Go rules: how to play Go, step by step

The board, the stones and the goal

Go is the simplest great game ever invented. Two players take turns placing stones on the intersections of a grid. Stones never move. The player who ends up surrounding more of the board wins. Every other rule exists to make those three sentences work.

• Board: 19×19 lines for the full game, 13×13 for a shorter one, 9×9 for learning. The nine marked points are the star points (hoshi).
• Stones: Black and White, placed on intersections, not in the squares.
• Turn order: Black plays first. White receives compensation points (komi) for going second — 7.5 on this site, which is the standard Chinese-rules figure.
• Goal: control more points at the end than your opponent.

The 9×9 board is not a toy. It teaches capture, life and death, and reading — everything except large-scale strategy — and strong players still use it to train.

Liberties: the one idea everything rests on

A stone's liberties are the empty points directly next to it — up, down, left and right; never diagonally. A stone in the middle of the board has four. On the edge it has three. In the corner, two.

A group with no liberties is captured and removed from the board. That is the entire capture rule. Stones of the same colour that touch along the lines form a single group, and a group lives or dies together: it has one shared pool of liberties.

Capturing stones and the group rule

Play a stone that removes the last liberty of an enemy group and that whole group comes off the board. A group with exactly one liberty left is in atari — one move from death — and shouting "atari" is the closest thing Go has to "check".

Suicide is illegal

You may not place a stone that would leave its own group with no liberties — unless the move captures enemy stones first, which gives it liberties. In practice this means a single empty point surrounded by enemy stones is a point you cannot play, and that is exactly what makes eyes work.

Life and death: two eyes

Because suicide is illegal, an empty point completely surrounded by one colour is a point the enemy cannot fill. That point is an eye.

A group with two separate eyes can never be captured. To capture it the opponent would have to fill both, and each fill is an illegal suicide move. A group with one eye, however large, can eventually be surrounded and killed.

"Two eyes live" is the first real skill in Go. Everything from opening choices to endgame sacrifices eventually reduces to the question: can this group make two eyes, and can that one be stopped from making them?

The ko rule

Some positions let each player capture a single stone back and forth forever. The ko rule stops that: you may not play a move that recreates a board position that has already occurred. You must play somewhere else first — a ko threat — and can only retake the ko if your opponent answers elsewhere.

Two versions exist and both are common:

• Simple ko (Japanese rules): you may not immediately recapture a single stone that was just captured.
• Positional superko (Chinese and most computer rules, including this site): no move may recreate any previous whole-board position.

Ko fights are where Go becomes a negotiation. Every threat you play elsewhere costs something, so the player with more valuable threats can win a ko they had no right to win.

Capture races, seki and false eyes

Three situations cause more arguments at club level than the rest of the rules combined.

Semeai — the capture race

When two adjacent groups are both short of liberties and neither can make two eyes, whoever fills the other's last liberty first wins. The count is not always symmetric:

• Shared liberties (points both groups touch) are filled last and count for the defender.
• The side with an eye wins a race that is otherwise level — the classic "big eye beats no eye" rule.
• The side to move effectively has one extra liberty.

Seki — mutual life

Sometimes neither side can fill without dying first. That is seki: both groups live with no eyes, and the shared points are nobody's territory.

False eyes

An eye is only real if you control the diagonal points around it. If your opponent holds enough diagonals, the surrounding stones can be captured and the "eye" fills. Many groups that look alive at first glance have two eyes of which one is false — and one real eye is not enough.

Passing, ending the game and scoring

You may pass instead of playing. Two passes in a row end the game. Then the players agree which stones are dead — stones that could not avoid capture if play continued — remove them, and count.

Area scoring (Chinese rules, used on this site)

Your score = your stones on the board + the empty points you surround. White adds the komi (7.5). The higher score wins, and the half point means there are no draws.

Territory scoring (Japanese rules)

Your score = the empty points you surround + the enemy stones you captured. The two systems almost always give the same winner, usually within a point, but they reward different endgame moves: under area scoring, filling your own territory costs nothing.

Beginners should use area scoring: you count what you can see, and you never lose a point for playing a move you were not sure about.

Handicaps, komi and fair games

Go has the best handicap system of any board game. The weaker player takes Black and places handicap stones on the star points before play begins — one stone per rank of difference — and komi is reduced to zero (or 0.5 to break ties).

A correctly handicapped game between a beginner and a professional is genuinely close. That is why Go clubs mix strengths so easily: everyone plays a real game against everyone.

Ranks

Amateur ranks run from about 30 kyu (raw beginner) up to 1 kyu, then 1 dan to 7 dan. Professional ranks run 1 dan to 9 dan on a separate scale. One rank equals roughly one handicap stone.

Notation, etiquette and common beginner errors

Reading a diagram

Columns are lettered A–T (no I), rows numbered 1–19 from the bottom. A move at the 4–4 point is called a star point; 3–4 is a komoku; 3–3 is san-san. These names are worth learning because every Go book uses them.

The five errors every beginner makes

1. Playing in the centre first. Territory costs twice as many stones in the centre as in the corner.
2. Answering every move. If a move is small, ignore it and take a big point.
3. Rescuing doomed stones. Adding stones to a dead group just donates prisoners.
4. Playing contact moves to attack. Touching a weak stone makes it stronger. Attack from a distance.
5. Filling your own eye. The quickest way to kill your own living group.

Common questions