How to play
- Take turns dropping a counter into one of the seven columns. It falls to the lowest empty space.
- Get four in a row of your colour: across, up and down, or diagonally.
- Block your opponent when they have three in a row with a space to finish it.
- If the board fills up with no four in a row, the game is a draw.
How strong is the computer?
| Level | How it plays |
|---|---|
| Easy | Looks at its own next move only, and about a third of the time plays a random column. |
| Medium | Looks 3 moves ahead (its move, your reply, its next move). |
| Hard | Looks 6 moves ahead. It always takes a winning move and blocks yours when it sees one. |
When it isn't sure, the computer prefers the middle columns, because a counter there can be part of more lines of four.
Worked example
There are 69 possible lines of four on a 7 × 6 board:
| Direction | Working | Lines |
|---|---|---|
| Across | 4 starting places in each of 6 rows | 24 |
| Up and down | 3 starting places in each of 7 columns | 21 |
| Diagonal (each way) | 12 + 12 | 24 |
| Total | 24 + 21 + 24 | 69 |
A counter in the bottom-middle space is part of 7 of those lines, while a corner counter is part of only 3. That's why the middle column is the strongest place to start.
Tips to win
- Start in the middle column.
- Make two threats at once. If you have two different places that would each finish four, your opponent can only block one.
- Watch the space underneath. Don't drop a counter that lets your opponent play on top of it into a winning space.
Frequently asked questions
Can I play against a friend?
Yes. Choose "2 players" and take turns on the same phone or computer.
Is this Connect 4?
It's the same kind of game, often called four in a row. We wrote our own version from scratch, and it isn't connected with any other company's game.
Can I play with a keyboard?
Yes. Use Tab to reach the arrow buttons above each column and press Enter to drop a counter there.