Play Computer-Go Online at

I just added a new feature at the capability of playing computer-go online, against the GnuGo engine. You can try it out here and please let me know what you think. If 361points doesn’t work well (it happens when many people try to play at the same time), one can also play computer-go on the original page. I am using the wonderful, recently released open-source library EidoGo for the user interface. I coded the server side myself – while EidoGo does come with integrated PHP scripts for GnuGo interaction, my website is based on Django, which is a Python web development framework, so I had to write the equivalent functionality in Python. Also, the first 9×9 game I tried on the EidoGo website, I realized that after both players pass there is no ending of the game: I found that frustrating so I added an “Estimation” button which makes a special call to GnuGo to retrieve a score estimation. That is pretty accurate in the end of the game, provided GnuGo can understand the status of all stones on the board. I also added the possibility to select the color one wants to play with, and the GnuGo level. I know GnuGo has interfaces in most of the popular SGF viewers – but being able to play against it online makes it so convenient. Myself I haven’t tried playing computer-go in a couple of years I think – and now that I’ve played several games against it while testing my website I was surprised of how well it does in many close fights. I got captured a couple of times very unexpectedly so be warned to count your liberties twice :-) .

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42 Responses to “Play Computer-Go Online at”

  1. goulo says:

    Quite nice, although it’s odd/annoying that one must click “Estimate” to see the score at the end.

  2. Chris says:

    It’s a great initiative. As we can see, gnugo and the like appear to be frustratingly a little bit short of a being a complete tool. Ideally, we need gnugo to report which territory belongs to which player (coordinates that belong to each colour) and eidogo needs to be able to support querying this information (and displaying it). I dare say there may already be protocols to cover this information? Also, a double pass should trigger a game-end process.

  3. Sorin says:

    Goulo and Chris – thanks a lot for trying it out and providing feedback!

    As far as I know, GnuGo doesn’t show territory when scoring; it does have the option of finishing the game (it gives a sequence of moves) besides providing the actual estimate.
    I’ll get in touch with the developers to clarify this.
    If not available, I’ll have to look for another way to achieve this.

    Also, I find it strange that, when playing white, if the first black move is a hoshi it plays in contact with it; when I tried GnuGo outside of my website settings I’ve seen it play more varied openings, I wonder if I’m doing something wrong…

  4. Tommie says:

    quite impressed.
    Program is sometimes very strong, punished me,
    then made incredible errors,
    collapsed also technically in the end

  5. Tommie says:

    I made a screenshot shortly after I gained the upper hand due to the fighting errors and shortly before it ‘bugged’, i.e. didn’t move anymore, as I could move several times in a row (then stppoed).

  6. Sorin says:

    I had the same experience: got captured several times in close fights, when not paying enough attention.

    About the program not being responsive: I have to figure out how to use EidoGo better in that respect. I added a “retry” feature in case the request to GnuGo on the server side fails, but occasionally it will give up anyway.
    In those cases it switches to a usual SGF editor, when one can make moves for both sides. Is that what happened to you as well, or were you making several moves in a row for just your color?

    I’d like to see the screenshot – is it easy to add it to the godiscussions thread I started, in case they allow image uploads? Or you can just email it to me: soring at gmail dot com

  7. Martin says:

    Great work! It’s been a while since I tried gnugo and it really improved over the years. Maybe you can add mogo as an engine later on.
    You might encounter quite some traffic after a while when we start pointing our friends to your gnugo-Interface :) . Great!
    Best regards, Martin

  8. Sorin says:

    Glad you liked it! I will see if adding Mogo can be done – that’s a great suggestion, thanks a lot!

    > You might encounter quite some traffic after a while when we start pointing our friends to your gnugo-Interface :) .

    Bring it on :-)

  9. Francis says:

    Very nice!
    Easy to use and v. convenient. Many thanks.
    As other shave mentioned, the prog makes a few odd calculations, but then I never played a Go prog that didn’t.
    The only prob with the thing, really, is that every game I have played has been interrupted by the message, “server error, please restart in a few minutes” which kills the game. Is there any way to make this less likely to happen?

  10. Sorin says:

    Hi Francis,
    Thanks for trying it!
    I both increased the number of retries (in case there is a failure communicating with the game server) and changed the way gnugo interaction goes. I hope this will decrease the type of failures you described.

    Please let me know whether it works better for you.

  11. Rich Osborn says:

    I have tried playing your program four times, and every time, the games get no further than about 30-35 moves before the program freezes up. I don’t THINK this is because it is completely dazzled by my moves, but I suppose it could be….

  12. Sorin says:

    Rich: sorry about the bad experience… If you tried 4 consecutive times, it may have been because of a particularly high server load at that time of the day, but this is definitely not supposed to happen, and it shouldn’t be induced by your moves either :-)

  13. Akihito says:

    Make it stronger

  14. Akihito says:

    make it 1 dan level

  15. Sorin says:

    Akihito: I am only using the GnuGo engine for now, I haven’t contributed to its strength.
    Making a Go program 1-dan level on 19×19 is really hard – and every Go programmer’s dream. Won’t happen for the next 10 years, that’s my bet.
    As for 9×9 boards, the 1-dan threshold was reached (and exceeded) by Mogo already:

  16. Tommie361 says:

    Hello Sorin,

    only read now your entry from December.
    I cannot find the screenshot at this computer right now,
    I will try to find it.

    Ha, won today on 9×9 by W+37.5 (where the computer should have won).

