You 0
CPU 0
Draws 0
Score 0
You are red — pick a column.
Drop discs. Line up four. Win.
Computer difficulty
Connect Four is a classic two-player connection game played on a 7-column by 6-row vertical grid. You play the red discs against the computer's yellow. Click or tap any column and your disc drops to the lowest empty slot in that column. Take turns with the AI until one side lines up four discs in a row — horizontally, vertically, or diagonally — or the board fills up for a draw. The computer comes in three difficulty levels: Easy takes wins and usually blocks yours but otherwise plays loosely, Medium looks one move ahead and punishes blunders without setting traps, and Hard uses a deeper lookahead search that spots your threats early and builds attacks of its own — tough, but beatable with good play. Your last choice is remembered for next time. Wins are scored by level — one point on Easy, two on Medium, three on Hard — so your session score and leaderboard posts reflect who you actually beat.
Strategy tips for winning at Connect Four: control the center column. Discs in the middle participate in more possible four-in-a-row lines than discs on the edges, so a strong opening is to drop your first piece dead center. Watch for "double threats" — positions where you have two ways to complete four in a row at once, because your opponent can only block one. Think one move ahead before you drop: never place a disc that gives the computer a landing spot to complete its own line directly above your move. Odd and even row threats matter too — as red (moving first), threats on odd rows tend to pay off in the endgame. Line up your discs, trap the AI, and claim the win.
Prefer a human opponent? Switch to the 2 Players mode to play 2 player Connect Four online with a friend on the same device. It's classic pass-and-play: red and yellow take turns tapping columns on one screen — perfect for a quick head-to-head match with no accounts, downloads, or second device needed.
Friend not in the room? Choose Play by Link for correspondence Connect Four: make your move, then send the generated link by text, email, or chat. The whole board travels inside the link — no accounts, downloads, or servers — and when your friend moves, they send a link back to you. A game can unfold over minutes or days, one move at a time.
Want live turns instead? Choose Play with Friend: you get one shareable room link, both of you stay on the page, and the board updates automatically as each person drops a disc — no need to send a new link after every move. Play by Link still works when you prefer slow, send-each-move correspondence.