Privacy policy

playjustone.com is made and run by Atypical Makers. The controller of any personal data described here, in the sense of the GDPR, is:

Write to that address about anything on this page — it is the same inbox that answers a bug report.

Every puzzle is playable without signing in, and an anonymous game leaves nothing behind on our side that points at you. What the site remembers for you between visits, it remembers in your own browser — in local storage, under names that begin withjustone.: your finished games and your half-solved boards, the small choices you have made along the way — which rules cards you have closed, how you like a printed sheet, what you have folded out of the way — and the answers you have already given. Nothing there names or identifies you, none of it is sent to us or readable by us, and clearing your browser’s site data erases all of it for good.

Finished games build up there: your calendar and your streak are read straight out of them, so they stay in the browser until you clear it. Sign in later and this browser offers them to the account — but only what the account actually takes is removed here. Anything it cannot place stays exactly where it is.

The first time you open a game, its rules open with it. Your browser notes which games have already done that — game names, nothing more — so that no game introduces itself to you twice.

A day that went by unplayed can still be caught up, however long ago it was. Nothing new is written down for it: the board parks in your browser the way today’s does, with that day’s date on it, and finishing it makes an ordinary entry among your finished games, dated the day it belongs to.

Some moves are checked on the server — a Five letters guess has to be, or the answer would be sitting in the page. Those requests carry the guess, not you: nothing is written down and nothing is tied to a person.

A solved Nonogram asks you one question: did the picture look like anything? Answering adds one to a counter on that picture, and that is all of it — no account, no identifier, nothing that could be traced back to a person. The three counts are what tell us a drawing nobody can make out at 10 × 10, so that it stops being dealt at that size. It is one answer per picture, and the question is not asked again: which answer you gave is remembered in your own browser, so the board shows it back to you rather than asking twice.

A nonogram drawn in the editor is the address of its page — everything after the #. A browser keeps that part to itself: it is not sent with the page, so it never reaches our server, and the page views and events counted below stop before it — of a drawing they learn the size, never the picture. The board goes only where you send the link — and one somebody sent you stays in the address the same way. Where you got to on a board like that is kept in your browser as well, and nowhere else. An image you turn into a board is read by your browser alone and never uploaded.

Like any site, ours sits behind a web server — with traffic to it passing through bunny.net; both keep short-lived technical logs — the address a request came from, the path, the response — used to keep the site up and to look into faults or abuse, and rotated away shortly after.

An account exists so a streak survives a new phone. Everything an account holds is one of four things:

• Who you are. Your email address, which is what the account is known by. If you signed in with Google, also the name Google passed along — it is what the sidebar calls you, and its first letter is your avatar — and the address of your profile picture, never the picture itself, and as it stands nothing on the site displays it anyway. Signing in by email link keeps none of the rest: no name, no picture, just the address you asked us to write to.
• What you have chosen. The language you picked, the games you starred, which games have already introduced themselves to you, and a referral code — an unguessable string minted the first time you open the print page, so a QR code on paper never carries a database id. Settings and the names of games, kept on the account rather than in this browser so that a choice made on your phone is already made on your laptop.
• What you have done. The games you have finished, with the day, the levels, the board you ended with and the seconds of actual play it took; the pictures you draw and keep, each as the same code its link carries, with the name and credit you typed and whether you offered it for the daily pool; and the answers you give when a solved Nonogram asks whether the picture looked like anything.
• Where you got to. Boards you have not finished, so you can put one down on your phone and pick it up on your laptop, and how far through a set of them you are; and a summary of your play days — the first and the last, the run that last one closes, your longest ever — worked out afresh from your finished games each time one is recorded or deleted, so the streak beside your name does not have to count them all every time you open a page.

Those four are kinds rather than a list of fields, and deliberately so: the site keeps growing, and a list of fields would quietly stop being true. What is never in them is the part worth promising. Nothing about you beyond the address you signed in with and what Google passed along. Nothing bought, inferred, or told to us by anybody else. Nothing from another person’s account, and nothing at all about what you do elsewhere on the web. Anything that would not fit these four would be written here before it was ever kept.

Signing in with Google asks Google for your email address, your name and the address of your profile picture, and nothing more — we get no access to your Google account, and you can withdraw the connection at any time from your Google account settings.

The account also carries the day it was made, the day it last changed, and whether it has any extra role (a couple of accounts can curate puzzles). Sessions are kept in our database, and the cookie in your browser only points at one. The legal basis is Article 6(1)(b) — you asked for an account, and this is what it takes to give you one.

For a signed-in player, each game you finish leaves one row a day: which game, which day, when you finished, how many seconds of actual play it took, and the game’s own record of it — which levels are done, the board you ended with and, in Bridges and Star Battle, how many bridges you tore down or stars you took down along the way, so the archive can show it back to you.

A board you are still working on is kept separately so you can put it down and pick it up on another device; it is deleted the moment that board is finished.

If you answer the question a solved Nonogram asks — did the picture look like anything — we also keep which board you answered about and which of the three answers you picked. That much is tied to the account for one reason: so the same board on another device shows your answer back instead of counting a second one. Nobody else is shown it, nothing is scored on it, and it earns you nothing.

