Privacy policy
Sudoku Arena · last updated 16 October 2026
Sudoku Arena is a Sudoku game with daily challenges, weekly tournaments, leaderboards and friends. This policy explains what we store, why, how advertising on the site works, and how to delete your data. We never sell your personal data.
What we store
- Account: your username, your password and the answer to your security question. The password and the answer are stored only as one-way encrypted hashes; nobody can read them, including us.
- Optional details you choose to add: an email address (only for password resets), a country, and an avatar choice.
- Game data: the puzzles you play, your moves and times, scores, mistakes, hints, streaks, achievements, tournament results and medals.
- Friends and online status: the friend requests you send and accept, and when you were last active, so friends can see whether you're online (you can hide this in Settings).
- Security logs: your IP address and device type are processed to prevent abuse (rate limits, cheating and account-takeover checks) and kept for at most 30 days.
What other players see
Your username, avatar, country (if you set one), scores, ranks, medals and public statistics appear on leaderboards and your profile. Friends can also see whether you're online and what level you're playing, unless you turn that off. Your email, password, security question and answer are never shown to anyone.
Why we use it
To run the game: to sign you in, verify scores fairly, rank tournaments, show leaderboards and friends leagues, and let you recover your account.
Advertising and cookies
The Sudoku Arena website shows ads from Google AdSense to keep the game free. We don't give Google your account details or game data. However:
- Third-party vendors, including Google, use cookies to serve ads based on your prior visits to this website or other websites.
- Google's use of advertising cookies enables it and its partners to serve ads to you based on your visits to this site and/or other sites on the Internet.
- You may opt out of personalised advertising by visiting Google's Ads Settings. You can also opt out of some third-party vendors' use of cookies for personalised advertising at aboutads.info.
- Google explains how it uses information from sites that use its services at policies.google.com/technologies/partner-sites.
Visitors in the European Economic Area, the United Kingdom and Switzerland are asked for consent before personalised ads or advertising cookies are used, through a consent message provided by Google. You can change your choice at any time from the "Privacy and cookie settings" link that message provides.
Rewarded ads ("watch an ad to continue") are always optional. Our own cookies and similar storage are used only to keep you signed in and remember your settings. The Android app currently shows no ads.
Where it is kept
On our game server and database, hosted by Render and Neon, with encrypted (HTTPS) connections. The website is delivered by Cloudflare. The app also keeps your settings and sign-in on your device.
How long
As long as your account exists. When you delete your account, your username, email, password, security question, avatar, country, friends and notifications are erased straight away. Past tournament results stay only as "deleted player", so that final standings remain correct. Security logs expire within 30 days.
Deleting your account
In the app: Settings → Account → Delete account. Other ways are described on the account deletion page.
Children
Sudoku Arena is not directed at children under 13, and we don't knowingly collect data from them.
Contact
Questions or requests: aykothavade@gmail.com. If this policy changes, the date at the top changes too.