Home » Play Games » Gomoku

In this guide

• How to play Gomoku
• The rules, line by line
• The three AI levels
• Gomoku or Connect Four?
• Strategy tips that win games
• Questions and answers

How to play Gomoku

Press Play and the board is live. You are black, and black always moves first in Gomoku. That first move matters, so the centre of the board is the classic opening. The centre crossing is marked H8 in the move list, and it is a strong home for your first stone because lines can grow from it in every direction.

Tap or click any crossing of the grid lines to place a stone. One tap is all it takes. There is no confirm step and no drag. On a computer you can hover first and a faint ghost stone shows exactly where your stone will land. The AI answers at once, and the gold dot marks the newest stone so you never lose track of the game. The full move list sits under the board in board notation, so you can replay the story of the game at a glance.

Your one job is simple to say and hard to do. Build a line of five of your stones, across, down or on a diagonal, before the AI builds one of its own. Every stone you place should either grow your own lines or slow the AI down. When a game ends, the winning line lights up in gold and the match score updates. The score runs across games, so a quick rematch is always one tap away with the Play again button.

Mistapped? On the Casual and Skilled levels the Undo button takes back a full round, your last stone and the AI reply together. On Master there is no Undo, because every move there is final. The New game button starts a fresh board at the same level without recording the game you left, and Resign hands the current game to the AI when a position is truly lost.

The rules, line by line

Gomoku has very few rules, and that is its charm. The board has 15 lines each way, which gives 225 crossings where stones can sit. Players take turns placing one stone of their colour on any empty crossing. Stones never move and are never captured. The first player to make an unbroken line of five stones wins at once. The line can run across a row, down a column or along either diagonal.

One rule is worth stating clearly, because serious tournament Gomoku treats it in a stricter way. Here, a line of six or more stones also wins. This is called an overline, and it counts as a normal win in this game. A long line is hard to build, and it feels wrong to punish a player for making one, so the casual rule is the friendly rule. If the board fills up with no line of five for either side, the game is a draw. Draws are rare, because lines usually break through long before the last crossing is filled.

There are no forbidden moves in this game. Some rule sets for the first player ban certain strong shapes, such as making two open threes at the same time, to balance the first-move edge. This game keeps the classic friendly rules instead. Double threes are legal, double fours are legal, and overlines win. The balance comes from the AI levels rather than from bans, so you can learn the real shapes of the game without a rulebook of exceptions.

To read the board like a strong player, it helps to name the shapes you are looking at. This small table covers the lines that decide games.

Line shape	What it means
Open four	Four stones with both ends open. It cannot be stopped, because one block still leaves the other end free.
Closed four	Four stones with one end open. The defender must block that end at once or lose on the next move.
Open three	Three stones with both ends open. It becomes an open four next turn, so it demands an answer now.
Double three	One stone that makes two open threes at once. The defender can only block one, so the other one grows.
Five or more	The winning line. Six in a row wins too in this game.

The three AI levels

One board, three very different opponents. All three levels play by the same rules. What changes is how far the AI looks and how much it forgives.

Casual is the learning level. This AI takes a winning move the moment one exists, and it blocks any move that would give you five on the spot. Beyond that, it plays in a loose and human way, with a touch of randomness in its choices. It does not study your threes, so a calm line built stone by stone can walk straight past it. New players should start here and stay until they win most games. The first-move edge is real in Gomoku, and Casual lets you feel it.

Skilled judges every crossing by the patterns it makes and the patterns it stops. It values open fours and open threes at their true weight, builds its own lines with intent, and answers your strong shapes with the block that hurts you most. One blind spot remains, and it is a famous one. Skilled rates a crossing by its single strongest line, so a move that quietly makes two open threes at once can slip past it. Find that move and you can beat this level. The strategy section below shows you how.

Master was built to close that blind spot. It scores every pattern on the board, and before it chooses an attacking move it checks whether any of your stones can create two live threats at the same time. If such a crossing exists, Master takes it away at once. It also tests its own best moves against your strongest reply, so a flashy attack that lets you win on the spot never gets played. Be honest with yourself about this level. It is a strong club-style opponent, but it is not a world-class engine, and a patient player with a real plan can still beat it. Wins on Master feel earned because they are.

