Solitaire Double: what a two-pack deal gives you to work with
Solitaire Double is Klondike played with two packs shuffled together: 104 cards, nine columns and eight foundations. It sounds twice as hard. In our study it turned out to be far kinder than ordinary Klondike. A simple computer player that sees only the face-up cards and never undoes a move won 81.5% of 10,000 deals, against 42.3% in single-pack Klondike with the same one-card turn.
The reason is in the deal. With two cards of every rank and suit, there are two possible homes for almost every card, and the opening layout nearly always gives you somewhere to start. This page shows what the numbers say about a two-pack deal, how the game is played here, and how to make the most of the extra room.
A two-pack deal, measured
| What we measured | Result | Deals | How |
|---|---|---|---|
| Deals with no move among the nine face-up cards | 2.7% (95% range 2.4–3.0%) | 10,000 | Deal inspection |
| Single-pack Klondike, for comparison | 8.6% | 10,000 | Deal inspection |
| Aces starting face down (of 8) | 2.8 on average | 10,000 | Deal inspection |
| Computer player's win rate (Turn 1) | 81.5% (80.7–82.2%) | 10,000 | Rule-based player, no peeking, no Undo: a floor |
| Single-pack Klondike Turn 1, same kind of player | 42.3% | 10,000 | Same method |
| Moves in a won game (including stock turns) | about 268 | 8,145 wins | Same player |
| Passes through the stock in a won game | 2.7 on average | 8,145 wins | Same player |
No published study that we know of gives a figure for this game, so these are our own results with no outside check.
The two-pack rules on this site
The layout
- Two standard packs are shuffled together: 104 cards.
- Nine tableau columns are dealt, holding 1, 2, 3 and so on up to 9 cards. Only the bottom card of each is face up: nine face-up cards and 36 hidden ones.
- The other 59 cards form the stock.
- There are eight foundations: two for each suit.
Moves
- Tableau cards are built down in alternating colours, just as in Klondike, and whole builds can be moved together.
- Only a King, or a build headed by a King, may go into an empty column.
- The stock turns one card at a time onto the waste, and you can go through it as many times as you like. (The Draw 3 option on this page takes you to single-pack Solitaire Turn 3; Solitaire Double itself is always played one card at a time.)
- Each foundation is built up in suit from Ace to King. You win when all 104 cards are home.
Reading a two-pack deal
A blocked start is rare
With nine face-up cards drawn from two packs, only 2.7% of our deals offered no tableau move at the start, about a third of the single-pack rate. If you do get one of those rare deals, start with the stock rather than a new game: the computer player wins most deals regardless.
Expect about three hidden Aces
On average 2.8 of the eight Aces start face down. That sounds like a lot, but with two foundations per suit a buried Ace usually holds you back less than in single-pack Klondike: the other Ace of the suit can often start building in the meantime.
Look at the long columns
The ninth column hides eight cards, the eighth hides seven. Just as in Klondike, those hidden cards are where the game is decided, and they deserve your attention first.
Twins are your friends
Every card has a twin somewhere. When you are deciding where to put a red 8, check whether the other red 8s are already placed, and which black 9 is more useful to cover. Keeping track of both copies is the one genuinely new skill Solitaire Double asks for.
Strategy for the long game
Pace yourself
A won game took the computer player about 268 moves, including stock turns, roughly twice as many as single-pack Klondike. Settle in; this is a game for a long evening at the bach or a wet weekend.
Use the stock freely, but with a plan
Won games used 2.7 passes through the stock on average. Unlimited passes are part of why this game is so winnable, so there is no need to hoard stock cards. Just make each pass count by knowing what you are looking for.
Build both foundations of a suit
With two piles per suit, you can send a card home to whichever pile it fits. Building them evenly keeps more options open than racing one pile ahead.
Don't empty a column without a King
The Kings-only rule applies here too. With nine columns there is more room to work, but an empty column is still only useful if a King is ready to move into it.
Solitaire Double compared
If you enjoy two-pack games, FreeCell Two Decks gives you the same scale with every card face up. If you want the single-pack original, try Klondike Solitaire or the harder Klondike Turn 3. For another two-pack challenge with no second pass through the stock, try Forty Thieves.
Playing Solitaire Double on klondike.nz
It is free, with nothing to download, install or sign up for, and it runs in any modern browser on a computer, tablet or phone. With 104 cards on the table, the zoom control and fullscreen mode are especially handy, and you can tap a card and then its destination instead of dragging. Hint, unlimited Undo, Restart and Auto Play are all available, sound can be turned off, and the game tracks wins, time and moves.
Where these numbers come from
The klondike.nz team ran this study in September 2026 with the rules taken from this site's own code.
- Rules from our code. We read the two-pack Klondike code used by this page: 104 cards, nine columns of 1 to 9, a 59-card stock turned one card at a time with no limit on passes, Kings only into empty columns.
- A program copy of the game. We extended our single-pack Klondike program to nine columns, two packs and eight foundations.
- Numbered deals. 10,000 deals, each shuffled from a numbered seed, so anyone with the code can repeat the test exactly.
- Reading each deal. We counted the face-down Aces and checked whether any move was possible at the start.
- The player. A rule-following computer player that sees only the face-up cards, has no Undo and does not know the order of the stock. It is a floor: a patient person using Undo should do better.
- Comparison. We found no published figure for this game to compare against.
- Error bars. The 95% range of 80.7–82.2% is where this player's true win rate very likely lies.
- Limits. We did not run a solver that sees every card, so we cannot say how many two-pack deals are winnable with perfect play.
Under the bonnet
Written in Python 3.11 using only the standard library, in a module called doubleklondike.py built on the same player as our single-pack Klondike code. The shared runner spreads the deals across processor cores with multiprocessing, and ranges are Wilson score 95% intervals. We used an AI assistant, Claude by Anthropic, to help write and review the code and draft this page. None of the figures came from the AI: they come from running the code.
Questions players ask
Do two packs make the game tougher?
It is longer, but in our study it was much more winnable: 81.5% for our computer player, against 42.3% for single-pack Turn 1.
Can I play Solitaire Double with three-card turns?
Not on this site. The Draw 3 option switches to single-pack Solitaire Turn 3.
What are the eight piles at the top for?
Because there are two of every card. Each suit gets two piles, each built from Ace to King.
Is Solitaire Double a quick game?
We measured moves rather than minutes: about 268 moves in an average win for our computer player, roughly twice a single-pack game.
Where can I read about the study as a whole?
On our about page, and on the main Klondike page.
By Admin, klondike.nz. Study date: 19 September 2026.