Why did I lose by 0.5 points

It seems like i’ve won but the game says i lost by 0.5 points. Does anyone know why? Im black in this game and should have more territory than the opponent


Hi Lucas, welcome to OGS.
Is there perhaps komi?


I’m not sure about the details for this app, but typically White gets a certain number of komi (compensation points) for playing second.

White has 11 points if territory and black has 16. I don’t know how many captures there have been, but White might still have the edge due to komi.

Does that app provide some break down of the scoring?

There is komi of 6.5 points and korean/japanese rules, but ive heard that chinese or japanese doesnt really make a difference in score most of the time. Thank you for the quick responses.

Well, white has 11 points plus komi of 6,5 so that is a total of 17,5 points.
Black has 16 points so white wins by 1,5 point (maybe we forgot a prisoner).
I think that B: - 0,5 means that Black has 0,5 points less than White.
So I think you win by 0,5 points. :grin:

About difference / similarities of rules sets: I am not good at this, so I am not going to try to answer that one.

I love that app but there isn’t score breakdown

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In Chinese scoring ( count stones+free intersections)
White: 38+komi
Black: 43

Prisoner doesn’t matter.

So white wins if komi 5.5 or more.

For Japanese scoring I wonder about prisoners. Cpu (1) means maybe cpu has 1 prisoner?

For equivalence of rules, white should give a prisoner to black if he’s not the last one to play (so there will be the same quantity of white and black stones on the board).
I am a bit lazy to check who finished the game here.

I think the usual komi on OGS is 5.5 on 9x9 besides this, but it doesn’t matter here as white wins already by 0.5 with 5.5 komi (and by 1.5 with 6.5 komi)

I guess he’s black and CPU is white, so he lost.

Yes black has -0.5 it in other words white has +0.5 and wins. I have this app but can’t work out what Komi is exactly. But the answer to the original question is “because of Komi”.


That is the strength of the AI.
You can choose many levels. 1 is the lowest and is compared to 18k

Komi in that app is 6.5 under Japanese rules and 7.5 under Chinese.


@lucas.grossmann, I took the liberty of moving the text from your titles to the body of the message, and instead make a summary of the message to be the title, as is customary on forums.