The seconds counted are active ones, and no clock is ever shown while you play. It is the history and the streak — the same ones a signed-out player already has in their own browser, kept somewhere a browser cannot reach — and it is used for nothing else. Legal basis: Article 6(1)(b) again.

The site sends exactly one kind of email: the sign-in link, when you ask for one. It is valid for fifteen minutes and it is the only thing that will ever arrive. There are no digests, no reminders, no “you haven’t played today”, and no marketing — the puzzle waits for you without being announced.

Delivery goes through Resend (Resend, Inc., United States), acting as our processor: they see your address and the message in order to hand it to your mail provider. That is a transfer outside the EEA, made under the European Commission’s standard contractual clauses.

We use Umami, an open-source analytics tool running on our own server rather than someone else’s. It sets no cookie, stores no IP address and builds no cross-site identifier, which is why this site has no consent banner: there is nothing here to consent to.

It records page views and, beside them, anonymous events about how the site is used. Each one is a short name for something that happened — a board started or finished, a share reached for, a sheet printed, the help opened, a link between our own pages followed — with at most a few plain facts the page has in front of it anyway: which game and which level, how the thing ended, the size of a board, where on the site it was done from, and the code a shared link or a printed sheet carried in. None of them carries anything about you. The list grows as the site does, but never in kind: an event is always a thing done on the page, never who did it. Legal basis: Article 6(1)(f), our legitimate interest in knowing whether anybody is playing.

All of them are first-party, all of them do a job you asked for, and none of them follow you anywhere:

• justone.locale — the language you picked. One year.
• justone.theme — light, dark, or whatever your system says. One year.
• justone.favourites — the games you have starred while signed out, so the star is already filled when the page arrives. Nothing but game names, and it is gone the moment you unstar the last one. Signing in moves them onto the account and clears this cookie. One year.
• authjs.session-token — your sign-in session, only once you sign in; it expires after thirty days, and signing out removes it immediately. Two short-lived companions (authjs.csrf-token and authjs.callback-url) exist only while you are signing in.

No advertising cookies, no analytics cookies, no third-party tracker of any kind.

A share or a printed sheet can carry a code — the link looks like https://playjust.one/p/sudoku/<code>, and it becomes an ordinary ?ref= parameter when it lands here. When a visit arrives with one, we note two things: the code, and the puzzle day. Not your address, not your account, not a device — there is nothing in that note to tie back to a person, and it exists to answer “did that sheet bring anyone at all”, never “who”.

The code on your own sheets belongs to your account, but it is random rather than derived from anything about you, so paper handed to a stranger gives nothing away.

The sheets on the printable pages are files made once a day and handed to everyone alike, so the code on those belongs to nobody: it names the game, the level and the day the sheet was made — pdf-sudoku-gentle-2026-08-26, say — and nothing else. A visit from one of them is noted the same way, and tells us only which sheet came back.

The site and its database run on servers of Hetzner Online GmbH in Nuremberg, Germany — inside the European Union.

Besides Hetzner, only three companies are involved at all:

• bunny.net (BunnyWay d.o.o., Slovenia — inside the EU) stands in front of the site and serves its pages: every request passes through its servers, so it sees what our web server sees — where it came from and which page it asks for. It also keeps copies of the pages that are the same for everyone close to you, so they open faster; nothing personal is in those copies;
• Resend delivers the sign-in email;
• Google, and only if you chose to sign in with Google.

Nobody else. Your data is not sold, not shared, not handed to an advertising network, and not used to train anything. We would disclose it only if the law actually required us to.

We may point you at something else we make — another of our sites, a thing we built. A link like that is a link and nothing more: nobody is paid for it, no network is told you followed it, and no profile of you is anywhere in it.

• Everything attached to your account — for as long as the account exists. Ask us to delete it and it all goes at the same time: the games, the pictures you kept, the sessions, the Google connection, all of it.
• A board you have not finished — until you finish it, then removed straight away.
• Something you keep on purpose — until you delete it, one at a time on its own page or all at once with the account.
• Counts that name nobody — the answers about a picture, the notes about shared links. They are kept as counts on the thing they are about, for as long as it is there. There is no one in them, so a deleted account does not empty them.
• Sign-in links — fifteen minutes. Sessions — thirty days.
• Server logs — days, not months.
• Whatever is in your own browser — until you clear it, or hand it to an account. It never reaches us on its own, so there is nothing here for us to delete.

You can ask for a copy of what we hold about you, ask us to correct it, ask us to delete it, ask us to restrict or stop processing it, or ask for it in a portable form. Write to contact@playjustone.com and we will answer within thirty days. There is no self-service delete button yet — a message is enough, and it gets done by hand.

You also have the right to complain to a supervisory authority. Ours is the President of the Personal Data Protection Office (Prezes Urzędu Ochrony Danych Osobowych), ul. Stawki 2, 00-193 Warsaw, Poland.

Nothing on this site profiles you or makes automated decisions about you, and the site is not built for children — it asks for no age because it has no reason to know one.

When this policy changes, the date at the top changes with it. If a change is a real one — a new processor, a new kind of data — it will be said plainly here rather than slipped into a sentence.