Four in a Row

🕹️ How to play

1. How to start a game: The page opens straight into a two-player game on one screen — no start button, no account. The bar above the board says "Round 1 · Red to move" and a red disc sways above column 4. Tap anywhere in a column (top, middle or bottom all count) and the disc falls to the lowest empty spot.
2. How to win Four in a Row: Line up four of your discs across, down or diagonally before your opponent does; five or more also counts. The winning discs light up with a glowing outline and a line through them, the rest dim, and the result card appears below the board so it never hides how the game was won.
3. Playing two players on one phone: Lay the phone flat on the table and take turns tapping columns. After each move the turn bar switches colour and name, and a short input lock stops a double tap from playing your opponent's move. Tap Play again after each round — the other player starts next, and the score keeps adding up.
4. Playing against the computer: Switch the mode to vs computer at the top; it starts on Casual with alternating first move. Settings offer four levels: Beginner plays loosely, Casual blocks threes but sometimes misses a diagonal, Strong almost never misses a block, and Master looks far ahead but is not a perfect solver, so it can still be beaten. Each level keeps its own win/loss record.

📖 Rules & variants

Board and drops: the standard Four in a Row grid stands upright with 7 columns and 6 rows — 42 spaces. Players take turns choosing a column; the disc falls under gravity to the lowest empty space. You pick a column, never a square, so a space can only be filled once everything below it is filled.

Winning and draws: the first player to get four or more discs in a row horizontally, vertically or diagonally wins. If all 42 spaces fill up without a four, the game is a draw. A full column cannot take another disc — the page says so and the turn does not change. When one move completes two lines at once, both are highlighted and the result reads "double four".

First move and score: the standard 7×6 game was solved by computer in 1988 — the first player can always force a win by starting in the centre column and playing perfectly afterwards. That is why the first move alternates every round here: Red starts odd rounds, Yellow starts even rounds. Against the computer you can alternate, always go first, or let the computer start. A round is scored once, at the winning move, so reloading never counts it twice.

Undo and replay: in two-player mode Undo takes back one move; against the computer it takes back your move and the computer's reply, or just your move if the computer is still thinking. The computer's opening move cannot be undone. Once a round is over, Undo becomes Replay so you can step through the game move by move.

Example (a missed diagonal): Red starts and the columns played are 4 5 5 6 6 7 6 7 7 1 7. After move 7 Red has a diagonal three from column 4 row 1 to column 6 row 3; move 9 fills column 7 up to row 3, so column 7 row 4 becomes a live threat. Yellow plays column 1 instead of blocking, and Red drops into column 7 for a diagonal four.

Four in a Row strategy: take the centre column early — more lines pass through it than any other; block an open three as soon as its fourth space is playable; never drop directly under your opponent's winning space, because that props it up for them; and aim for two winning spaces at once, since your opponent can only block one. Stronger players also track odd and even rows for the endgame.

Connect 4 examples

❓ FAQ