Puzzle Fuel is a daily puzzle site. This page explains what we collect, why we collect it, and how to have it removed. It covers puzzlefuel.com, the puzzle frames libraries embed on their own sites, and the Puzzle Fuel app inside ChatGPT.
Playing without an account
You can play every puzzle without signing up. When you do, your browser stores a random anonymous identifier (we call it pf-aid) plus your saved progress on each puzzle. The identifier is a random string. It is not derived from your email, your device, or anything about you, and it never leaves the games it is used for.
We use it for exactly one thing: keeping your streak, stats and half-finished grids attached to the right browser. Clearing your browser storage erases it, and you start fresh.
If you create an account
We store:
- Your email address — to sign you in by magic link or Google, and to send the daily reminder if you ask for it.
- An optional handle — only if you set one.
- Your play record — which puzzles you solved, when, how long you took, hints used, your fuel balance, and your progress through the University lessons.
- Session cookies — so you stay signed in.
We do not ask for your name, your address, your phone number, or any payment details, because the site does not need them. There is nothing to buy.
Analytics and advertising
The main site loads Google tags for analytics and advertising, which set their own cookies and are governed by Google's privacy policy. We also keep our own coarse server-side record of page views and in-game events (puzzle started, hint taken, puzzle solved) so we can tell which puzzles are too hard and which lessons people finish. Those records are tied to the anonymous play identifier, not to your name.
The library puzzle frames and the ChatGPT app carry no advertising and no analytics tags of any kind. That is a deliberate architectural split, not a setting.
Puzzles embedded on library websites
When a library embeds one of our puzzle frames, we record one line per frame load: which library, which game, and the address of the page holding the frame. That is how a library gets its usage numbers. We do not set cookies in those frames, we do not receive anything about the person playing, and we cannot see anything else on the library's page.
We send the daily reminder only if you turn it on, and every one carries a one-click unsubscribe. We send sign-in links when you request them, and occasional service notices about your account. We do not sell, rent or share your email address.
How long we keep things
Account data stays until you delete your account. Anonymous play records age out on their own as browsers clear storage. Server logs and event records are kept in a rolling window for operational and abuse-prevention purposes and are not used to build a profile of you.
Getting your data removed
If you have an account, you can delete it yourself from your account page. Deletion removes your email, your handle, your solve history, your stats and your fuel balance. It cannot be undone.
If you would rather not use the site to do it, or you want a copy of what we hold, ask us through our contact form and we will handle it.
Children
Puzzle Fuel is a general-audience puzzle site and is suitable for teenagers, but it is not directed at children under 13 and we do not knowingly collect information from them. If you believe a child under 13 has created an account, write to us and we will remove it.
Changes
If this policy changes in a way that affects what we collect, we will change the date at the top of this page. Material changes to account data handling will also be emailed to account holders.
Puzzle Fuel apps in ChatGPT
Our ChatGPT apps (Sudoku, and any others we publish) serve puzzles and explain solving techniques. They have no sign-in, set no cookies, and never receive your identity, your ChatGPT account, or your conversation. The board you are working on is held by ChatGPT on your device and sent to us only while a tool call is being answered.
Like any web service, our servers keep request logs when ChatGPT calls our puzzle tools: the time, which tool was called (for example “get today’s puzzle”), the requesting network address, and a client identifier string. We use these only for aggregate product statistics — how many boards were served each day, which games get played — and for abuse prevention. They are not linked to any account or profile, and we do not use them for advertising or tracking across services.
Some of our apps also report an anonymous completion event when you finish a puzzle on the board: which game and edition, how long the solve took, and how many hints or reveals were used. These events contain no identity of any kind — not even a network address — and exist solely so we can count finished puzzles. Logs and events are kept in the same way, and for the same periods, as the site statistics described above.
Contact
Questions about this policy go through our contact form, which reaches a person rather than a queue. You can also read who makes Puzzle Fuel.