Free Solitaire Solver: Check If Your Klondike Game Is Winnable
Some Klondike deals cannot be won from the moment the cards are dealt. Without a solver, you can spend ten minutes on a doomed game without knowing. Our solver runs in your browser, checks every position you reach, and tells you in real time whether the game still has a winning path. It also lets you start with a deal that has a verified solution and rewind to the last solvable state when you slip. And when you want help, the Hint button shows the next move of the solver's winning line, one move at a time.
Play Solitaire with Built-in SolverTable of Contents
- What Is a Solitaire Solver?
- How to Use the Solver
- Solver-Powered Features
- Hints That Follow the Solver
- How the Solver Works
- Solvability — The Real Numbers
- Built-in vs External Solvers
- FAQ
What Is a Solitaire Solver?
A solitaire solver is a program that searches the tree of legal Klondike moves. Starting from your current position, it tries one move, then another, and another — looking for a sequence that ends with all 52 cards on the foundations. Think of it as a chess engine for solitaire.
Most solvers are standalone tools. You enter your card layout by hand, wait, and read the answer. Ours is built into the game. It reads your position automatically, runs in the background, and updates the toolbar icon as you play. No setup, no copying card values, no breaking your flow.
- No manual entry. The solver reads the board for you.
- Live feedback. Check at any point during play.
- Deal Winnable. Start with a hand that has a known solution.
- Undo to Last Winnable. Rewind to the last solvable state when you slip.
- Hints. Press Hint to see the next move of a winning line.
- Free. No account, no usage cap.
- Private. Runs in your browser. No data leaves your device.
How to Use the Solver
The solver lives in the game toolbar. Each icon means something different.
What each icon means
- Green checkmark — a winning path exists from this position. You may not see it yet, but it's there.
- Red X — no winning path exists. Click to open the recovery panel.
- Gold spinner — the solver is analyzing. Most checks finish in a few seconds.
- Gray question mark — not yet checked, or the search timed out. Click to run it.
Step-by-step
- Start a new game. The solver checks the deal in the background.
- Play normally. Make your moves the way you would in any Klondike game.
- Click the icon. A click triggers a fresh check at any point.
- Green? Keep going — a solution exists.
- Red? Open recovery. The fastest path is Undo to Last Winnable.
- Stuck? Press Hint for the next move of a winning line.
Solver-Powered Features
Deal Winnable
Choose Deal Winnable in the new-game menu. The solver picks a seed with a verified solution before any cards are dealt. You skip the unwinnable deals entirely. Available in Draw 1 and Draw 3.
When to use Deal Winnable
- Learning. Practice strategy without losing time on impossible deals.
- Short sessions. A coffee break shouldn't end on a deal that was already lost.
- Draw 3. Fewer Draw 3 deals have a solution, and players win far fewer of them. Starting solvable removes a major variable.
- Building a streak. Solvable deals reward improvement directly.
Undo to Last Winnable
When the solver finds that no winning path remains, the icon turns red. Click it, and the recovery panel opens. Hint opens the same panel when its own search proves the loss. The most useful option is Undo to Last Winnable — it rewinds to the last position with a solution. You don't lose your progress; you just back up a few moves and try a different line.
- Undo to Last Winnable. Rewinds to the last solvable position and shows how many moves that is. Best option in most cases.
- Undo Last Move. Takes back one move.
- Play Again. Starts the same deal again from the beginning.
- Deal Winnable. Starts a new deal with a verified solution.
- Dismiss. Closes the panel so you can play on.
When a hint opens the panel, it also offers Show a Move Anyway: a legal move, for when you want to keep playing. On a deal that could never be won, there is nothing to undo to, so the panel says "This deal is not winnable." Click the red icon on a new deal and the game skips the panel and deals a winnable game.
Background analysis on every new deal
The solver checks each new deal automatically. Within seconds you see whether the game has a solution — before your first move. Useful in Draw 3 especially, where practical win rates are low.
On-demand position check
Click the icon mid-game to check your current position. The solver looks at your exact state, not the original deal. It accounts for every move you've made.
Hints That Follow the Solver
The solver also drives the Hint button. Press it, or the H key, and the game shows one move. A gold ring marks the card to move and a blue ring marks where it goes. A faint copy and an arrow show where the card lands, and one sentence says what to do and why.
How does the hint choose a move?
