions, project actions, print actions, and eventual monetization-link clicks in its own site database. A random identifier groups events only within the current browser session. A non-unique local flag reports whether this browser has visited before; no persistent visitor identifier is sent or shared with another Size Lab site. The database does not store entered dimensions, filenames, files, window names, project names, notes, full referrer URLs, or IP addresses. Global Privacy Control or Do Not Track disables this collection. Event records are deleted after about 400 days.
If you choose Allow Google Analytics, Google Analytics measures page visits, the first interaction with a calculator, and successful project actions such as saves, exports, print requests, and validated imports. Curtain Size Lab does not send entered measurements, files, filenames, window names, project names, or notes. Advertising and personalization signals are disabled.
Technical delivery
OpenAI Sites hosts the application and Cloudflare provides domain, security, delivery, and analytics services. Those providers may process ordinary technical request information such as IP address, timestamp, requested page, and user agent to operate and protect their services.
Future changes
Advertising, active affiliate tracking, or lead generation will require a policy update and appropriate user controls before activation.