Tic-Tac-Toe Strategy: How to Never Lose a Game

Why Tic-Tac-Toe is a “solved” game

Tic-Tac-Toe has only 255,168 possible games, small enough that computers mapped every one of them decades ago. The result: if both players make no mistakes, every game ends in a draw. That sounds boring, but it is actually great news — it means that if you learn a handful of patterns you will never lose, and you will win every time your opponent slips.

On DashLink, X always moves first and the server checks every move, so you can focus entirely on strategy. To follow this guide, number the squares like a phone keypad: 1-2-3 across the top, 4-5-6 in the middle and 7-8-9 at the bottom. Square 5 is the centre, 1, 3, 7 and 9 are corners, and 2, 4, 6 and 8 are edges.

The three priorities on every turn

Before every move, run through this checklist in order. It sounds simple, but most lost games come from skipping step two.

• Win: if you have two in a line and the third square is empty, take it.
• Block: if your opponent has two in a line with the third square empty, take that square — even if you had a clever plan.
• Build: otherwise, make a move that creates a fork (two winning threats at once) or prevents your opponent from making one.

Playing first as X

The strongest practical first move is a corner. The centre is also perfectly safe, but a corner gives your opponent the most ways to go wrong. Of the seven replies O can make to a corner opening, only one — taking the centre — avoids a forced loss.

Example: you play 1. If O answers with an edge such as 2, play 5 (the centre). Now you threaten 9 to complete the 1-5-9 diagonal, so O must block at 9. Take 7: you now threaten both 4 (the 1-4-7 column) and 3 (the 3-5-7 diagonal). O can only block one of them, and you win on the next move. That double threat is called a fork, and it is the only way to beat a careful opponent.

If O correctly takes the centre after your corner, take the opposite corner (9). Many players now panic and play a corner, which lets you fork. If they play an edge, simply keep blocking and the game will be drawn.

Playing second as O

As O your goal is first not to lose. Use this rule: if X opens in a corner, take the centre. If X opens in the centre, take a corner. If X opens on an edge, take the centre or the corner next to their mark.

The most common trap for O is the “opposite corners” position: X has 1 and 9, O has 5. Your instinct says to take another corner, but that hands X a fork. The correct move is an edge (2, 4, 6 or 8), which forces X to block you and kills every fork. Remember: when X holds two opposite corners, O plays an edge.

Spotting forks before they happen

A fork almost always uses a corner that sits on two lines your opponent already partly controls. Before you move, look at every empty corner and ask: “If my opponent took this square, would they threaten two lines at once?” If the answer is yes, either take that square yourself or make a move that forces them to respond somewhere else.

Forcing moves are your best defensive tool. If you create a two-in-a-row, your opponent must block it, and you get to choose where their mark goes. Good players use forcing moves to steer the opponent’s marks into squares where they cannot fork.

Practising on DashLink

Open Tic-Tac-Toe from the games list, create a room and share the room code with a friend, or use “Find Players” to see who else is looking for a match. Wins add to your score on the global and per-game leaderboards, so every fork you land counts. Try playing ten games as X using only corner openings, then ten as O using the edge-defence rule — you will feel the difference immediately.