FreeCell with one deck: the 52-card original next to its 104-card big brother
This site is named after the two-deck version of FreeCell, and this page plays the original: one deck, eight columns, four free cells. Putting the two side by side is the quickest way to see what a second deck really does to the game. Short answer: it does not make deals unfair, it makes them long.
With 52 cards, our search program settled almost everything. It solved 99.7% of 10,000 one-deck deals (95% range 99.5%–99.8%) after a second, longer search on the hard ones, and proved none of them impossible. With 104 cards on this site's two-deck table, a comparable search solved 88.0% of 400 deals (84.4%–90.8%), also proved none impossible, and simply ran out of budget on the other 12.0%. Its winning lines averaged 148.0 moves, against 62.2 for one deck.
At a glance: one deck vs two decks
| Measure | FreeCell, 1 deck (this page) | FreeCell Two Decks |
|---|---|---|
| Cards / columns / free cells | 52 / 8 / 4 | 104 / 10 / 8 |
| Deals solved by our search | 99.7% (99.5%–99.8%), 10,000 deals | 88.0% (84.4%–90.8%), 400 deals |
| Proven impossible | 0.0% (0.0%–0.04%) | 0.0% (0.0%–1.0%) |
| Left undecided when the budget ran out | 0.3% (0.2%–0.5%) | 12.0% (9.2%–15.6%) |
| Length of first winning line found | 62.2 moves (61.9–62.4), 9,913 solved | 148.0 moves (145.9–150.1), 352 solved |
| An Ace playable on move one | 49.0% (48.0%–49.9%) | 55.0% (50.1%–59.8%) |
The search budgets were not the same: up to 200,000 positions per one-deck deal, then 1,000,000 for the leftovers, against 150,000 per two-deck deal. So the gap in "solved" is partly a gap in effort. What stays true is that neither table produced a single proven-impossible deal.
What four cells are worth with one deck
The two-deck game hands you eight cells. The one-deck game gives you four, and each one matters. We re-ran 3,000 one-deck deals at every smaller cell count; the published column is from Blake and Gent (2026).
| Free cells | Solved | 95% range | Proven impossible | Published |
|---|---|---|---|---|
| 4 (as played here) | 99.7% | 99.5%–99.8% | 0.0% | 99.9989% |
| 3 | 96.0% | 95.3%–96.7% | 1.0% | 99.36% |
| 2 | 74.0% | 72.4%–75.5% | 20.2% | 79.54% |
| 1 | 17.4% | 16.1%–18.8% | 79.6% | 19.35% |
| 0 | 0.2% | 0.1%–0.4% | 99.7% | 0.21% |
The curve bends hardest between two and one cell. We did not run a cell-count curve for the two-deck game, so we cannot say where its bend is; eight cells for twice the cards is the same ratio, but a longer game gives more chances to clog them.
The one-deck rules on this site
- Deal: 52 cards face up in eight columns, four of seven and four of six.
- Free cells: four, one card each.
- Foundations: four, one per suit, Ace up to King.
- Building: down in alternating colors.
- Empty columns: any card.
- Group moves: a run moves at once if it fits in empty cells plus empty columns, plus one.
Habits that carry between the two tables
One copy of each card means no second chance
On the two-deck table a red 7 has two black 8s to aim for. Here it has exactly one. If that 8 is buried, there is no twin to fall back on, so find where each key card sits before committing.
Treat the fourth cell as a reserve
Dropping from four cells to three cost only a few points in our tests; dropping to two cost about a quarter of all deals. Keep at least two open while you work.
A one-deck win is a sprint
About 62 moves against about 148 on two decks. Mistakes show up fast here, so a short plan executed cleanly is enough.
Use this table to train for the big one
Everything you learn about empty columns and cell discipline scales up to FreeCell Two Decks, where the same skills have to hold for more than twice as long.
Playing FreeCell on freecell-two-decks.com
Free in any modern browser on computer, tablet or phone, with no download and no account. Hint, unlimited Undo, Restart and Auto Play are built in, with large cards and zoom, drag or tap to move, a count of wins, time and moves, and settings for sound, fullscreen and table color.
How we compared the two
The freecell-two-decks.com team ran these tests in September 2026 on the rules in this site's own game code.
- Rules read from the code for both games: layouts, cell counts, alternating colors, any card in a gap.
- Numbered deals: one deck used seeds 1–10,000 (1–3,000 per reduced-cell version); two decks used seeds 101–500, because seeds 1–8 were used to tune its search.
- A best-first solver for both. Nothing is hidden, so it sees what you see.
- Different budgets, stated above, so the solved shares are not a like-for-like difficulty score.
- Published check: Blake and Gent (Journal of Artificial Intelligence Research, 2026) cover one-deck FreeCell; they do not cover the two-deck game.
- 95% Wilson score intervals on every percentage.
The code is Python 3.11, standard library only. Claude, an AI assistant by Anthropic, helped write and review the code and draft this page; every figure comes from running the code.
FreeCell questions
Is one-deck FreeCell easier than two decks?
Shorter and easier for a search program to finish: 99.7% solved against 88.0%. Neither produced a proven-impossible deal in our samples.
Can every deal be won?
Nearly. None of our 10,000 was proven impossible; the published estimate is 99.9989% winnable.
Where next?
Step up to FreeCell Two Decks or read its rules and figures. For same-suit building try Eight Off. Every game is on the games page.
By Admin, freecell-two-decks.com (Forty Media). Research run September 2026.