Many players meet the same unpleasant surprise in their first online games. The game is clearly over, they are clearly ahead, both players pass, and the final count says they lost, or won by much less than expected. The reason is almost always the same: dead stones were left on the board.
This article explains why that happens on this site, how to recognise dead stones, and how to remove them without giving away points.
How the count works here
This site uses area scoring with komi 7.5. When both players pass in a row, the game ends and the board is counted exactly as it stands: each player's stones plus the empty points reachable only from that player's stones.
The count does not ask which stones are "really" dead. It cannot read your intentions. A stone on the board is a stone on the board. This is a strict and fair rule, and it removes the arguments that can happen in face-to-face games about whether a group is alive. But it means the players must finish the job themselves.
What goes wrong with dead stones
Imagine your opponent has two stones inside your large territory. They have no chance of living: you surround them completely, they have no eyes, and any fight is hopeless for them. In a face-to-face game under traditional rules, both players would agree these stones are dead and remove them at the end.
Under the strict count used here, if you pass without capturing them:
- The two stones count as points for your opponent.
- The empty points around them can be reached from both colours, so they count for nobody.
A small group of dead stones can easily swing the result by ten points or more.
How to recognise dead stones
A group is dead if it cannot make two eyes and cannot connect to a living group, no matter how the owner plays. Signs include:
- It is completely surrounded by your stones with no escape route.
- The space inside is too small for two eyes.
- It has one eye at most, and the rest of its space can be filled.
If you are unsure whether a group is dead, it is not safe to leave it. Either read it out fully or keep playing until the situation is clear.
How to capture them without losing points
Here is the good news: under area scoring, playing inside your own territory costs nothing. Each stone you place counts as a point, exactly like the empty point it covered. So you can take the time to capture dead stones calmly, one liberty at a time.
A safe procedure:
- Close all borders first, so your opponent cannot gain points elsewhere while you capture.
- Start filling the liberties of the dead group from the outside, keeping your own stones connected.
- Make sure none of your filling moves leaves your own stones in atari.
- When the dead group has no liberties left, it is removed from the board.
- Check again for any other dead stones.
If your opponent plays inside your area to delay the capture, you answer and keep going. Each exchange is score-neutral under area scoring.
What if my opponent refuses to pass?
Sometimes your opponent keeps adding stones inside your territory, hoping to confuse you. Stay calm. Under area scoring each of their stones must eventually be captured, and each capture returns the points to you. Answer each move carefully, capture what needs capturing, and pass only when your area is clean.
What if my stones are the dead ones?
If you realise that one of your groups inside your opponent's area is dead, you do not need to do anything special. Your opponent should capture it. If they pass without capturing it, the count will treat it as alive, which helps you. It is not bad manners to pass in that situation; the rules of this site put the responsibility on the player whose territory contains the dead stones.
Seki is not dead
A group in seki shares liberties with an opposing group, and neither side can capture the other. Seki groups are alive, and you should not try to capture them; attempting it usually puts your own stones in atari. See seki and scoring.
A quick end-of-game checklist
Before passing on this site:
- All borders closed.
- All dead stones in your area captured.
- All neutral points filled, checking for shortage of liberties.
- No group of yours left with a hidden weakness.
This checklist takes only a few seconds, and it prevents almost every surprise at the end of a game.
Why the site uses this rule
Counting the board as it stands is sometimes called a Tromp-Taylor style of scoring, after the concise rule set that popularised it. It has clear advantages for online play: no arguments about life and death, no need for both players to agree on which stones are removed, and a result that the computer can compute instantly. The price is the small amount of extra work at the end, which area scoring makes free.
Practice
Play 9×9 games against the computer on the home page and make the checklist part of every ending. At the lower levels, the computer sometimes leaves stones inside your area; that is perfect practice for capturing them calmly. Against people on the online page, the habit protects you in every close game.
If you sign in on the account page, your games are saved. When a final count surprises you, replay the last moves and look for stones that should have been captured. For more on the final count, read area scoring explained.
A story many players recognise
A player finishes a 9×9 game feeling confident. Their territory in the lower right is large and safe, and three white stones sit inside it with no chance of living. Both players pass. The count appears, and White wins by a few points. The player is puzzled until they replay the game and see the three white stones still on the board, counting for White and turning a dozen points of territory into neutral space.
Once this has happened to you, you never forget it. The purpose of this article is to let you learn the lesson without losing the game first. Treat capturing dead stones as part of the game, not as a formality after it.
Frequently asked questions
Why did my score change after we both passed?
Probably because dead stones were still on the board. The site counts stones as they stand after two passes.
Does capturing dead stones in my territory cost points?
No. Under area scoring, your stones count as points, so filling your own area is score-neutral.
Should I capture my opponent's dead stones even if they obviously cannot live?
Yes. On this site, a stone left on the board counts as alive, however hopeless it is.
What if I am not sure a group is dead?
Then do not treat it as dead. Read it out, or keep playing until it is clear.
Should I try to capture a group in seki?
No. Groups in seki are alive; trying to capture them usually puts your own stones in danger.
