Privacy

What is kept in your browser

LaviChess keeps a few small things in your browser's local storage (localStorage). They stay on your device, with two exceptions: when you play or watch online, your player name and the random id in sd:online:device go to our game server (only the id, when you react to or share a game); and if you have a profile, your games, your progress and your game settings are kept with it (see below).

The keys start with sd for Schackdags, LaviChess's Swedish sister: the two sites share their code. Your browser also keeps the site's files and the computer's chess program in its cache, and a service worker lets you play without a connection after your first visit, and shows your notifications if you've turned them on.

Statistics

We count visits with our own Umami, without cookies and without recognizing you from one visit to the next. Besides page views, these events are sent, with nothing that points to you:

The chess engine runs on your device

The computer that plays runs in your own browser, and so does the one on the analysis board. The games you play or paste in are not sent to us. (A game or position opened through a link is in the link's address, which the web server's log keeps for 14 days: see below.)

In the explorer on the analysis board, the Played here tab asks our server which moves have been played in the position on the board. It sends a code for the position, not the game, and the server answers with only the moves, game counts and results: no names, no games. The code is in the address, which the web server's log keeps for 14 days, like every address. The club players' numbers in the explorer come as files from our own server: your browser asks Lichess nothing.

Games you import from Chess.com and Lichess

On My games you can import your games from Chess.com or Lichess, and that only happens when you ask. Your browser then asks the site directly, with the username you typed, and gets your public games: the same games anyone can see there. The request doesn't go through us, and we get no password and nothing else from your account. Chess.com and Lichess see the request like any other visit to their site: your IP address, the username you asked about and that the request comes from LaviChess, but not which page, and not who you're logged in as there.

The games are kept only in your browser (sd:hamtade:v1), with the players' names as the site has them. The username is kept there too, so you can fetch new games next time (sd:hamta:v1). None of it is kept on our server or with your profile, and the computer that goes through the games runs here in your browser. A PGN file you add is read only in your browser too. Remove all imported games on My games deletes all of it.

If you open an imported game, it reaches us like every game page: the page's address, with the whole game and the players' names in it, goes into the web server's log for 14 days and, as a page view, into our statistics, just as for every game (see Links to games). The list on My games doesn't load any game page ahead of time, only the game you open.

Links to games

When you share a game against the computer, the whole game is in the link itself: the moves, the names you played under and the date. Games against the computer are not stored on any server, except when someone shares the game's page or reacts to it: then the link's code and the number of reactions are kept (see below). The web server's log (below) also keeps the page's address, with the link's code, for 14 days. The pages of played games don't show up in search engines.

Playing a friend online

When you play a friend online, our game server runs the game: it checks every move and keeps the clock. So it keeps what that takes, and nothing more: the moves, the names you chose and your browser's random id (so you get your seat back). It's deleted once everyone has left the table: after half an hour, or two hours if the game wasn't finished, and never later than a day. The game server doesn't store IP addresses; it uses them only briefly in memory to stop abuse. If you both choose a rated game, your player codes (as ids) are kept at the table too. There's no chat, only ready-made greetings, and every name is checked for rude words.

Class and club tournaments

The game server keeps the tournament's name, the players' names, the games and the results, and a checksum of the organizer's key (not the key itself). Players are recognized by the browser's random id (sd:online:device), not by any player code. Everything is deleted 30 days after the tournament is over, or right away if whoever organized it deletes it.

Player codes, profiles and competitions

Correspondence games, tournaments and ratings need our game server to remember you between visits. That's what the player code is for. The server keeps what that takes, and nothing more:

