Chess Methodica uses account information, email, password hashes or linked Google identity, language and timezone settings to provide sign-in and training. Linked chess usernames identify public profiles; linking does not give us your chess-platform password.
We store imported public game metadata and moves, analysis results, archived games, puzzle attempts, training progress, review and mastery state, lessons, opening practice, and estimated ratings. Paid subscriptions add provider customer and subscription identifiers, status, dates and webhook fingerprints. Payment card details are handled by Dodo Payments / Lemon Squeezy, not stored by Chess Methodica.
Essential cookies support sign-in, language and Google sign-in state. Browser storage saves puzzle progress and interface preferences. Application code does not install advertising trackers. Hosting access logs may contain IP addresses and request information; these support operation and abuse prevention.
Google processes Google sign-in; Chess.com and Lichess supply linked public profile/game data; Dodo Payments / Lemon Squeezy processes checkout and billing. Hosting and email providers process data needed to operate the service. Their own privacy terms also apply. Cloud analysis sends selected game moves to our analysis service.
Training history is retained while your account is used; this release does not automatically erase inactive accounts. Contact support to request access, correction, export or deletion. Requests require identity verification. Billing records may need to be retained for applicable obligations, and backup copies follow the operator’s retention schedule.