Welcome to COSUMI! On this site, you can play 5×5 to 19×19 Go(a.k.a. Igo, Baduk, and Weiqi), which is a well-known ancient board game. If you do not know how to play Go, please look at Wikipedia(Rules of go) first, and then try a 5×5 game that is just right for a beginner like you. Enjoy!

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Japanese Rules(Territory scoring)
5×5 to 9×9(Level 0)No komi, and your color is always black
9×9(Level 1) to 13×13,
15×15 to 19×19 Even Game
Komi is 6.5, and your color will be decided at random
15×15 to 19×19 Handicap GameNo komi
HTML5 Version for Mobile
Yeah... COSUMI has lost 33,690,177 games already...