Privacy, in plain words.
BrainFitness needs no account and shows no ads at present. We measure visits with privacy-friendly analytics, and your game records stay in your browser.
Data in your browser
Your records live in this browser’s localStorage and are not tied to any account. bf_best_… and bf_streak keep workout personal bests and your daily streak. brainfitness:puzzles:v1 keeps puzzle progress (boards, completed levels, best moves, hint use and your Sand Blast best score), favorites and the sound setting. Queens saves its boards and settings under keys starting with star-battle-…, and Sand Blast remembers its performance mode in sandblast_performance_mode. The clear button on My progress removes bests, streaks and puzzle progress; clearing this site’s data in your browser removes everything. The games still work when storage is blocked.
Analytics and server logs
In production we run our own Plausible Analytics server. It sets no cookies and collects no personal data, only totals such as pages viewed, referrers, country and device type. When enabled, Microsoft Clarity and Google Analytics 4 also help us understand how pages are used. They may set cookies and record interactions such as clicks and scrolling, under Microsoft’s and Google’s own privacy policies. Our hosting provider may keep ordinary server logs, such as IP addresses, request paths and times.
Challenge links and sharing
To create a workout challenge link, the page sends the game and your score to our server, which returns a signed token and stores nothing. The link carries that token instead of a plain score, so the number cannot simply be edited. Puzzle links contain only the language, game, level and a referral marker, never a solution. Sharing to X, LINE or your device’s share sheet takes you to that platform under its own policies. If we add accounts or ads, we will update this page first.