How to Play Tic Tac Toe
Tic Tac Toe — noughts and crosses in the UK — is the simplest strategy game there is: two players, a 3×3 grid, and a race to make three in a row. It takes seconds to learn, but there's real strategy in never losing.
By the Multiplayer Games team · Updated · Rules checked against the sources below
Objective
Be the first to place three of your marks in a straight line: across, down or diagonally.
Setup
The board is an empty 3×3 grid. One player is X, the other is O, and X usually goes first.
Tic Tac Toe rules, step by step
- Take turns. Players alternate placing one mark in any empty square.
- Make a line. Three of your marks in a row, column or diagonal wins immediately.
- Block threats. If your opponent has two in a line with the third square open, you must block it or lose.
- Draws. If all nine squares fill with no line, the game is a draw.
Tic Tac Toe variants, and the rules we use
Tic Tac Toe is played slightly differently from place to place. These are the variants you're most likely to meet:
- Ultimate tic-tac-toe. Nine small boards inside a big one; where you play decides which board your opponent must play in next.
- Misère. Whoever makes three in a row loses.
- Bigger boards. 4×4 or 5×5 boards needing four in a row lead towards Gomoku.
How Tic Tac Toe works in Multiplayer Games:
- Standard 3×3 rules.
- The first move alternates between rounds in a series, so neither player keeps the advantage.
- The computer's Hard level plays perfectly — the best you can do is draw.
Tic Tac Toe strategy for beginners
- Going first, take a corner: it gives your opponent the most ways to go wrong.
- If your opponent takes a corner first, answer in the centre.
- Aim for a fork — a move that makes two threats at once so only one can be blocked.
- With perfect play from both sides, Tic Tac Toe is always a draw; wins come from your opponent's mistakes.
Common mistakes to avoid
- Answering a corner opening with an edge square, which hands the first player a fork.
- Chasing your own line and missing your opponent's two-in-a-row.
Tic Tac Toe terms explained
- Fork
- A move that creates two winning threats at once.
- Block
- Placing your mark to stop your opponent's line.
- Solved game
- A game whose result with perfect play is known.
A short history of Tic Tac Toe
Three-in-a-row games on a grid go back thousands of years; the Romans played a version called terni lapilli with movable counters. The pencil-and-paper game became known as noughts and crosses in Britain and tic-tac-toe in America.
In 1952 A. S. Douglas wrote OXO, a noughts-and-crosses program for the EDSAC computer at Cambridge — one of the earliest video games. Because there are only a few thousand distinct positions, tic-tac-toe is fully solved: with perfect play from both sides it's always a draw.
Tic Tac Toe FAQ
Sources
We checked these rules against:
