Ultimate tic tac toe online, free
Ultimate tic tac toe takes the game everyone knows and puts nine copies of it inside one big board. You still draw X and O and still try to get three in a row, but every move does two jobs: it claims a cell, and it decides where your opponent has to play next. That one rule turns a game children solve in an afternoon into a real strategy game.
Here you can play ultimate tic tac toe online against the computer on Easy, Medium or Hard, or choose 2 players and pass one phone, tablet or computer back and forth. No download and no account. Against the computer you play X in the first game, and you switch between X and O every game, so you practise moving first and moving second.
How to play here
Tap or click an empty cell inside a glowing board. The boards you are allowed to play in glow gold; the others dim a little, so you can see the send rule at work without counting cells. On the first move every board glows, because X may start anywhere.
Your mark draws itself in, and the board it points to starts glowing for the other player. When a small board is won, a short line marks the three in a row and a big X or O fills the board. A small dot in the corner of a cell marks the last move, which helps you spot the computer’s reply. When someone takes three boards in a row, a gold line runs across the whole grid.
The two chips at the top show who is X and who is O, and how many small boards each side has won. The chip of the player to move lights up. Undo takes back your last move, together with the computer’s answer. Hint asks the hard computer for its choice and lights that cell. Restart deals a fresh board with the same settings, and the pause menu lets you change the opponent or the level. With a keyboard, use the arrow keys to move around the 81 cells and Enter to play.
The send rule, step by step
Picture each small board as a mini map of the big one. Its top-left cell matches the top-left board, its centre cell matches the centre board, and so on. If you play in the bottom-left cell of any small board, your opponent must play their next move somewhere in the bottom-left board.
When the matching board is already won or completely full, your opponent is not stuck. They get a free move and may play in any open board. This is the standard rule, and it matters a lot in the late game, when free moves become the most powerful thing you can give away. Drawn small boards stay on the grid but count for neither player, so a line of three boards needs three boards won by the same side.
Strategy that works
- Read the board you send them to. Before every move, check the small board your cell points at. If your opponent can win it in one move, find another cell.
- Take the centre board seriously. It is part of four lines on the big grid. Corners are part of three, edges only two.
- Don’t chase every small board. Winning a board that sits on no useful line can cost you tempo elsewhere. Think about which boards help you make three in a row.
- Plan two moves out. Your move sends them somewhere, and their move sends you somewhere. Try to choose cells so that their likely reply sends you back to a board you want.
- Keep free moves for yourself. Avoid sending your opponent to a closed board late in the game, and try to make them do it to you.
A short history
Games of tic tac toe inside tic tac toe have been played on paper for a long time under names like super tic tac toe and meta tic tac toe. The game spread widely after math teacher Ben Orlin wrote about it in 2013 on his blog Math with Bad Drawings, calling it ultimate tic tac toe. Since then it has become a favourite in classrooms and among programmers, who use it to test game-playing programs.
Levels and more games
Easy is for learning the send rule. Medium punishes careless sends. Hard looks deep and rarely gives anything away, so you will need to set up two threats at once to beat it. For more games on a grid, try Four in a Row, Gomoku for five in a row on a big board, or Football Tic-Tac-Toe if you want to test your football knowledge with a friend.
How to play Ultimate Tic Tac Toe
- The big board is a 3×3 grid of nine small tic tac toe boards. X moves first and may play in any cell of any small board.
- The cell you play in sends your opponent to the matching small board. Play in the top-right cell of a small board, and your opponent must play next in the top-right small board.
- Three of your marks in a row inside a small board wins that board. A big X or O then fills it.
- If you are sent to a board that is already won or full, you may play in any open board. This is the standard rule, and the glowing boards always show where you can play.
- A small board that fills up with no three in a row is drawn and counts for nobody.
- Win three small boards in a row, across, down or diagonally, to win the game. If every board is decided and nobody has three in a row, the game is a draw.
Ultimate Tic Tac Toe tips
Watch where you send your opponent
Every move is also a choice of where the other player goes next. Before you play, look at the board your cell points to. If your opponent has two in a row there, you are handing them a small board.
Control the centre board
The centre board sits on four lines of the big grid, more than any other. Winning it early gives you many ways to make three in a row, so fight for it and avoid sending your opponent there when they are close to taking it.
Avoid giving free moves late
Sending your opponent to a board that is already decided lets them play anywhere. Early on that rarely matters. Late in the game a free move often lets them finish a line of boards, so keep your moves pointing at open boards.
Think in pairs of threats
One threat inside a small board is easy to block, but your opponent can only be in one board at a time. Build two in a row in several boards, and the board you send them to cannot cover the others.
Frequently asked questions
How do you play ultimate tic tac toe?
You play tic tac toe on nine small boards arranged in a big 3×3 grid. The cell you choose inside a small board tells your opponent which small board they must play in next. Win a small board with three in a row, and win the game by taking three small boards in a row.
What happens if you're sent to a full board?
Under the standard rule, used here, you may play in any small board that is still open. The same goes for a board that someone has already won. Some groups play a stricter version, but the free move is the common one.
Is ultimate tic tac toe solved?
Not the standard version played here, as far as we know. Plain tic tac toe is a draw with perfect play, but ultimate tic tac toe has far more positions, and no one has published a proof of who wins with perfect play under these rules. Strong computer programs exist, and some rule variants have been studied more closely, so if you read that it is solved, check which rules are meant.
Is super tic tac toe the same game?
Usually, yes. Super tic tac toe, meta tic tac toe, tic tac toe 9 boards and strategic tic tac toe are common names for the same game of nine small boards inside a big one. Small rule differences exist, mostly about what happens when you are sent to a closed board.
How strong is the computer?
Easy plays mostly at random but never misses a move that wins a small board, so it suits learning the send rule. Medium thinks a little ahead. Hard runs a few thousand simulated games before each move, and you need to plan where you send it to win.
