Go is a territory game. Black and White take turns placing one stone at a time on the 9×9 board. Whoever controls the most points at the end wins.
Liberties
A stone’s liberties are the empty points directly next to it (up, down, left, right — not diagonal). Stones that touch each other share liberties as a single group.
Capture
When you fill the last liberty of an opponent group, that group is removed from the board.
Suicide
You cannot play a move that would leave your own group with zero liberties — unless that same move captures opponent stones first, freeing up a liberty.
Ko
You cannot immediately recapture a single stone that just captured one of yours — you must play somewhere else first. This prevents an endless back-and-forth.
Pass & ending the game
You may pass on any turn. When both players pass in a row, the game ends and we count the score.
Scoring — two systems
Pick a rule before the game starts (it locks once you place a stone).
- Chinese (area): your stones on the board + empty points fully surrounded by your color. Captures don’t score directly — they shape territory.
- Japanese (territory): empty points fully surrounded by your color + prisoners you took. Stones on the board don’t score on their own.
Same game usually picks the same winner under either rule; only the absolute scores differ.
Komi
White gets bonus points to compensate for moving second. Standard komi is 7.5 Chinese / 6.5 Japanese; the half-point guarantees a winner — no draws.
Handicap
Black can start with 2–9 stones already placed on the star points to balance a game between players of different strength. With handicap, White plays first.
Dead stones
Once both players pass, the game enters a marking phase. Click any stone to toggle its entire group as dead. Dead stones count as captures, and their points become the surrounding color’s territory. Click Done to accept, or Resume to keep playing.