Solitaire Double: when the deck is generous, how much is left for strategy?
Solitaire Double is Klondike played with two full decks: 104 cards, nine tableau columns and eight foundations. On spidersolitaireonline.us we ask of every game how far a thought-out strategy lifts you above simple, move-by-move play. Solitaire Double gives an unusual answer: simple play already goes a long way.
A bot that sees only face-up cards, follows a fixed priority list and never undoes won 81.5% of 10,000 two-deck deals (95% range 80.7% to 82.2%). The same kind of bot wins 42.3% of one-deck Klondike. We did not run a planning search on Solitaire Double, so we cannot say how many deals are winnable in principle. What we can say is that planning has less ground to make up here than in almost any other game on the site, and that its job shifts from rescuing lost games to finishing long ones cleanly.
Solitaire Double at a glance
| What we measured | Result | n | 95% range |
|---|---|---|---|
| No-plan bot win rate, two decks, one-card draw | 81.5% | 10,000 deals | 80.7–82.2% |
| Same bot, one-deck Klondike, for comparison | 42.3% | 10,000 deals | 41.3–43.3% |
| Moves in the bot's wins (stock draws included) | 268.1 | 8,145 wins | 267.8–268.4 |
| Stock passes in the bot's wins | 2.7 | 8,145 wins | 2.67–2.70 |
| Deals with no move among the 9 face-up cards | 2.7% | 10,000 deals | 2.4–3.0% |
| Aces starting face down (of 8) | 2.8 | 10,000 deals | 2.76–2.81 |
| Planning search (winnable in principle) | not run | – | – |
The 81.5% is a floor for a person, not an average: the bot never plans and never takes a move back. Blake and Gent's published study does not cover two-deck Klondike, so there is no outside figure to compare with.
The two-deck rules here
- Cards: two standard decks shuffled together, 104 cards.
- Tableau: nine columns of one to nine cards, 45 in all, with the bottom card of each face up.
- Stock: the other 59 cards, turned one at a time. The Draw 3 option takes you to single-deck Solitaire Turn 3.
- Redeals: unlimited.
- Foundations: eight, two per suit, each built from Ace to King.
- Building: down in alternating colors; ordered runs move together.
- Empty columns: Kings, or runs headed by a King, only.
Where strategy still pays in a two-deck game
Why simple play does so well
Every card has two twins. A red 7 can go on any of four black 8s instead of two, and each suit has two foundations. Dead ends are rarer: only 2.7% of deals start with no move among the face-up cards, against 8.6% in one-deck Klondike. A greedy move is less likely to trap you when a second copy of the card you need is somewhere on the table.
Choose between twins
This is where thinking ahead earns its place. When two 8s could take your 7, pick the one whose column hides more face-down cards, because moving onto it leaves you closer to digging it out.
Dig the right-hand columns early
The ninth column holds nine cards, eight of them hidden, and the last three columns hide 21 of the 36 face-down cards between them. A plan that works on them early keeps the game moving.
Keep paired foundations level
Racing one hearts pile far ahead of the other sends up cards you may still need in the tableau. Building the twin piles evenly keeps your landing spots open.
Be patient with a long game
The bot's wins took about 268 moves on average and 2.7 stock passes, roughly twice the moves of a one-deck win. A careful player spends those moves better, but should not expect a shorter game.
Use Undo for the one in five
The bot lost about 18.5% of deals. Some of those are surely lost for anyone; others were given away by a move it could not take back. Unlimited Undo lets you test a choice between twins and reverse it if it goes wrong.
Made for a wide table
With nine columns and 104 cards, the zoom control and fullscreen mode help. Solitaire Double is free in any modern browser on computer, tablet or phone, with no sign-up. Hint, unlimited Undo, Restart, Auto Play, drag or two-tap moves, and a live count of wins, time and moves are all included; sound and table color are in the settings.
How we tested it
The spidersolitaireonline.us team ran this test on September 19, 2026, on the rules in this site's own game code.
- Read the game code: 104 cards, nine columns of one to nine, a 59-card stock at one-card draw, unlimited redeals, alternating-color builds and Kings-only spaces.
- Extended our Python Klondike program to nine columns and two foundations per suit.
- Dealt 10,000 numbered hands from seeds 1 to 10,000, so the test repeats exactly.
- Used one player: a bot that sees only face-up cards, works through a priority list and never undoes.
- Played every deal to the end and recorded wins, moves and stock passes, and inspected every opening layout.
- Looked for published figures. Blake and Gent (2026) do not include two-deck Klondike.
- Named the limits. We have a floor but no ceiling: no planning search was run for this game, so the share of winnable deals is unknown.
The code uses only the Python standard library; all 10,000 deals ran in about five seconds across 19 processes. Ranges are Wilson score intervals for percentages and normal intervals for averages. Claude, an AI assistant made by Anthropic, helped us build and check the program and draft this page; every figure comes from running the code.
Solitaire Double questions
Is it easier than ordinary Klondike?
For simple play, much easier: 81.5% won against 42.3% for one deck with the same bot.
Does strategy matter if simple play wins so often?
Less than in most games, but yes: choosing between twin cards and pacing the paired foundations is where careful players pull ahead.
Can I play it with a three-card draw?
Not in the two-deck version here. Draw 3 takes you to single-deck Solitaire Turn 3.
What should I try next?
For a two-deck game where planning matters more, try FreeCell Two Decks. The one-deck game is on our Klondike page, and everything else is on the games page.
By Admin, spidersolitaireonline.us (Solitairen OOD). Research run September 2026.