Privacy

ChessReflex is run by Brody Kretz, an individual developer in Boulder, Colorado, USA. For anything about your data, email brody@chessreflex.com.

You can use ChessReflex without signing up. In that case:

• Your progress (courses, review history, ratings, settings, and any chess.com or Lichess username you enter) is stored in your browser's local storage, on your device only.
• We record anonymous usage events, such as which page you opened or that you finished a drill, with a random ID your browser makes up and keeps, plus the country your connection comes from. Your IP address is used briefly to stop abuse and is never stored. The ID is not linked to your name, email or account.
• Vercel Web Analytics counts page views, referring sites, country and device type. It uses no cookies and doesn't identify you.

If you sign up, we also store:

• Your email address, through Supabase Auth. With Google or Apple sign-in we receive your email from them (Apple may give us a private relay address instead); we never see those passwords.
• A copy of your training data, synced to our database so it follows you between devices. This includes any chess.com or Lichess username you entered.
• Sign-in cookies, which keep you logged in.
• If you joined through a friend's invite link: who invited you, a running count of how much you've used ChessReflex (to check the invite went to a real player), and a salted one-way hash of the network address you signed up from, used only to spot many accounts made by one person. The address itself is never stored. The invite link sets a cookie that remembers the invite until you sign up.
• If you invite friends: your invite code, how many joined, and any free Pro you earned.

• If you choose a public name, it appears on the leaderboard with your daily scores, and on any mini you publish. Until you choose one, the leaderboard shows a random handle instead.
• Minis you publish are public: anyone can play them, and their pages can appear in search results. You can delete them from the Mini page.

If you enter a chess.com or Lichess username, our server fetches that account's public games from chess.com or Lichess to build puzzles from them. The opening explorer and puzzle search send chess positions to Lichess, and nothing else about you.

The feedback form stores your message, the page you sent it from, your account ID if you're signed in, and an email address only if you choose to give one.

ChessReflex Pro is paid through Stripe on the website (and, once the iOS app is out, through Apple in the app). Card details go to them, never to us. We keep your Stripe customer ID and your subscription's status and renewal date, so we know whether your account has Pro.

ChessReflex shows no ads today, and no advertising scripts run on the site. If that changes, this page will say which ad network is used, and we'll ask for your consent wherever the law requires it before any ad loads.

The only cookies are Supabase's sign-in cookies, set when you have an account; they are needed to keep you signed in. Local storage holds your progress and the random analytics ID described above. There are no advertising or tracking cookies.

We don't sell your personal information or share it for advertising. We use these services to run ChessReflex, and they handle data only for that purpose:

• Supabase: database and sign-in
• Vercel: hosting, server logs and page-view analytics
• Stripe and Apple: payments
• Google and Apple: sign-in, if you choose them
• chess.com and Lichess: public game and opening data, as described above

These services are in the United States, so your data is processed there.

Account data stays until you delete your account. Deleting it removes your email, synced progress, public name, scores, published minis and subscription record. Anonymous usage events and feedback carry no contact details unless you added an email to feedback, and we keep them to understand how ChessReflex is used.

• Download your data or delete your account at any time in Settings. Deleting your account also cancels any Pro subscription bought on the website.
• Local data can be cleared from your browser settings.
• Depending on where you live (for example under the GDPR or California law), you can also ask us to access, correct or delete your data, or object to how we use it. Email brody@chessreflex.comand we'll answer within 30 days.

ChessReflex is not meant for children under 13, and we don't knowingly collect personal information from them. Accounts require you to be 13 or older. If you believe a child under 13 has an account, email us and we'll delete it.

If this policy changes, the date at the top changes with it, and a significant change will be announced on the site before it takes effect.