Discs fall down — line up four
Connect 4 online
Play Connect 4 online with a friend or against a bot. Drop discs into columns, line up four in a row, and win — straight in your browser.
Join with a code
Lethal Card · Every game against a person counts toward your Lethal Card — one ELO for every game.
Connect 4 looks like a children’s game but it is a solved one: the first player wins by opening in the middle column and never slipping. That single fact makes the centre the most valuable real estate on the board.
Players2 players
Game length3 minutes
How to play
- The board has seven columns and six rows.
- You pick a column and your disc falls to the lowest empty slot.
- The first player to line up four discs — across, down, or diagonally — wins.
- If the board fills with no line, the game is a draw.
Strategy
- Take the centre column. More winning lines pass through it than through any other.
- Count parity: odd-row threats favour the first player, even-row threats the second.
- Never play directly under a square where your opponent completes four. You are handing it over.
- Stack two threats vertically. They block the lower one and the upper one wins.
Frequently asked
Who wins Connect 4 with perfect play?
The first player, provided they open in the centre column. The game was solved in 1988; any other opening gives the second player a draw or a win.
Why does the centre column matter so much?
Seven possible fours run through it, against three through an outer column. A centre disc is worth more than twice an edge disc.
How strong is the bot?
On Hard it searches eight plies deep with alpha-beta pruning. Beating it without understanding parity is genuinely difficult.
All games
Battleship Extreme
Battleship with superweapons: nukes, torpedoes, radar
Prisoner and Guard
Escape a dark maze: one player looks for the way out, the other hunts them
Battleship Blitz
A small 6 × 6 grid, three ships, a game in minutes
Connect 4 Pop Out
Connect 4 where you can pull a disc out from the bottom
Chess
The full rules, no shortcuts
Ultimate Tic Tac Toe
Nine boards inside one
Tic Tac Toe
Three in a row on a 3×3 grid
Battleship
Find their fleet and sink it first
Maze Race
Cross the board, or wall them in
Gomoku
Five in a row on a 15×15 board
Checkers
Captures are compulsory
Reversi
Flip their discs, own the corners
Hex
Connect your sides, no draws
Nine Men's Morris
Three in a row takes a piece
Mancala
Sow the seeds, fill your store
Master and Students
The card you play goes to them
Backgammon
A race for fifteen checkers, dice deal the cards
Ludo
Four tokens home, and rivals back to the start
Dots and Boxes
Join dots, close boxes
Would You Rather
Two bad options, one choice
Never Have I Ever
Confess, or bluff
Most Likely To
Vote for who would do it
Truth or Dare
One asked, the rest judge
Story Chain
Everyone adds a line