Spider Solitaire (1 suit): the version you can actually beat
Spider Solitaire has a reputation for being tough, and some versions deserve it. The one-suit game is different. Every card is a spade, so the only thing you have to think about is rank: a 7 goes on an 8, a 3 goes on a 4, and a full run from King down to Ace clears itself off the table. It is the gentlest way into Spider and a proper game in its own right, whether you have ten minutes on the bus into Auckland or a long wet evening in Invercargill.
We wanted a number behind that claim, not just a feeling, so we played 4,000 deals of one-suit Spider with a computer player that sees only the face-up cards and never takes a move back. It won 52.8% of them. A player who can undo, and who thinks harder than our bot, will do better still. In plain terms: if you lose a one-suit game, the next deal is better than a coin toss.
You can play it right here, free, with nothing to download and no sign-up. The rest of this page covers the rules, what our measurements found, and the habits that turn half your games into most of them.
The rules in two minutes
The layout
- Two full packs, 104 cards. In the one-suit game all 104 are spades, so there are eight identical runs to build.
- Ten tableau columns. The first four get six cards and the other six get five. Only the bottom card of each column starts face up.
- A stock of 50 cards in the corner. Each time you deal from it, one card lands face up on every column, which gives you five deals in total. There is no redeal once the stock is gone.
How cards move
- Any card can go on a card one rank higher: a 5 on a 6, a Jack on a Queen.
- A run in order (say 9-8-7) can be moved as a single block. With one suit, every ordered run qualifies.
- Any card, or any run, can go into an empty column.
- When a face-down card is uncovered, it turns face up.
- A complete run from King down to Ace is removed automatically. Clear all eight and you have won.
The game warns you if you try to deal from the stock while a column is empty, so fill every gap before you deal.
What 4,000 deals told us
| Measure (one suit) | Result | Games |
|---|---|---|
| Games won by our bot | 52.8% (95% range 51.2–54.3%) | 4,000 |
| Average runs cleared per game, out of 8 | 4.96 | 4,000 |
| Games with at least 4 runs cleared | 56.9% | 4,000 |
| Average moves in a won game, deals included | 117.5 | 2,111 wins |
| Games where a column was emptied before the first deal | 1.3% | 4,000 |
| Win rate in those games | 98% (51 of 52) | 52 |
Three things stand out.
Games are either won or lost fairly early. The share of games reaching four cleared runs (56.9%) is only a few points above the win rate (52.8%). Once the bot had cleared half the table, it nearly always finished the job. The hard part of one-suit Spider is the first half, when the table is crowded and most cards are face down.
An early empty column is almost a guaranteed win. Clearing a column before touching the stock is rare (about one game in 77), but when our bot managed it, it went on to win 51 of 52 games. The sample is small, so treat the exact figure with care, but the direction is clear: nothing in this game is worth more than an empty column.
A win takes about 120 moves. Our bot averaged 117.5 moves per win, counting the five deals. Most people take ten to twenty minutes over that, depending on how long they think between moves.
For comparison, the two-suit game dropped the same bot to 5.7% and the four-suit game to 0.2%. Adding suits does not make Spider a little harder. It changes the game entirely, and each of those pages explains why.
Playing Spider on this site
The game is completely free, with nothing to install and no account or email needed. It works in any modern browser on a computer, tablet or phone.
- Large, clear cards and a zoom control to make the board bigger, which helps a lot with ten columns on a phone screen.
- Hint when you are stuck, and unlimited Undo so you can test a line and back out of it.
- Restart to replay the same deal from the beginning.
- Auto Play to finish off a game that is already won.
- Drag and drop, or tap a card and then where it should go.
- Wins, time and moves tracked for the current game, fullscreen mode, a choice of table colours, and sound you can switch off.
There is no gambling, nothing to buy and no timer pushing you along.
Habits that win more games
1. Treat an empty column as the prize
Our data shows it plainly: empty a column early and you are very likely to win. Target the shortest columns first, and before each move ask whether it gets you closer to a clear column.
2. Turn over face-down cards before building tidy piles
A face-down card is information you do not have. When you have a choice, prefer the move that uncovers a card over the move that merely makes a run look neater.
3. Build on the higher card when there is a choice
If a 6 could go on either of two 7s, pick the column whose 7 is harder to shift. Keeping the easy column easy leaves you room later.
