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How to Play Pente

Pente is played on a 19x19 grid. You place the light stones and move first; the AI answers with dark stones, one per turn, on any empty intersection. There are two ways to win: line up five or more stones in a row horizontally, vertically or diagonally, or capture ten enemy stones. A capture happens when your new stone and one of your existing stones sandwich exactly two enemy stones in a straight line — those two are lifted off the board.

The counters above the board show captured stones, not pairs, so the target is 10. Captures work in all eight directions and a single stone can take more than one pair at once. Only the player who moves captures, so placing your stone into a gap between two enemy stones is always safe. If the board fills with no winner, the game is a draw. Choosing a difficulty starts a fresh game straight away.

Strategy Tips

Pairs are targets - exactly two stones in a line can be captured. Before you make a pair, check whether an enemy stone already sits at one end.
Prefer split shapes - X_X cannot be captured along its line, and filling the gap later turns it into a solid three.
Break lines by capturing - taking a pair that includes one stone of an enemy four removes that stone and kills the threat without a block.
Watch the capture count - once a player has eight stones, every capture threat is a threat to win and must be answered like a four.
Combine the two win conditions - a stone that makes a three and threatens a capture at the same time gives your opponent two problems and one move.

Read the full Pente guide →

Playing Pente on PlayVersusAI

Pente on the full 19x19 board: five in a row wins, and so does capturing ten of your opponent's stones. A capture is made by flanking exactly two enemy stones in a line with your new stone at one end and an existing stone at the other, in any of the eight directions. You play the light stones and always move first, the opening is unrestricted, and the counters above the board track captured stones rather than pairs, so the race is to 10.

On every level the AI checks three things in order. If it can win at once, by making five or by taking the pair that brings it to ten captured stones, it does so, even when you also have a four on the board. If you are threatening to win next move, it picks the reply that leaves you the fewest winning points, which may be a block or a capture that breaks your line. Otherwise it judges the position: open and blocked twos, threes and fours, split shapes, double threats, captures, capture threats against either side's pairs, and the danger of making a pair that can be bracketed.

What's on This Page

Four difficulty levels — Easy, Medium, Hard and AI Training, chosen with the buttons above the board. Changing level starts a fresh game.
Tracked results — wins count toward your profile statistics and the site leaderboard.
No account required — the full game is playable as a guest, on desktop, tablet or phone.

Easy always takes a win and stops an immediate loss, but it weighs your other threats at half strength and adds heavy randomness, so open threes and loose pairs often get past it. Medium uses the full one-move evaluation with almost no randomness: it blocks open threes, protects pairs you are threatening and punishes pairs you leave beside its stones. Hard adds an alpha-beta search, usually three to six moves deep over its dozen most promising candidates, within about a second per move, so it sets up double threats and capture combinations and sees yours before they land. AI Training runs the same search with no randomness but keeps deepening it for up to about 1.2 seconds per move, and when time runs out mid-iteration it still uses the deeper result if its first choice was fully checked. In 72 test games against Hard from varied openings it won 50 and lost 22. Choosing any level starts a fresh game.

Mistakes That Lose Games

Extending a lone stone into a pair right next to an enemy stone. That is the O X X _ pattern, and it hands your opponent a capture the moment they play the empty end.
Blocking with a stone that forms a pair. If your blocking stone and one of your earlier stones can be bracketed, capturing them removes the block and reopens the line you just stopped.
Looking for line threats only along the line. A four can be broken from the side by capturing a pair that crosses it, so check every pair that contains one of its stones.
Losing track of the capture count. At eight captured stones, one more pair ends the game, and a capture threat that looked minor at two stones becomes as urgent as a four.

Pente Questions

Do captures count as pairs or as stones?

As stones. Each capture removes two stones and adds two to your counter, and the game ends the moment either side reaches 10 — five captures in total. A single placement that flanks two pairs at once adds four.

Can I place a stone between two of the AI's stones?

Yes, and it is safe. Only the player making the move captures, so a stone you place to complete the pattern enemy, you, you, enemy stays on the board. The same applies to the AI.

Is the tournament opening rule used?

No. Tournament Pente makes the first player start on the centre point and place their second stone at least three intersections away from it. This version lets you open anywhere, so the first-move advantage is entirely yours to use.

For the complete rules, the deeper strategy and the history of the game, read the full Pente guide, or browse guides for all 33 games.