1. Enter moves
Click the columns in the same order they were played. Use Undo and Redo if you need to fix a position.
Solver guide
How to use the Connect 4 solver
The calculator works best when you enter the position exactly as it happened. Add each move in order, choose the player you want to analyze, and compare the recommended column with the threats on the board.
Open the solver2. Pick a target
Analyze the current player, Red, or Yellow. This helps when you are studying a position from one side's point of view.
3. Read the result
The highlighted column is the recommended move. A + or − number marks a proven win or loss in that many turns. A ~ is a search estimate, not a proven draw. Check whether the move blocks a threat, creates a fork, or improves center control.
What to study after the result
In Practice vs AI, you play Red and the AI plays Yellow. Undo and Redo step through a full turn, including the AI reply when available. Master attempts a full proof within a time budget, then uses deeper search if the outcome remains unproven.
Try columns 4, 1, 4, 1, 4, 2. Red has three discs stacked in the center and can win in column 4. Check that the recommendation completes that line. Look for immediate wins, forced blocks, diagonal support, and moves that create two winning threats on the next turn.