• Your player code: your player name and a checksum of the code (not the code itself), when it was made and last used.
• Your profile (on the player code): the portrait you drew (no photo), the motto you picked, your favorite table, the games you played (each game's code, at most 500), your progress (which opponents you have beaten or drawn with, the days with the daily puzzle, your puzzle rating with its themes, missed puzzles and highest step on the Puzzle Ladder, the lessons, the lesson tasks that come back for review, and how far you have come practicing the openings' main lines), your choices in the game's menu and your saved tables, and which profiles you have finished a game against online (as ids, at most 40, for Play again). A Play again invitation can only go to someone you have already played.
• Correspondence games: the moves, the players' names and player codes (as an id), while the game goes on and for 30 days after.
• Tournaments and cups: the arenas and cups under way, and the winners' names and scores on the results list.
• Reactions and shares: for a game that someone has reacted to or shared, the game's code is kept (what is in the link: the moves, the names you played under and the date), and how many of each reaction and share it has had, in total and this week. Who reacted or shared is not kept. A game no one has touched for 90 days is deleted. Games of the week shows only the names of our computer opponents, never the players'.
• Watching a game: nothing is kept. The players see how many are watching, but not who.
• Play now: while you wait for an opponent, your player code (as an id), your player name, the time control and your rating are in the server's memory, only for as long as you wait with the page open. Nobody else sees who is waiting, only how many. The game is then handled like an arena game: it counts toward the rating and is shown on Watch (below). After the game, the server only remembers which color you had, so you get the other one next time (until it restarts).
• Against the house players (in Play now, the arenas and the cups): for each house player you have met, how many rated games you have played against them today and the first twenty moves of your rated wins against them (the latest 30), so that the same win doesn't count twice, and the level you're at, so that the one who sits down suits you. The level is only in the server's memory and starts over when the server restarts. All of it goes when you delete your player code.
• Live games and the archive: anyone can follow the games from Play now, the arenas and the cups on Watch while they are being played: the players' names, the moves, the time control and how many are watching. When a game is over, it's kept in the archive, where anyone can see it: the names, the moves, the time control, the result, the opening and when it was played. We also keep the players' player codes (as ids, never shown), so that a new name follows and the games can be taken out, and the players' average rating rounded to the nearest hundred. The archive keeps the latest 20,000 games; the oldest make room. Games with friends, correspondence games and class and club tournaments are never shown and never kept there. If you turn off Show my games on your profile, your games are never shown, and the ones already in the archive are removed right away. A link to a game that someone has already saved still shows the game, because the whole game is in the link itself. The list and the archive aren't shown in search engines. From the archive we also make a set of data for statistics about the openings and for puzzles later on: the moves, the time control, the result, the day and the rounded rating. It has no names, no player codes, no time of day and no ids from the archive, and it isn't open to others: only we can read it.
• Logging in with your face or fingerprint (if you added it): the public half of the key, its id, a counter that shows it hasn't been copied, what kind of device it was added on (an iPhone, say) and when. Your face and your fingerprint never leave your phone or computer: they only unlock the key there.
• Device keys: a checksum for each phone or computer that logged in with a face, a fingerprint or an email link (at most 20). Log out other devices removes all but the one in your hand.
• Email as a backup (from age 13, if you added it): only a fingerprint of the address, a checksum that can't be turned back into the address. The address itself is never kept. It's used in the moment to send the email, which goes through the Postmark service (in the USA) and stays in their logs for a limited time. The links in the emails work for 30 minutes, work once, and exist only in the server's memory, never on disk.
• Notifications (if you turned them on): for each phone or computer where you turned them on (at most ten), the address your browser gives us to reach that device, and two keys that make sure only that device can read the notification. Also when you turned them on, which of the two sites you turned them on from (LaviChess or Schackdags, for the language), the device's time zone (how many minutes it is ahead of or behind UTC), which kinds of notifications you want, whether Not at night is on, and any notifications waiting for the morning. A notification travels through Google's, Apple's, Mozilla's or Microsoft's push service, depending on your browser, and says only what happened and the name of the player you're playing, never the moves or anything else about you. If you turn notifications off, or the push service tells us the address no longer works, it's deleted right away. Log out other devices turns them off on the other devices too.
• Ratings and badges (on the player code): your Live and Correspondence ratings (the number, how certain it is and how much it tends to swing), how many rated games you have played and when the latest was, your last 50 rated results (the date, your opponent's player code as an id, the result and your rating after), the moves and names of the last ten (for the links on your profile), a few counters for the badges (wins and arena games, say) and which badges you have earned and when.
• Show my profile: if you switch it on, anyone with the link can see your name, your portrait, your motto, your favorite table, your ratings and your badges, nothing else, here and on Schackdags, our Swedish sister site. It's off until you switch it on yourself, and the page isn't shown in search engines.
• What the person who runs the site sees (an admin, behind a key of their own): numbers (how many profiles, games, tournaments and reports), the reports with their game, which games are under way right now (the player names and the moves), and for each profile the player name, when it was made and last used, the number of games, rating, badges, whether it's shown, whether it's barred, whether it has an email backup (yes or no) and how many login keys it has. Never the player code, the keys or any email address. The admin can change a mean name, bar a profile from rated games or delete it, and every such step is written in a log. When someone reports cheating, an email with the player names and a link to the game goes to hello@lavichess.com.
• LaviChess Plus (if you buy it): which plan the profile has, until when it lasts and whether it renews, Stripe's ids for you as a customer and for the subscription, in a family which profiles belong to it (as ids), and the questions for the Coach (how many are left this month and how many were bought). For each purchase we keep the profile (as an id), what was bought, the amount, when, and Stripe's id for the purchase, so that a refund goes to the right place. If you withdraw from a purchase, we ask Stripe which email address the receipt went to, to check that the purchase is yours, and send the confirmation there through Postmark. The name and the address you enter then are not kept by us. A gift card is kept only as a checksum of its code, with what it is for and whether it has been redeemed. Stripe's messages to us are kept as ids for 60 days, so that nothing is counted twice, and each month totals are counted (income, refunds, cancellations, questions bought and used) without names. For each purchase, the person who runs the site gets an email with what was bought and the buyer's country as Stripe gives it; the country is not kept. The payment itself is handled by Stripe (Stripe Payments Europe, Ireland), in LaviChess's own account: the card, the email address for the receipt and the payments are with them, never with us. We send Stripe only the profile's id, never the player code or the player name. If you delete the profile, a subscription is canceled, and nothing with us points to you any more.
• Cheating reports: the game's moves and names, who reported and who was reported (player codes as ids) and when. A report stays until one of us has gone through the game; closed reports are deleted after 90 days.

