Play Chess Against the Computer — Free

Easy looks one move ahead and answers in under half a second — the right opponent for someone learning, because it lets mistakes through. Medium looks two moves ahead, Hard three and Master four, thinking up to four seconds before replying.

The engine never plays at random. It searches by negamax with alpha-beta pruning and extends the search through captures until the position is quiet, which is what prevents the absurd move in the middle of a trade. Its evaluation adds up material, the quality of the square each piece stands on, the bishop pair, and in the endgame the king that has to walk forward.

At lower strengths it is not blundering on purpose — it simply sees less far. You beat Medium with a two-move trap and Master only with a long-term plan.

The search happens inside the browser, on a thread separate from the one drawing the board. That is why the game never freezes while the computer thinks — the board stays responsive, the 3D scene included, and you can orbit the camera while you wait.

Because nothing travels to a server there is no queue, no latency, and the game behaves the same on a bad connection. There is no signup either: the page opens ready to play.

Play White, Black, or leave it random. Playing Black against the computer is the closest exercise to a tournament game, because it forces you to answer an opening you did not choose.

The clock is optional. Untimed, to study a position without hurry; 3 minutes with a 2-second increment, 5 minutes or 10 minutes when the point is training fast decisions.

The game is saved in this browser and resumes where you left it, even if you wander off to the shop or the leaderboard and come back later.