Gomoku

How to play Gomoku (Five in a Row)

Gomoku, also called Five in a Row, is one of the world’s oldest and most popular strategy board games, played for centuries across East Asia. Two players take turns placing black and white stones on a 15×15 board, each trying to be the first to line up five of their own stones in an unbroken row. The rules take less than a minute to learn, but the tactics — open threes, double threats and forcing sequences — give the game surprising depth. Play a friend on the same screen, or challenge the computer at three difficulty levels and earn ranking points for every win.

The goal

Be the first player to form an unbroken line of five (or more) of your own stones. The line may run horizontally, vertically, or diagonally in either direction. Black always places the first stone, then the players alternate. If every intersection is filled and neither player has made five in a row, the game ends in a draw.

The board and the stones

The game is played on a 15×15 grid, the standard tournament size for Gomoku. Stones are placed on the intersections and never move again: there is no capturing, no jumping and no removal. Once a stone is on the board it stays there for the rest of the game, so every move permanently shapes the position. The stone placed most recently is marked with a small amber dot, so both players can always see where the game left off.

Rules of play

• Black moves first and places a single stone on any empty intersection. The opening stone is traditionally played at or near the centre point, which gives the first player the most room to build in every direction.
• Players then alternate turns, placing exactly one stone of their own colour per turn on any empty intersection. You may never place a stone on an occupied point, skip a turn, or move a stone that has already been played.
• Stones are never captured or removed. The board only fills up as the game goes on, so think of every stone as a permanent claim on that point.
• The first player to complete an unbroken row of five of their own stones — horizontally, vertically or diagonally — wins immediately, and the winning line is highlighted.
• This version uses the classic “free-style” rule: a line of six or more stones (an “overline”) also counts as a win, and there are no extra restrictions on Black. (Tournament variants such as Renju forbid overlines and certain double threats for Black — those rules are not used here.)

Winning and draws

The game ends the instant a player completes five or more in a row — the winning stones glow on the board. Because stones are never removed, a game can also end with the whole 15×15 board full and no line of five anywhere; that game is a draw. In practice draws are rare: with 225 intersections there is almost always a decisive threat long before the board fills. In the two-player game you can use the Undo button to take back the last stone if a finger slips.

Playing the computer (ranked)

In “Gomoku vs Computer” you choose your colour and one of three difficulty levels. Easy plays loosely and makes deliberate mistakes, so beginners can win. Normal looks ahead and punishes obvious errors. Expert searches deeper, blocks your fours and rarely misses its own winning line. The computer thinks entirely on your device, so it works offline. Beat it to earn ranking points — Easy +10, Normal +30, Expert +100 — and sign in to put your best result on the leaderboard.

Strategy tips

• Play your opening moves near the centre. A stone in the middle of the board can be part of lines in every direction, while a stone near the edge has far fewer ways to grow into five.
• Learn to spot the “open three” — three stones in a row with both ends empty. Left alone it becomes an open four, which threatens five at both ends and cannot be stopped. Block enemy open threes at once, and build your own whenever you can.
• Win with double threats. A single threat can always be blocked, so strong players aim to create two threats with one stone — for example a four and an open three at the same time, or two open threes crossing at one point. Your opponent can only answer one of them.
• Don’t just chase your own lines — the best moves attack and defend at once. A stone that extends your row while cutting through the opponent’s formation is worth two ordinary moves.
• When you are forced to defend, choose the blocking point that also helps your own shape. There are usually two ends you could block; pick the one that sits next to your stones or claims useful space in the centre.

Frequently asked questions