  17. Lizzie says:

    HAH! This thing has really evolved since I last played a couple of days ago. The game’s faster, moves more complex and I’m having so much more trouble too (well, I *am* a beginner, so I’d have trouble either way). Just now, it threw a first hand tengen at me. Now I’m expecting it to start the next game at 5, 5. I know what I’ll be playing if it does that, too… :P

    Only problem is that it keeps showing this ‘can’t retrieve game data’ thing all the time, so I never managed to finish a game :(

  18. Aki says:

    Hello there, this is a really nice program you have here. i cant get this version of gnugo to work on my goban so i play this quite often. however some times the “There was a problem retrieving the game data” error happens in like 4 or 5 consecutive games and it is a bit disappointing :( any possibility of improving the program stability? also a possibility to save the game record as a sgf file would be a nice addition as i like to go through my games later on even if it’s against a program. anyway thanks for the great and useful application ;) (good looking one too)

  19. Gregory Wonderwheel says:

    I haven’t played in many many yers so it was a great way to start to get back into the Go frame of thinking…… but the data retrieval error kept showing up and crashing the games so it was very disappointing.

  20. Filip Lindberg says:

    I thought that the game itself was great, though the hardest level was a little bit too easy! It bothers me that you are able to commit suicide, maybe there could be an option button to turn that off? :) ( It’s illegal in most Go gamestyles) and if you change color from black to white then the scorekeeper says that you are the machine (Really annoying.) If you could change the name from Gnu..Something to White it whould really clarefy things!:) (Im from sweden so please, be gracefull on my spelling.)

    Other then that! Great work! :D

  21. yinyango says:

    [abia am reusit sa-l bat (cu 3 pietre handicap) pe 19x19 la nivelul 10.]

    soo, great work you’ve done here. this online Go game helped me find your site, which made me love Go even more. thanks!

    (anyway… i wonder – can’t you do anything about that “error retrieving data”? that’s the only minus i could see so far.)

  22. Heiko says:

    Hi there, just wanted to say “thanks” for the great site. I really got into Go over the last weeks although its buggin me that im losing such often against the computer. So as I said: thanks alot! :)

  23. Tim says:

    I the middle of my games it keep saying There was a problem retrieving the game data. That was very annoying. But this is the best Computer GO on the net. Make so updates to make the program rum smoother and it will be even more amazing.

  24. Rich says:

    The program keeps having a problem retrieving the game state. It even did this when I refreshed the page, before a game even started, and after my first move. Isn’t the latest official release of GnuGo 3.6? Maybe that one would be more stable. This has been getting worse for me over the last couple weeks. Lately it’s completely unplayable, because of that error. I usually play about 11 pm Pacific time. Don’t know if that might be part of the problem.

    On the plus side, the GUI is nice. I will check back occasionally.

  25. Michael says:

    I’m getting the same error as the above people. I try a few times a day and have tried with both a Mac and PC. Hope it comes back up because it really helps me get through work :P

  26. Sorin says:

    Increased the server resources – hope it’s going to behave better and see less problems…
    Unfortunately this is not a perfect solution: as long as that page becomes more popular, it’ll crash again at some point.
    I’ll have to think of a long-term fix for it.

  27. yeye says:

    Hey, nice website to play go online against gnugo.
    Congrats for this.
    But, unfortunately, it doesn’t work anymore since a few days : the java applet doesn’t appear at all :(


  28. Sorin says:

    Hi Yéyé – fixed now…

    Thanks a lot for letting me know!

  29. HI says:

    Good job. I have been plan to do such a website too, since I am very interesting in playing go game recently.. But I found it involved a lot of job, and might be time consuming…. so I am kind of giving up now… It’s good to see someone has already fulfilled my dream~~~

  30. michael egan says:

    I love it,BUt, sometimes I think it cheats on me, taking my turn if linger too long! Also on the very few occasions I am getting a lead, it packs up on me. it`s brilliant.

  31. Sorin says:

    I don’t think it takes the opponent’s turn :-)
    But indeed, it’s quite sharp in local fights, so it can turn a game around quickly if the opponent make some tactical mistake.

  32. Abe says:

    Great application!

    Is there any chance you’ll add an “undo” feature for mis-clicks, bad moves, or variations? Right now it seems that when I click the “back one move” button, the engine turns off and the applet becomes just an editor. It would be very interesting to be able to play out different variations from a given position.

  33. Sorin says:

    Hi Abe,

    Great suggestions, thanks!!
    Also, being able to save and continue the game later would be nice too…

    Not sure when I’ll have time for these, though – hopefully “soon”.

  34. Taki-chan says:

    I liked it. I just learned how to play go literally 2 minutes ago.

  35. Sorin says:

    Taki-chan: glad you liked it, and welcome to the wonderful world of Go!

    You may find the “First steps” page useful:

  36. Paul says:

    Great implementation. Its always hard to find an opponent, so its nice to have a computer to challenge my game. I have got to learn to protect my groups better!


  37. ron shafer says:

    Many thanks. Very excited to find this.

  38. joe says:

    its good but it has a few problems. first if i accidentally play an illegal move, instead of placing my stone somewhere else it takes it as a turn and goes ahead with 2 straight moves! another problem, though im not quite sure on the rules is double ko. i have twice now been in game that halted because the computer and i would be stuck in 2 ko positions on the board.

  39. Shawn says:

    great tool to keep me sharp, but it doesn’t recognize seki. i would have surely won a game if it had not counted the seki as the opponent’s points

  40. Micro102 says:

    This is awsome and has improved my game immensly, however the inability to backtrack because of a mistake is VERY annoying…Probably turns a lot of people off using this. The difficulty adjuster doesn’t seem to do much either.

    It also seems to try and merge all rules together.

  41. Eric says:

    This is great, thanks.

    I don’t really understand its scoring estimate though. It seems to give the computer way more points early game for no reason.

  42. Stu says:

    Very Nice!
    Great Effort, but when I give it 2 stones on a 9X9 board, it seems I often stump it. That is to say, it sometimes “thinks” for over 10 minutes before I give up on it.