// browser chess · wasm stockfish · daily puzzles
Playchess.Getbetteratit.
A full chess engine running inside your tab, four fresh puzzles every day, and a board that remembers every game you finish.
- Engine
- Stockfish 18 (lite)
- Puzzles
- 4 tiers, daily
- Accounts
- GitHub · Google
- Cost
- Free
// what this is
A chess site that does the work on your side of the wire.
Scacci started as a way to play a strong engine without an account, an app, or a page that spends three seconds loading advertising before it shows you a board. The engine is WebAssembly and runs locally. The puzzles come from an open database, and their solutions stay on the server, so there is nothing in the page to read ahead.
What is left on the server is the part that has to be: puzzle solutions, so they cannot be read out of the page, and your history, so it is still there tomorrow.
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The bot runs on your machine
Stockfish, compiled to WebAssembly, thinking inside your browser tab. Nothing is sent anywhere to get a move back, and the engine is only downloaded once a bot actually has to think.
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Four puzzles, every day
One each from easy, medium, hard and grandmaster, drawn from the public Lichess puzzle database. The set is the same for everyone and rolls over at midnight UTC.
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Puzzle points that add up
Every puzzle you solve is worth its tier, halved if you took a hint or played a wrong move. Finish all four in a day and your streak carries. A rating arrives with online play against other people.
// today's set
Four puzzles are waiting. All four move the streak.
Every day gets one puzzle from each tier, the same four for everyone. Solve one and you score it. Solve all four and the streak advances — which is the only thing that does.
- Easy One clean tactic
- Medium Two moves deep
- Hard A quiet move first
- Grandmaster You will want the board
// questions
Frequently asked questions
Is Scacci free?
Yes, all of it. There is no paid tier, no trial, and nothing is held back behind an account.
Where does the bot actually run?
In your browser. Scacci ships a WebAssembly build of Stockfish that runs in a Web Worker on your own machine, so moves come back without a round trip to a server. It is a 7.3 MB download and it is deliberately not fetched until you start a game against the bot — a two-player game or a puzzle never pays for it.
Do I need an account to play?
No. You can play the bot, play a friend on the same device, and solve puzzles without signing in. An account is what makes your puzzle points, your daily streak and your saved games persist across visits.
How does signing in work?
Through GitHub or Google. There is no password to choose and no verification email to wait for, because your provider has already confirmed who you are. Signing in and signing up are the same button — if you have no account yet, one is created.
Do I have a rating?
Not a moving one yet. Games against the bot and games shared on one device are unrated on purpose — neither says much about how you would do against another person. A rating arrives with online 1v1, where it will belong to your account rather than to the browser you happen to be using.
Where do the puzzles come from?
The public Lichess puzzle database, sorted into four difficulty tiers. Solutions never leave the server: the page sends the moves you play and the server judges them, so there is nothing in the browser to read ahead.
What counts for the daily streak?
All four of the day’s puzzles. Solving one, or three, does not extend it — the streak advances only when the full set is done.
Can I play someone sitting next to me?
Yes. Choose 2 Players from Play and the board takes moves from both sides on one device, with no engine involved.