How the Minimax Algorithm Makes Tic Tac Toe Unbeatable
Ever wonder why our Tic Tac Toe AI never loses? Here's the clever algorithm powering it — explained simply.
What is Minimax?
Minimax is a decision-making algorithm used in two-player games. It works by simulating every possible future move, assigning scores to outcomes, and always choosing the move that maximises the AI's advantage while minimising yours.
How It Works in Tic Tac Toe
At each turn, the AI builds a complete game tree — every possible move, for every possible counter-move, all the way to the end. A win for the AI scores +10, a loss scores -10, and a draw scores 0.
The AI then picks the branch that guarantees the highest minimum score — hence minimax.
Why It's Unbeatable
Because Tic Tac Toe has only 9 squares and a finite number of game states, the AI can evaluate every single possibility in milliseconds. There is no move you can make that it hasn't already considered.
Can You Ever Win?
Against a perfect Minimax AI: no. The best outcome you can achieve is a draw — and only if you also play perfectly. Start in a corner for your best shot at forcing a draw!
