Play Atari Go Online
One captured stone is enough to win the Atari Go board game. Atari Go makes this small rule easy to explore: inspect connected groups, count their distinct liberties and preview a placement before committing it. Play a full 9×9 game against the computer or another person on the same device, or work through twenty original small-board capture studies.
How to play Atari Go online
- Choose Study challenges, Full CPU match or Two players.
- Inspect a stone to see its connected group and its distinct liberties.
- Select an empty intersection and read the placement preview.
- Press Place stone. Capture any enemy group first to win.
Controls
Select an intersection to inspect or preview it, then press Place stone to commit. Arrow keys move focus, Enter inspects, Space places, H hints, P plays a hint and U or Ctrl+Z undoes. Help and Board & rules open separate panels.
A tip before you start
Before filling an opponent's last liberty, check whether your stone actually captures. A surrounded placement can be legal when removing the enemy group creates room to breathe; without that capture, the same placement may be suicide.
A capture race, not territory scoring
Black starts on an empty board in full games. The players alternate placing one stone on an empty intersection. Stones never slide or jump. When a connected enemy group loses its last liberty, it is removed and the player making that first capture wins immediately. There is no territory count, komi or endgame scoring. This edition has no passing; if no legal placement remains, its explicit digital convention is a draw.
Count empty points, not connecting edges
A group connects through horizontal and vertical neighbors. Diagonal stones are separate. Each empty neighboring intersection is one liberty even when two stones in the group touch it. For example, black stones at A1, B1 and A2 on a 3×3 board have three distinct liberties: C1, B2 and A3. B2 touches two black stones but counts once.
Capture is checked before suicide
Imagine a 3×3 board with black stones in all four corners and white stones at B1, A2, C2 and B3. The center B2 is empty. Black may place at B2: all four white groups lose their last liberty and are captured, giving the new black stone liberties. This wins immediately. Filling a point that leaves your group without a liberty and captures nothing is illegal.
Inspect before you commit
Select an occupied intersection to inspect its whole connected group. With the Liberty lens on, green rings show the group and green dots show its distinct liberties. Select an empty point to preview the resulting liberties or capture. The board changes only when you press Place stone, which also gives small-screen players a chance to correct a selection. Turn the lens off when you want to count independently.
Twenty original capture studies
Studies use compact 3×3, 4×4 and 5×5 boards reached by legal, capture-free opening moves. You must force the first capture within a stated budget against exact computer replies. The shortest guaranteed plans grow from one to five of your turns. Later positions include more consequential choices and larger continuation trees; the board size does not increase at every level. These are teaching exercises, not a Go rank or a promise about full-game difficulty.
A full game alone or with a friend
Full games start from an empty 9×9 board. The computer uses bounded search and can make mistakes. Other side starts a new CPU game with your color switched after confirmation. Two players take turns on one device; there are no online rooms. Undo restores your placement and the computer reply in CPU play, or one placement in local two-player play.
Hints, saves and another attempt
A study allows two hints, and Undo does not refund them. A hint preserves a shortest forced capture when that still fits the turn budget; otherwise it suggests undoing. Full-game hints are computer suggestions, not winning guarantees. Unlocked studies, best scores, sound settings and full-game action histories save locally when storage is available. A reloaded study starts again. Play free online with no ads, download, account or timer.
Frequently asked questions
Is Atari Go the same as ordinary Go?
It uses Go-style connected groups, liberties and captures, but the first capture ends the game. Atari Go does not score territory or use komi.
Do diagonal stones share liberties?
Diagonal stones do not form a connected group. Count each group's horizontal and vertical empty neighbors, counting a shared empty point only once.
Why can I sometimes play into a surrounded point?
Captures are removed before checking your own liberties. A placement that captures and creates a liberty is legal. A placement with no liberty and no capture is suicide and is rejected.
Can I play with another person?
Yes. Select Two players for a 9×9 game on the same device. This game does not provide online rooms or remote matchmaking.
Are the computer and hints perfect?
Study replies and study hints use exact results for those small positions. Full-game CPU play and hints use bounded search and are not perfect.
Can I pass or continue after a capture?
No passing is used in this edition. The first capture ends the game immediately, so ko recaptures and territory scoring never arise. No legal placement is treated as a draw under the stated digital convention.
Will my progress survive a reload?
Unlocked studies, best scores and sound settings save on this device when browser storage works. Full games resume from their validated move histories; studies restart from their original positions.
About Atari Go
One captured stone is enough to win the Atari Go board game. Atari Go makes this small rule easy to explore: inspect connected groups, count their distinct liberties and preview a placement before committing it. Play a full 9×9 game against the computer or another person on the same device, or work through twenty original small-board capture studies.
Play this puzzle / casual game in the embedded browser player. No app installation or MangoFun account is required. Follow the instructions shown inside the game; controls and device support depend on the title.
