Connect Four
Drop chips to connect four in a row - vs a smart AI or a friend on one screen
100% free. Runs entirely in your browser - your files and data never leave your device and nothing is uploaded to any server.
Your turn - drop a red chip
Picking the other player's colour swaps the two. Saved on this device.
- Click a column to drop your disc - it falls to the lowest free hole.
- Line up four across, down or diagonally to win.
- Keyboard: Tab to a column, then Enter or Space.
About this tool
Drop chips into columns to connect four in a row - horizontally, vertically, or diagonally - against a smart AI or a friend sharing the same screen. A classic strategy game that's simple to learn but has real depth for skilled play.
How to use this tool
- Choose opponentPlay vs AI difficulty level or local second player.
- Control board centerUse central columns for stronger offensive options.
- Build and block threatsCreate your own lines while preventing opponent chains.
- Convert winning setupForce unavoidable four-in-a-row finish.
How to play Connect 4
Players take turns dropping a disc into one of the seven columns; it falls to the lowest empty space. The first to line up four of their discs in a row - horizontally, vertically or diagonally - wins. If the board fills up with no line of four, the game is a draw.
Play the computer at easy, medium or hard, or play a friend on one screen. Against the computer, take the centre column early, block any three-in-a-row immediately, and look for moves that create two threats at once - your opponent can only block one of them.
Key features
- Trains foresight and counterplay decision-making.
- Simple rules with deep tactical outcomes.
- Great local strategy duel format.
- Replayable against varying AI levels.
Common uses
- Quick strategy matches with friends.
- Practicing tactical planning skills.
- Teaching turn-based game logic.
- Solo progression against stronger AI.
Tips for better results
- Think one move ahead for both sides.
- Prioritize center control early.
- Look for double-threat opportunities.
- Block immediate losing threats first.
Mistakes to avoid
- Playing only attack with no defense.
- Missing diagonal opportunities and threats.
- Dropping pieces into trap columns.
- Ignoring opponent forced-win patterns.
Frequently asked questions
Multiple difficulty levels are typically available, letting you choose an easier AI while learning strategy, or a genuinely tough opponent once you've gotten comfortable with the game.
Yes - two-player mode lets you and a friend take turns dropping chips on the same device.
Yes - stats like win streak and overall record are typically saved locally, so you can track your performance over multiple games.
The centre column is part of more possible four-in-a-rows than any other, so pieces there create the most threats. Strong players usually start in the middle.
Create two threats at once, so your opponent can only block one. Another trick is to build a threat on a row your opponent cannot play under without giving you the winning square.
Yes - Connect Four was solved in 1988, and with perfect play the first player wins by starting in the centre column. Against a person, that perfect line is almost impossible to follow, which keeps games interesting.