The Deal Lab makes the deal system transparent. Every deal number recreates the same starting cards, so two players can compare the same challenge without an account. Choose Draw 1 or Draw 3, inspect the opening layout, and send the permanent link to another player.
What “verified winnable” means here
A verified-winnable deal is constructed with a complete legal route for all 52 cards to reach the foundations. It still uses a standard 52-card deck, the usual seven tableau columns containing 28 cards, and a 24-card stock. The deal number changes the suit interleaving, column allocation, and stock sequence while preserving a solution certificate.
This is deliberately different from labelling an ordinary shuffle “winnable” after a weak heuristic. The certificate checks that every next card is the correct rank for its suit, that a tableau card is exposed before it is played, and that the Draw 1 or Draw 3 stock order exposes stock cards in the promised sequence.
Random deals and honest limits
Random numbered deals use a deterministic seeded shuffle. They are reproducible, but the site does not claim that every random deal is solvable. Klondike can contain forced losses, and proving an arbitrary position solvable requires a much broader search than a hint system.
The automated test suite validates the construction against 100 different deal numbers in both Draw 1 and Draw 3 modes. That is 200 complete 52-card certificates plus layout and uniqueness checks. The construction itself applies the same invariants to every supported deal number from 1 through 999,999,999.
How to use a deal number
Enter any number from 1 to 999,999,999. The same number, mode, and draw rule always produce the same opening position. “Play this deal” opens it on the main Solitaire page. A shared link includes all three settings, so the recipient does not have to configure anything manually.
The downloadable JSON record is generated locally in your browser. It contains the selected settings, opening layout, stock order, and—only for verified-winnable deals—the complete solution-card sequence. No game or account data is uploaded.