When you delete your player code, everything that belongs to it goes at once: the name, the rating, the badges, the history, the keys, the notification addresses, the email fingerprint, your games in the archive and the closed reports about you. Only what belongs to others stays: your games in your opponents' history (with the name you played under), and a report about a game none of us has gone through yet. Your profile page isn't kept in the browser; it's fetched from the server every time you open it.

The web server's log

Like most web servers, ours keeps a log of every request: your IP address, the time, the address asked for (with everything after the question mark, so the game in a replay or analysis link too), your browser's name and the page you came from. We use it only to find faults and stop abuse. Only those who run the server can read it, and it is deleted after 14 days.

The Coach (Plus)

The Coach is part of Plus and answers fixed questions about your moves. When you ask, the position, what the computer found (assessments, best moves and continuations, which moves were mistakes) and the question you picked are sent to Anthropic, an American company whose AI, Claude, writes the answer. If you ask for a talk-through of a whole game, the game's moves and result are sent. Your name, your player code and anything else about you are never sent there, and there is no free text to type in.

Anthropic doesn't use what is sent this way to train its AI, and deletes it within 30 days. Only if something looks like it breaks their rules can it be kept longer, at most two years. Anthropic's own description.

On our side, how many questions you have left is kept on your player code. The answers are kept for a while in the server's memory, tied only to the position and the question, so the same question about the same position gets the same answer without costing a question. We also count how many questions are asked each month and what they cost, without knowing who asked.

What is never stored

Your email address, your face or fingerprint, your real name, your age, photos and where you live. Checking the box that you're 13 or older isn't stored either: it's only the condition for adding an email address. There is no account and no chat, and nothing to type about yourself.

Questions

Tentmaker Sweden, a sole proprietorship in Sweden, company registration number 701101-5034. Email: hello@lavichess.com.