Connect 4 Winning Rules: Diagonals, Multiple Lines & Full Grid
In Connect 4, a winning line contains four of your own discs in a straight uninterrupted row.
Horizontal wins
Four matching discs side by side on the same row win immediately.
Vertical wins
Four matching discs stacked in one column also win.
Diagonal wins
A straight diagonal of four matching discs counts in either diagonal direction. Hasbro’s instructions explicitly list diagonal lines as a standard way to win.
Can one move make two winning lines?
Yes. A newly dropped disc can complete more than one four-in-a-row at the same time. The game is already won as soon as the move completes a legal line.
What if the grid fills?
If all 42 spaces fill without either player making four in a row, no player has achieved the stated win condition; reset and play again.
Related guides
Complete Connect 4 rules · Strategy · Game hub