Go game rules

Liberties, capture, ko. The board opens on a ko shape so you can see the rule bite.

0–00–0

Black to play — a white group has one liberty left. Take it. Take the white stone in the middle — white cannot take it straight back. That is ko.

You don’t need a booklet. Four ideas carry almost every beginner game: place on intersections, count liberties, capture when a group has none left, and respect ko so the board doesn’t flip forever. The board above opens on a ko shape so you can see the rule bite.

When to use this board

Mid-game “was that legal?” Settling an argument about ko. Quick refresh before a 9×9 blitz against the computer.

When not to

Brand-new and dizzy → how-to first. You want difficulty knobs → vs computer. Shopping for a physical board → not our store.

How

01Placement — One stone per turn on an empty intersection.
02Liberties — Empty orthogonal neighbors. Shared inside a connected group.
03Capture — Fill the last liberty of an opponent group; remove those stones.
04Ko — After a one-stone capture that recreates the prior shape, you must play elsewhere before retaking.
05Pass — When both sides pass, the game can end for counting (this board uses captures).

Gotchas

Diagonal “touching” does not connect groups and does not count as a liberty.
Suicide is usually illegal unless the play captures first — trust the engine.
Ko only blocks the immediate recapture. One move elsewhere and the point reopens.
This board scores captures, not territory. That is enough for casual 9×9.

FAQ

What happens when a stone has no liberties?: It’s captured and removed (as part of its group).
What is ko?: A short cycle rule so you can’t instantly recapture the same single-stone flip forever.
Can I pass?: Yes — two passes can end the game for scoring.
Where do I just play?: Home.