Cookies and browser storage

The stacker stores nothing about your frames; it keeps copies of the site's own pages for offline use. Measurement sets no cookie. Advertising, when switched on, may — after you choose, and the choice itself is the one value this site keeps.

What the site itself stores

One thing at most: where consent is required and you have answered the advertising question, the answer is kept in this browser's local storage under sf-consent so the bar does not return on every page. Use Privacy choices in the footer to clear that answer and choose again. And, so the stacker opens without a network, copies of the site's own pages and scripts (never a frame) in the browser's cache storage, kept by a service worker that always asks the network first. When you are not signed in, nothing else — no cookie, no IndexedDB. Signing in adds the cookies below and two short-lived session-storage values during the sign-in itself. Frames, intermediate results and the finished image live in this tab's memory and are gone when it closes.

If you sign in

Three cookies, only when you use the optional account: __Host-sf-focusstack (the session, HttpOnly, 12 hours), __Host-sf-focusstack-hint (a flag with no content, so pages know to ask whether you are signed in) and __Host-sf-focusstack-state (ten minutes, during a sign-in). Signing out removes the first two.

Measurement

The cookieless Umami script sets no cookie and stores no identifier. It honours Do Not Track.

Advertising

Advertising surfaces are reserved on the guide pages and below a finished result, and their unit identifiers are currently empty, so no advertising library is requested and no advertising cookie is set. When advertising is switched on it will be Google AdSense; Google and its partners may then use cookies and similar storage for ad selection, delivery, security and measurement. Where consent is required, a Google-certified consent platform asks first, with reject as prominent as accept, and nothing loads until you answer. Declining leaves the stacker and the calculator fully usable.

Your choices

Your browser's own controls block or delete cookies for this site. The consent choice, where it appears, can be changed from the same bar on any page.

Last updated 15 September 2026. Questions: support@focusstacks.com