How to play
Two players, Black and White, take turns placing one stone on an empty point where the lines cross. Black goes first. Stones never move once placed.
The empty points next to a stone (up, down, left, right) are its liberties. Stones of one colour that touch share their liberties as a group. When you take a group’s last liberty, it’s captured and comes off the board.
You can’t play a stone that would have no liberties, unless it captures something. And you can’t take back a single stone straight away if that would repeat the board (this is called ko): play somewhere else first.
Instead of playing you can pass. When both players pass in a row, the game ends.
Scoring
Your score is your stones on the board plus the empty points that only your stones surround. White gets 7.5 extra points (komi) for moving second, so there are no ties. The page shows a running count under the board.
This page counts every stone left on the board as alive, so before you pass, capture any of your rival’s stones that are trapped inside your area. It costs you nothing: playing inside your own area doesn’t lower your score here.
Tips
Start near the corners, then the sides, then the middle: corners need the fewest stones to fence in. A group with two separate empty points inside it (two eyes) can never be captured. Try 9 × 9 first; 13 × 13 games are longer and leave more room for big plans.