- A winning line first. When the solver has found a win from your exact position, the hint is the next move of that line. The sentence names what the move does, or says "It is the next step of a winning line." Play it, and the next hint comes at once.
- About a second to think. Each press gives the solver about one second. If it cannot decide in that time, you get a useful move from the board at once, and your next press asks the solver again.
- No circles. The old hint could move a card back and forth for ever. The new one does not: in our tests, following it never went round in a loop.
- Another move. Want a choice? Press Another move in the caption. On a winning line, it offers only moves after which the solver can still win.
The solver sees every card, the face-down ones included, so a hinted move can look odd and still be right. A hint costs no points. When its search proves the game lost, the hint offers no move: it opens the recovery panel shown above. With the Solver setting off, the hint still picks its moves with the solver, but it never talks about winning and offers no Undo to Last Winnable.
FreeCell and Spider hints have solvers of their own. In FreeCell, where every card is face-up, the hint follows a solved line in almost every deal. Spider hints look ahead through the face-down cards and follow a win when the solver finds one, but they never tell you a game is lost: in Spider, a search that finds no win proves nothing.
How much better is the new hint? Our blog post tests the old hint and the new one on the same deals.
How the Solver Works
For readers who want the details under the hood.
Algorithm
The solver runs a depth-first search and keeps a table of every position it has visited. From your current position it tries the most promising moves first — those that turn over a face-down card or build a foundation — and backs up when a line leads nowhere. It sees every card, the face-down ones and the order of the stock included. A "yes" comes with a complete winning line. A "no" is a proof: the search visited every position the game can reach. When time runs out first, the answer is "not sure", never "no".
Optimizations
Klondike has an astronomical state space, so brute force isn't viable. The solver uses several tricks, none of which can turn a winnable position into a "no":
- Safe foundation moves. Aces and 2s go up at once, and so does any card that no other card can still need. The solver doesn't branch on those moves.
- State deduplication. Each position gets a 64-bit fingerprint that ignores the order of the seven columns. A position reached twice is searched once.
- One step per stock card. The game lets you turn the stock over as often as you like, so the solver plays any reachable stock card in one step, then writes the draws back into the line.
- Fresh starts. If the search spends too long on a bad first guess, it pauses for a few short searches in a shuffled move order, then resumes where it stopped.
Performance limits
- A new deal. Up to 20 million positions or 30 seconds.
- A check you ask for. Up to 30 million positions or 60 seconds.
- A hint. About one second, in a worker of its own, so a hint never waits behind a long check.
- Background thread. Runs in a Web Worker. The game UI never freezes.
- Compact state. Cards are stored as integers (0–51), not objects. Memory stays small.
Privacy
The solver runs entirely in your browser. No API calls, no telemetry, no server. Your game state never leaves the device. Once the page has loaded, the page works offline.
Solvability — The Real Numbers
Klondike's winnability has been a research question since the 1990s, and the literature is messier than most casual sources suggest. Here are the numbers that hold up.
Solver results: every card known
The most precise result comes from a solver study by Charlie Blake and Ian Gent. Their solver sees every card, including the face-down ones, and may cycle the stock without limit. It can win about 90% of Draw 1 deals and about 82% of Draw 3 deals (Blake & Gent, 2026). The rest have no solution at all. These figures are a ceiling for perfect play with full information, not a player win rate.
What players actually win
Players cannot see the face-down cards, so they win far fewer games than the solver. In August 2026, TrySolitaire players won 35.3% of the Draw 1 games they started and 15.5% of the Draw 3 games, counting games they left unfinished as not won (August 2026 player report).
The Draw 3 gap has two parts. Fewer Draw 3 deals have a solution at all, and the stock-pile constraint makes it harder to reach the moves you need in the deals that do.
Why the solver matters
Some deals have no solution in either mode. Without a solver you can't tell. With Deal Winnable on, every game starts solvable — your skill becomes the only variable. With Undo to Last Winnable, slipping into an unsolvable position is no longer terminal.
Keep the two kinds of number apart
Many pages mix solver figures and player figures. A solver figure tells you how many deals have a solution when every card is known. A player figure tells you how many started games people actually won. When you compare sources, check which of the two a number measures.
