Play Gomoku Online
Five in a row on the Go board — simple rules, deep strategy.
How to Play Gomoku
Modes: vs AI · 2 Players
Gomoku is played on a Go board. Black moves first and the players take turns placing one stone on any empty intersection.
The goal is to be the first to place five of your stones in an unbroken line — horizontally, vertically or diagonally.
In vs AI mode you play Black and the computer answers each of your moves. Pick Easy, Medium or Hard to set the AI strength.
In 2 Players mode two people share the screen and take turns on the same device.
Rules
Players alternate placing one stone per turn on an empty cell.
Five or more of your stones in a row — in any direction — wins the game.
There are no forced moves or handicaps; Black starts with a small first-move advantage.
If the board fills completely with no winner, the game is a draw.
Scoring
| Win | place five in a row first |
| Time | fastest win wins |
History & Origins of Gomoku
Gomoku is one of the oldest games played on a go board. Known in China as wuziqi, the five-in-a-row game has been recorded there for centuries, and it travelled to Japan, where the name gomoku narabe — meaning five stones — and the shortened form gomoku took hold.
Japan later developed renju, a formal tournament version that adds opening restrictions for the first player, while the simpler freestyle five-in-a-row spread across the West as a quick board and pencil-and-paper pastime. Gomoku owes its reach to a rule anyone can grasp: make a line of five.
ThinkyPlay renders gomoku with pure CSS stones and grid lines, clean and crisp on any screen, and offers two board sizes: a brisk 9×9 grid or the standard 15×15. Challenge a threat-scoring AI that sharpens across Easy, Medium and Hard, or let two players share one keyboard and settle it face to face.
Common Mistakes to Avoid
- Opening far from the centre on Medium or Hard — both levels favour central lines, so a corner start lets the AI build the best threats first.
- Attacking without ever blocking: an opponent’s open three becomes an unstoppable open four if you spend your turn chasing your own line.
- Underestimating the difficulty switch — Easy forgets subtle setups, but Hard reacts to any open three and answers an open four almost immediately.
- Building threes along the edge, where one end of the line is already closed and easy to cap.
- Never checking for the AI’s open four: a four with both ends free is a forced win, so count the opponent’s stones before starting your own push.
Tips & Strategy
Control the center early — it opens the most lines in every direction.
Never ignore an opponent’s open three: block one end before it becomes a four.
A four with both ends open is a guaranteed win; build it and your opponent can only delay.
Look two moves ahead: setting up two open threes at once is almost impossible to stop.
Use the Hint button to see where the AI thinks you should play.
Frequently Asked Questions
- Is Gomoku free to play?
- Yes — Gomoku on ThinkyPlay is completely free, with no download and no sign-up.
- What is the difference between Gomoku and Go?
- Go is a capturing game played to surround territory. Gomoku is simpler: the first player to line up five stones wins.
- Can I play Gomoku on my phone?
- Yes — tap any intersection to place a stone. It works on desktop, tablet and mobile.
- How strong is the Hard AI?
- Hard looks several moves ahead and blocks open threes while building its own threats. Most casual players find it a real challenge.
- Can two players share one device?
- Yes — switch the mode tab to 2 Players and take turns tapping the board on the same screen. You only need one device, no accounts and no extra pieces.