Diplomat Solitaire: the one game where we can only tell you the floor

Diplomat is a two-deck game with a calm, open look. Eight short columns of four cards sit face up in front of you, eight foundations wait to be filled, and a 72-card stock feeds you one card at a time. There is only one pass through that stock, so every card you let go by is gone for good.

This site's research is about ceilings: what share of deals perfect play could win. Diplomat is the exception. We did not build a solver for it, and no published study covers it. What we did measure is how a sensible computer player fares when it knows no more than you do about the stock. It won 47.9% of 2,000 deals, and on average it got 76 of the 104 cards home.

That is a floor, not a ceiling. With better play, and with Undo, more deals can be won. How many more is something nobody has measured. You can play Diplomat here for free, in any browser.

Diplomat: the floor in numbers

The most complete published survey of solitaire winnability, Blake & Gent (2026), covers dozens of games but not Diplomat. As far as we know, our figures are the only ones published for this game.

Why this floor is a good one

For most games on this site, our no-peeking computer players are simple, and their results sit far below the ceiling. Diplomat's player is different in one useful way: its figure is close to a coin toss already. Even without knowing what the next stock card is, it wins nearly half its games, and across all 2,000 games it averaged 76 of the 104 cards home.

So Diplomat is forgiving. Two decks mean two of every card, which usually gives you a second chance when the first copy is stuck. Most of the challenge comes from the single pass through the stock, not from the layout.

Diplomat rules on this site

• Two standard decks, 104 cards.
• The table starts with eight face-up columns, four cards in each.
• The other 72 cards form the stock. Turn them one at a time onto the waste pile.
• There is no redeal: when the stock is empty, it stays empty.
• Columns build down regardless of suit, and only one card moves at a time.
• Any card may go into an empty column.
• Eight foundations build up by suit, Ace to King.

Getting past the floor

Look before you turn

Before each stock card, make every useful move you can on the table. Once a card is on the waste pile under others, it is hard to reach.

Play from the waste before it buries itself

Because there is no redeal, cards buried in the waste may never come back. Play from the waste whenever it does not cost you something important on the table.

Empty columns are worth a lot

Any card can go into an empty column, and only one card moves at a time, so an empty column is the easiest way to rearrange a stack.

Remember there are two of everything

If one 5 of hearts is buried, the other may turn up in the stock. Don't wreck a good column to dig for a card that has a twin still to come.

Don't bury low cards under high ones

Since you can only move one card at a time, a 3 stuck under a Queen, Jack and 10 takes three separate moves and three landing spots to free.

Where Diplomat might sit on the ceiling ladder

Because we have only a floor for Diplomat, it is worth comparing floors rather than ceilings. Our no-peeking players, all built on the same idea of seeing only what you see and never undoing, produced these win rates:

• Diplomat: 47.9% of 2,000 deals.
• Klondike Turn 1: 42.3% of 10,000 deals.
• Pyramid: 25.2% of 4,000 deals (a greedy player).
• Golf: 22.4% of 10,000 deals (a greedy player).

Diplomat's floor is the highest of these. For Klondike, the ceiling turned out to be at least 76.6% with perfect play; for Golf, 92.7%. Nobody has measured Diplomat's ceiling, but a high floor is usually a sign of a forgiving game, and two copies of every card give you more ways out than a single deck does.

Inside the test, one step at a time

The solitaire-online.us team ran this study in September 2026. For Diplomat, the aim was to measure a solid floor under this site's rules.

1. Reading the rules from our game code. Two decks, eight columns of four face up, a 72-card stock with no redeal, building down regardless of suit, single-card moves and any card into an empty column all come from this page's game files.
2. Rebuilding the game. We wrote Diplomat as a program with those rules.
3. Dealing the cards. Seeds 1 to 2,000, each producing the same two-deck shuffle every time.
4. Choosing the player. A look-ahead player that searches 300 positions each turn over the table and waste pile. Like you, it has no idea which card the stock will turn up next. We did not build a solver for Diplomat.
5. Running it. 2,000 deals, each played until won or until the stock ran out with no useful moves left.
6. Checking against published research. None exists for Diplomat, so there is nothing to compare with. We say so rather than borrow a figure from a different game.
7. Working out the margin of error. In 19 of 20 repeats, the true win rate for this player would fall in our 95% range of 45.7–50.0%.
8. What the numbers cannot tell you. Our 47.9% is a floor for one reasonable strategy. It does not tell you how many Diplomat deals can be won with perfect play.

The code behind the ceiling

The study is Python 3.11 with only the standard library. Diplomat has its own module, diplomat.py, and the shared runner.py divides deals among 19 worker processes on a 20-core machine. Each deal is rebuilt from its seed.

On each turn, the player runs a search of up to 300 positions over table and waste moves. It scores a position by adding points for every card on the foundations, links in order and empty columns, and taking points off for cards sitting on a lower card and for each card in the waste. It plays toward the best position it found, and turns the next stock card only when nothing improves the score. The 2,000-deal run took about 14 minutes. The range uses the Wilson score interval.

Claude, the AI assistant made by Anthropic, helped us write and check the code and prepare a first draft of this page. The AI did not produce any of the figures; they are the output of the program.

Because each shuffle comes from a numbered seed, anyone with the same code gets exactly the same deals and the same verdicts.

By Admin, solitaire-online.us. Study date: September 18, 2026.

Ceiling questions from players

What share of Diplomat deals can be won?

Our computer player, without knowing the stock order, won 47.9% of 2,000 deals. With better play the figure is higher, but no one has measured the ceiling.

Why is there no redeal?

That is how Diplomat is played here: the 72-card stock goes through once. It is the main source of difficulty.

How many moves does a Diplomat win need?

Our player's wins took about 351 moves, including stock turns. Two decks make it a longer game than Klondike.

Are group moves allowed in Diplomat?

No, only one at a time. That makes empty columns especially useful.

What's similar to Diplomat?

For another open, planning-heavy game, try FreeCell. For a quick one, try Golf. Everything is on the games page.