Built-in vs External Solvers
Most Klondike solvers online are standalone web pages or downloadable tools. Here's how the built-in solver compares.
| Feature | TrySolitaire (built-in) | External solver tools |
|---|---|---|
| Input method | Reads board automatically | Manual card entry |
| Real-time check | Yes, during play | No, separate tool |
| Deal Winnable | Yes | No |
| Undo to Last Winnable | Yes | No |
| Next move on request | Yes, one move at a time (Hint) | Usually the whole solution at once |
| Privacy | Client-side only | Often server-side |
| Cost | Free, no limits | Often capped or paid |
| Draw 3 support | Yes | Varies |
| Works offline | Yes | Rarely |
FAQ
What is a solitaire solver?
A solitaire solver searches the tree of legal Klondike moves to find a sequence that wins from your current position. TrySolitaire's solver runs in your browser and tells you whether such a sequence exists. The status icon shows only that answer. Press Hint and the game shows the winning line one move at a time.
Is the solver free?
Yes. No account, no premium tier, no usage limits. Deal Winnable, Undo to Last Winnable and hints are also free, and a hint costs no points. The solver works offline once the page has loaded.
Does the solver tell me the moves?
Only when you ask. The status icon tells you whether a winning path exists, not what it is, so the puzzle stays yours. Press Hint and the game shows the next move of the solver's winning line, with an arrow and one sentence that says why. Press it again after each move for the next step.
Does the solver work on mobile?
Yes. iPhone, iPad, Android phones, Android tablets, and desktop browsers all run the same Web Worker. A slower device searches fewer positions in the same time, so a hard position can take it longer to decide.
Does it support Draw 3?
Yes. Both Draw 1 and Draw 3 are fully supported. Draw 3 is where the solver earns its keep — fewer Draw 3 deals can be won, and players win far fewer of them.
How accurate is it?
When the icon is green, the solver has found a complete winning path. When it's red, the solver has searched every position the game can reach from yours and proved that no path exists. A very tangled position can run out of time first: 30 seconds for the check of a new deal, 60 seconds for a check you ask for. The icon then shows a gray question mark.
Is my game data sent to a server?
No. The solver runs in a Web Worker — a background thread inside your browser. Your moves, board state, and analysis results never leave your device.
Can I use the solver to cheat?
The status icon tells you whether you can win, not how. Knowing a game is solvable doesn't make finding the solution any easier. The Hint button shows a move whenever you ask, and a hint costs no points, so how much help you take is up to you. Use the icon to skip doomed deals and keep the moves for yourself, or take a hint when you want one.
What makes this solver different?
External solvers are standalone tools that need manual card entry. This one is built into the game, reads your board automatically, runs in the background, offers Deal Winnable and Undo to Last Winnable, drives the Hint button, and stays client-side. We know of no external tool that offers all of these together.
Try the Solver Now
Play Klondike with the built-in solver — free, no sign-up.
Play Solitaire with Solver✓ Built-in solver | ✓ Deal Winnable | ✓ Undo to Last Winnable | ✓ Solver hints | ✓ Free
Related
- Klondike Solitaire — rules, strategy, and the Wes Cherry story
- Is My Solitaire Game Winnable? — the difference between theoretical and practical solvability
- Klondike Strategy Guide — six concrete strategies that move the needle
- How to Win at Solitaire — patterns that work across the family
- Spider Solitaire Win Rates — how solvability changes with 1, 2, and 4 suits
References & Sources
- Blake, C., & Gent, I. P. (2026). "The Winnability of Klondike Solitaire and Many Other Patience Games." Journal of Artificial Intelligence Research (preprint arXiv:1906.12314, first posted 2019). Solver study with every card known and unlimited redeals: about 90% of Draw 1 deals and about 82% of Draw 3 deals can be won.
- TrySolitaire. "TrySolitaire August 2026: What 147,673 Games Tell Us." Published 1 September 2026. Player win rates: wins divided by all games started, with unfinished games counted as not won.
- Bjarnason, R., Fern, A., & Tadepalli, P. (2009). "Lower Bounding Klondike Solitaire with Monte-Carlo Planning." Proceedings of the International Conference on Automated Planning and Scheduling (ICAPS) 19. An earlier estimate of Klondike winnability when every card is known, and a foundation for modern Klondike solver design.
- The depth-first search with a table of visited positions described on this page is a standard technique in game-tree search; see Russell, S. & Norvig, P. Artificial Intelligence: A Modern Approach (4th ed., 2020), Chapter 3.