Privacy, simply.

What stays on your device

Your personal best, completed rounds, daily records, and sound preference are saved in local storage under “stack-one-v1”. Up to 90 daily records are kept. These values are not sent to a game server. They remain until replaced or removed; if storage is blocked, the game works but records may last only for the current visit.

Your light or dark appearance preference is stored separately under “stack-one-theme” and is not sent to a server. Until you choose a theme, the site follows your device's appearance setting. Resetting game records does not change your theme; clearing this site's browser data removes the saved preference. If storage is blocked, the toggle still works for the current page.

What you choose to share

A challenge URL contains your score, mode, and, for a daily challenge, its date. Anyone with the link can read those values. Result images are generated locally. Using a platform's share sheet or posting a link sends the information you choose to that service, whose privacy policy applies. Scores are not verified by a server.

Hosting and request information

The hosting provider may process IP addresses, browser details, timestamps, referring pages, and requested URLs in access and security logs to deliver and protect the site. Shared challenge values can appear in those URLs. Log retention depends on the hosting configuration and provider; it is separate from your local game records.

Contact messages

If you email the site, the recipient and email providers process your email address, message, and attachments to respond to your request. Do not send sensitive information. Correspondence may be retained as needed to handle the enquiry, security issues, or legal obligations. You can request deletion through Contact, subject to applicable retention requirements.

Google Analytics

We use Google Analytics 4 (measurement ID G-L76GSECFYN) to measure visits and understand how the site is used. The Google tag loads on each page and may use analytics cookies such as “_ga” to distinguish browsers and sessions. Google may receive page URLs and titles, referring URLs, browser and device details, and usage events. Challenge scores, modes, and dates in page URLs may therefore be included; the site does not explicitly upload your saved game records or email messages to Analytics.

Google processes this information under its Privacy Policy. Retention and additional measurement features depend on the Analytics property settings. You can block analytics scripts or cookies through your browser or use Google's Analytics opt-out browser add-on where supported. Blocking Analytics does not prevent you from playing. This version does not provide an on-site analytics consent selector.

Google AdSense and advertising cookies

The site loads the Google AdSense Auto ads script. Ad availability and placement depend on Google's approval, account settings, and other eligibility requirements. Google and its partners may use cookies, device identifiers, IP addresses, page URLs, and interaction data for ad delivery, measurement, fraud prevention, and, where permitted, personalisation based on visits to this and other sites. Advertising and analytics cookies are separate from the local storage used for game functionality.

This build does not include a custom advertising consent selector. Consent messages and choices, when configured by the site operator, are managed through Google's Privacy & messaging or another consent platform. Personalised advertising in the EEA, UK, and Switzerland requires a Google-certified consent platform integrated with the IAB TCF. This disclosure is not a substitute for any consent required before advertising or analytics collection.

Learn how Google uses information from partner sites and manage Google preferences through My Ad Center. You can also manage or block cookies and third-party scripts in your browser; blocking ads does not prevent you from playing. Those settings do not replace any consent choices required on this site.

Your choices and rights

Use Reset records to clear scores and round counts (it keeps your sound preference), or clear this site's browser data to remove all local preferences. Sharing and sound are optional. Depending on your location, you may have rights to access, correct, delete, restrict, or object to processing of your personal information, and to complain to a data-protection authority. Contact the site to make a request; local scores cannot be remotely looked up.

Children and changes

The site does not ask players for names, ages, or account details and does not knowingly solicit children's personal information. A parent or guardian concerned about information sent by email can contact the site. New services or advertising will require this policy to be reviewed. The date above identifies the latest policy update.