🔴 Connect Four
Drop discs, build a line of four, block the AI doing the same.
AI
STATUS 0W/L/D 0
How to play Connect Four
- Choose a column to drop your disc into.
- Discs stack from the bottom up.
- Line up four of your colour horizontally, vertically or diagonally to win.
- The AI is trying to do exactly the same thing while blocking you.
Controls
| Input | Action |
|---|---|
| Click / Tap a column | Drop a disc |
| 1 to 7 keys | Drop by keyboard |
| R | New game |
| F | Enter or leave full screen |
| Esc | Leave full screen |
Tips & strategy
- The centre column is the strongest opening because it belongs to the most possible lines.
- Count threats before you play — a move that creates two threats at once wins.
- Watch for the AI building a diagonal; they are the easiest to miss.
- Avoid playing directly beneath a square that would complete your opponent's line.
Frequently asked questions
How strong is the AI?
Hard uses a minimax search several moves deep with alpha-beta pruning, so it will punish careless play, though it is not perfect.
Who moves first?
You do, playing red. Going first is a genuine advantage in Connect Four.
Does board size change?
No, it is the standard seven columns by six rows.