Connect4.io

Connect 4 Online

First to connect four discs wins.

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How to Play

Drop discs into the board, build a line of four, and block your opponent before they finish their pattern.

1

Drop

Basic move

Pick a column. The disc falls to the lowest open slot in that column.

  • You cannot place a disc in the middle of the board.
  • A full column cannot accept another move.
2

Connect Four

Winning pattern

Line up four matching discs horizontally or vertically.

  • Horizontal wins usually happen near the bottom rows.
  • Vertical wins happen when one column is left unblocked.
3

Block

Defense

Watch the next threat. If your opponent has three, block the fourth slot.

  • Block before building your own attack if the opponent can win next.
  • The highlighted slot stops the yellow vertical threat.
4

Diagonal Win

Advanced win

Build from the bottom upward to create a diagonal four-disc path.

  • Diagonal wins need support discs underneath each step.
  • They are harder to notice, so scan both diagonal directions.

Rules

  • Player 1 uses red discs and Player 2 uses yellow discs.
  • Players take turns dropping one disc into any open column.
  • A disc always falls to the lowest empty slot in the selected column.
  • If the board fills without a winner, the match ends as a draw.

Winning Patterns

Horizontal

Four matching discs in one line.

Vertical

Four matching discs in one line.

Diagonal

Four matching discs in one line.