4. Clear the table before you deal
Each deal drops a new card on every column, burying whatever sat underneath. Make every useful move first. You have to fill empty columns before dealing anyway, so fill them with something you do not mind covering, not the base of a long run.
5. Use Undo as a scouting tool
Our bot never undoes a move, and it still wins more than half its games. You can. When a position has two sensible options, try one, look at what it uncovers, and back up if it goes nowhere. It is the quickest way to learn the game.
How we did the research, step by step
The free-solitaire.nz team ran this study in September 2026 to see how often one-suit Spider, as it is played on this page, is won by a player who can only see what is face up.
- Reading the rules from this site’s own game code. Two packs, 104 cards, all spades here. Ten columns (four of six cards, six of five) with the last card face up; a 50-card stock dealt one card to each column at a time, with no redeal. Any card may go on one rank higher, only same-suit runs move together, any card may fill an empty column, and a full King-to-Ace run is removed automatically. The game warns you if you try to deal while a column is empty; we assumed the usual rule that you cannot.
- Rebuilding the game as a program. We rewrote Spider in Python with those rules.
- Dealing the cards. Deals 100001 to 104000, 4,000 in all, each from a numbered seed. We tuned our player on a handful of other deals first, so these test deals played no part in setting it up.
- Choosing the player. A bot that sees only what you see and never undoes a move. Before each move it looks ahead through up to 250 positions, treating any card it would uncover as unknown, and picks the line that builds the most same-suit links, uncovers hidden cards and empties columns. Its result is a floor.
- Running it. The bot won 52.8% of the 4,000 deals and cleared 4.96 of the 8 suits on average.
- Checking against published research. We found no published figure for one-suit Spider. For comparison, Blake & Gent, Journal of Artificial Intelligence Research, 2026 put four-suit Spider at 98.487% when every card is known.
- Working out the margin of error. A “95% range” is the band the true figure falls inside 95 times out of 100 if you ran the same test again on fresh deals. The bot’s 52.8% came with a range of 51.2–54.3%.
- What the numbers cannot tell you. A patient player with Undo will win more than our bot, and we did not run a solver that sees every card, so we cannot say how many one-suit deals are winnable in theory.
Every deal is seeded, so the whole test can be repeated exactly.
The technical side
Spider runs in Python 3.11 with the standard library only, in spider.py; one setting chooses 1, 2 or 4 suits. A shared runner.py plays 19 deals at once on separate processor cores with Python's multiprocessing. Each deal is shuffled from a numbered seed, and the Spider runs start at seed 100001.
- The bot does a short best-first look-ahead each turn: it explores up to 250 positions using only the cards a player could see, treating every newly uncovered card as unknown. It keeps a set of positions already explored so it never retraces its steps. It then plays the line with the best score, which rewards same-suit links and empty columns and penalises face-down cards.
- Scale. The 4,000 one-suit deals took about 21 minutes.
- The 95% range is a Wilson score interval.
One safeguard matters here. We chose the bot's scoring weights after trying it on seeds 1 to 30, so the reported runs use seeds from 100001 upwards, deals that played no part in tuning. An AI assistant (Claude, by Anthropic) helped us write and review the code and draft this page. The AI did not produce any figure; every number comes from running the code, and we checked the results against published research.
By Admin, free-solitaire.nz. Study date: 18 September 2026.
Frequently asked questions
What percentage of one-suit Spider games can be won?
Our bot, which cannot see hidden cards and never undoes, won 52.8% of 4,000 deals. Players with more patience win more: real-player figures published by solitairex.io put one-suit Spider at 70–84%. Very few deals are truly impossible.
Is one-suit Spider easier than Klondike?
For most people, yes. With one suit there is no colour or suit to match, so it comes down to rank order and good use of space. Klondike leans more on the luck of the stock, especially Turn 3.
Can I deal when a column is empty?
The game warns you if you try. Fill every empty column first, ideally with a card you are happy to have covered.
How long does a game take?
A won game takes our bot about 118 moves. For a person, that usually means ten to twenty minutes.
When should I move up to two suits?
Once you are winning more one-suit games than you lose, try Spider 2 Suits. Expect your results to drop a long way at first. That is normal, and the page explains why.
Do I need an account to play?
No. Nothing to download, no sign-up, no email. Open the page and the cards are dealt.
What else can I play?
If you like the look-ahead side of Spider, try FreeCell, where every card is visible from the start, or Yukon, where you can move whole piles. The full list is on the games page.