Why sometimes 7.5 komi, sometimes only 0.5 komi?

I played a rated game earlier, white (me) had only 0.5 komi. i was 8k, opponent was 9k. can someone explain it?

8 kyu is one stone stronger than 9 kyu. The handicap for that difference is the komi. So the stronger player doesn’t get komi in handicap games. 0.5 is just there to prevent tied games.

1 Like

thanks Pempu.
but i just saw 11k vs 10k with 6.5 komi, ranked game as well.

The creator of the challenge can decice the settings. It is up to the other player to accept the settings. If they agreed on even game with 6.5 komi then so be it. It just doesn’t make much sense for the stronger player as he/she has more to lose than to gain. The ranking system works so that one stone difference in rank equals to one handicap stone.

EDIT: Other “solution” could be that one of the player were different rank when the game started. I’m not quite sure how OGS displays historical rankings in the game window or in the game list.

Thing is, if I wanted the game to be ranked, I was not allowed to set komi as I wish (custom). So I do not understand why others’ games can be so differently in komi while they all show “ranked”.

I understand the common sense about komi. In China, back to the time I learned play going, I only knew komi was 5.5, and the difference between ranks was taken care by handicap (that is to say, if I were 1k, play with someone 3k, handicap would be 2 stones, but komi still stay as 5.5).

Thanks pempu for explaining.

Playing without komi (the half point is just a tie breaker) is known as a one stone handicap game. So if the ranking difference is only one no extra stones are placed on the board.


can someone explain to me that why the games i challenged always 7.5 komi (i.e, the game i just finished, 9k vs. 7k), but the games i observed with same rank difference were mostly 6.5 komi? and they all are ranked games so i suppose they all were set as “auto”?

Most people use Japanese rules when creating challenges (it’s the default on OGS). In Japanese rules, the komi is 6.5 points. You probably use Chinses rules in your own challenges. Chinese rules use a 7.5 points komi, due to differences in scoring method vs Japanese rules (area scoring vs territory scoring). Both rulesets are equivalent.

See http://online-go.com/docs/go-rules-comparison-matrix, http://senseis.xmp.net/?Komi, http://senseis.xmp.net/?TerritoryScoring, http://senseis.xmp.net/?AreaScoring for more information.


thanks VincentCB! That explains!

I’m having the same problem. I accepted a challenge from someone with a higher rank and they had the komi set to +5.5 for them. It was a 9X9 grid so I had no chance of winning from the beginning. I accepted another game on a 13X13. I am a 19K, the challenger was a 17K. He had a +5.5 komi. I tried to create my own game so I could have a +5 komi but it won’t let me change the settings.


I think you mistook your problem for another issue. It is NORMAL for white to have 5,5 points komi (https://senseis.xmp.net/?Komi) on 9x9. It is a compensation for black having the first move which is an advantage.
In ranked games this rule is enforced, as it is the tradational and widely accepted way to play. To play a ranked game without this compensation would basically be cheating, hence it is not allowed :slight_smile:

If you want to be the one with the “bonus” points pick your color as white. But that does not mean you are better off. (although there is of course a discussion whether komi for 9x9 should be more or less 5,5 points is nowadays standart)

alternatively you can enable handicap, which will give white less komi - or even bonus stones to black, should white be much stronger.

I don’t think I’ve ever won a 9X9 game by more than 3 points. Guess I will have to stay away from those

Just today you have won by resignation! Being at least 20 points in the lead

Do not stay away. 9x9 is fun. I know you feel like 5 points is a lot - it is common for new players to feel that way - but having the first move is also a lot.
You will just have to trust the judgment of skilled professional players who made up that rule. And as you play longer, you will see how having the first move, gives you a lot on such a small board. Not having the compensation black would be very OP.

It is very interesting to try both sides. While white has to try and carefully keep his lead, black needs to be active and pressure the oponent, not letting his first move advantage go away.


According to nice book “81 little lions” by Francisa, on 9x9 “komi is a bitch”! :wink: