Five in a row. Infinite strategy.
Gomoku (also known as Five in a Row or Gobang) is a classic two-player strategy board game played on a 15x15 grid. Players take turns placing black and white stones on the intersections. The first player to get exactly five stones in an unbroken row — horizontally, vertically, or diagonally — wins. This free online version lets you play against AI at three difficulty levels, from casual to genuinely challenging.
You play as Black and move first. Click or tap any empty intersection on the board to place your stone. The objective is simple: get exactly five of your stones in a continuous line in any direction. The AI responds with white stones, trying to build its own lines while blocking yours. Build threats in multiple directions simultaneously to overwhelm your opponent. The game ends immediately when either player completes a line of five.
Gomoku is about getting 5 stones in a row, while Go is about surrounding territory. Gomoku is much simpler to learn but still strategically deep. Both games use the same type of board and stones, but the objectives and strategy are completely different. A game of Gomoku typically lasts 20-50 moves, while Go can last over 200.
Yes, on a 15x15 board with standard rules, the first player (Black) can always force a win with perfect play. This was proven computationally. Because of this inherent advantage, tournament rules often restrict Black's opening moves to keep the game fair and competitive.
Starting in the center gives the most flexibility, as it maximizes the number of possible lines you can build through that point. From there, build threats in multiple directions simultaneously to overwhelm your opponent. Creating "forks" — simultaneous threats that the opponent cannot all block — is the key to winning.
If you enjoyed Gomoku, try these: Connect Four · Othello · Checkers
Last updated: April 2026 · whatifs.fun — Free interactive games, experiments & simulations