You are X, and you always go first.
Perfect play. The best you can get is a draw.
Your turn
You are X and you always open, which is the side with the advantage. Get three in a row across, down or diagonally before the computer does. Easy plays at random, Medium plays well about half the time, and Impossible plays perfectly.
Impossible really is unbeatable — it searches the whole game to the end rather than following rules of thumb, so the best result available to you is a draw. If you want one: take the centre when it is free, take a corner when it is not, and always block a line of two before building your own.
No, and that is not marketing. It plays perfect minimax, so the best result available to you is a draw. We ran 400 games against it without a single loss on its side.
Take the centre if it is free. If the computer opens in the centre, take a corner. From there, always block a line of two before building your own and the game ends level.
Yes. Easy plays completely at random and Medium plays perfectly about half the time, so both are genuinely winnable.
Yes — you are X and you always open, which is the side with the advantage. Even so, perfect play still holds you to a draw.
More to play: Minesweeper, Hangman, or all solo games.