FreeCell

Goal of the game

Build the four suits up on the foundations, from Ace to King. Every card is visible: it is a pure logic problem.

How it works

• Eight columns; you build down by one rank, alternating red and black.
• Each free cell (top left) holds one card, any card.
• An empty column accepts any card or sequence.
• An ordered sequence can be moved as a block if there is enough room: up to (free cells + 1) × 2 to the power of (empty columns) cards, half as many if the destination is itself an empty column.
• Cards that are no longer of any use head to the foundations on their own.

Controls

• Drag and drop a card or a sequence.
• Tap: the card goes to the best place (foundation, column, then cell).
• Double-tap: to the foundation.
• Ctrl+Z to undo, I for a hint.

Numbered deals

The deal number (1 to 1,000,000) follows the classic numbering: deal no. 1 is the same everywhere. Tap the number to replay a deal or pick another one.

About the solver

The solver explores positions in a separate thread using a best-first search guided by a heuristic (cards remaining, depth of the next useful cards, broken sequences, occupied cells, empty columns). A deal’s difficulty is measured by the number of positions it has to examine: the more it searches, the trickier the deal. At the Devilish level, the deal is verified as winnable with only three cells. The “AI solves” button replays its solution before your eyes; a game solved by the AI does not count towards your records.