Level	How it plays	Best for
Casual	Takes wins, blocks five, then plays loose with some randomness	First games and learning the shapes
Skilled	Full pattern scoring, can miss a double three	Regular players who want a real fight
Master	Pattern scoring plus double-threat checks and reply testing	Strong players chasing a win streak

Gomoku or Connect Four?

These two games look like cousins, and players often ask which one to learn. The honest answer is that they test different skills. In Connect Four your pieces fall down a column, so gravity chooses the exact square for you. The board is small, the game is short, and most of the thinking is about the next drop. It is a fine game, and you can play it in the Play Games hub here on GameOLL.

Gomoku gives you the whole board instead. There is no gravity. Any empty crossing on a 15 by 15 grid can hold your stone, which means 225 possible homes on the first move of an empty board. Lines grow in four directions at once, threats stack on top of each other, and a quiet stone placed early can decide the game twenty moves later. If you like games where planning beats reflexes, Gomoku is the deeper water. Most players find the first game takes a little longer, and the tenth game is the one they cannot stop thinking about.

Strategy tips that win games

Take the centre, then stay near the fight. The centre crossing touches more possible lines than any other point on the board. Open there, and keep your next stones within a few crossings of your first ones. Scattered stones make no lines. A tight group makes many lines at once, and lines are what win.

Count the ends, not just the stones. A three with both ends open is worth far more than a four with both ends blocked. Before you place a stone, look at the shape it makes and ask how many open ends it has. Strong players think in open ends. Weak players think in stone counts, and they lose to shapes they never saw.

An open four ends the argument. If you can make four in a row with both ends open, do it, even if it means giving up a smaller plan. Your opponent can block only one end. The other end is your fifth stone. By the same rule, when the AI makes a closed four, the one open end must be blocked that very turn. There is no second chance.

Hunt the double three. The winning idea against Skilled is the double three, one stone that completes two open threes at the same time. Set it up quietly. Build two loose pairs that cross near one empty point, and keep both pairs short so they look harmless. When the crossing stone lands, the AI can block only one line. Extend the other line to an open four, and the game is yours two moves later.

Defend one move earlier than feels natural. Most lost games were lost two moves before the final five. If the AI has an open three, answering it later is the same as not answering it at all, because the four it becomes forces your move and steals your turn. Block threes when they are threes. You will attack again next turn from a live board instead of a lost one.

Use Casual as a training room. New shapes are easier to learn when the punishment is gentle. Practice the double three on Casual until the setup feels automatic, then take it to Skilled. When Skilled starts to feel fair, Master is waiting, and Master does not forgive the same trick twice in one game.

Questions and answers

Is Gomoku free to play here?

Yes. This Gomoku game is completely free to play in your browser. There is no download, no sign-up and no limit on games. Your results and best streak are saved on your own device only.

How do you win a game of Gomoku?

You win by placing five of your stones in one unbroken line. The line can run across a row, down a column or along a diagonal. You play black and move first, and the first side to complete a line of five wins the game.

Does six in a row count in Gomoku?

Yes. In this game a line of six or more stones wins, just like a line of five. This is called an overline. Some strict tournament rules treat an overline differently, but the friendly classic rule is used here, so a longer line is always a win.

Are there forbidden moves in this Gomoku game?

No. This game has no forbidden moves. You can place a stone on any empty crossing, and shapes like the double three are fully legal for both sides. The challenge comes from the three AI levels, not from extra rules.

Can I undo a move?

Yes, on the Casual and Skilled levels. The Undo button takes back a full round, meaning your last stone and the AI reply together. On Master there is no Undo. Every move on Master is final, which is part of what makes that level hard.

What is the difference between Gomoku and Connect Four?

In Connect Four your pieces drop down columns on a small board, so gravity picks the square. In Gomoku you place each stone on any empty crossing of a large 15 by 15 board. Gomoku allows longer plans, more directions and stronger double threats, so most players find it the deeper game.

Last updated: November 7, 2026