A ball sort puzzle you can play right here
Ball sort is a tidy little logic puzzle. A rack of glass tubes holds colored balls, all mixed up. Lift the top ball of one tube, drop it into another, and keep going until every tube holds four balls of a single color. Each ball lands with a small click and a bounce, and a finished tube gets its cork. There is no timer and nothing to lose: just one calm move after another.
This version is free in your browser with no download. It has 300 levels in 12 chapters, three daily puzzles that are the same for everyone, a random mode, unlimited undo and hints. Every puzzle is solved by a computer before you see it, so it can always be finished, and the game tells you if your moves have led into a dead end.
How to play ball sort
- Lift a ball. Tap any tube with balls in it. Its top ball floats up out of the tube.
- Drop it. Tap a second tube. The ball flies across and drops in if that tube is empty or has the same color on top, and has room. Tap the first tube again to put the ball back.
- Sort every color. Each tube holds four balls. When a tube is full of one color it gets a cork and is done. Cork every color to solve the puzzle.
- Aim for par. Par is the fewest moves that solve the puzzle, found by our solver. Finish in par or fewer for three stars, within 30% more for two stars. Undo is free and does not count against you.
On a keyboard, Z undoes, R restarts and H shows a hint.
Ball sort tips and tricks
Is there a trick to ball sort puzzles? A few habits get you through almost every level:
- Protect the empty tube. An empty tube is the only completely free space on the board. Fill gaps in other tubes first, and empty it again as soon as you can.
- Build from the bottom. A tube whose bottom ball is already the color you want is a good home for that color. A tube with the wrong ball at the bottom must be emptied completely at some point.
- Look one ball down. Before you lift a ball, check what it uncovers. Freeing a color that has somewhere to go is worth more than a tidy-looking move.
- Don't split a color. Two tubes each topped with blue waste space. Move blue onto blue instead of starting it again in an empty tube.
- Count the gaps. Each color has exactly four balls, and every tube has room for four. Counting free spaces tells you how many balls you can park before you run out of room.
- Try, then undo. Play out an idea for a few moves and undo back if it stalls. The par only counts the moves in your final solution.
Can a ball sort puzzle be impossible?
Yes. A random shuffle can be impossible to solve even with perfect play. In 2022 a group of computer scientists studied ball sort and water sort together and showed that deciding whether such a puzzle can be solved is NP-complete: for big puzzles there is no known shortcut, and in the worst case you have to search.
That is why a computer solves every puzzle here before you play it. A solvable start can still turn into a dead end, for example when the last empty tube fills up with the wrong balls. After every move the game quietly checks whether a solution is still possible. If it is not, it says No way out from here and offers to undo exactly as many moves as you need. Stuck on a level in another app? Our ball sort and water sort solver finds the shortest solution for any position you enter.
Hidden colors: question mark balls
From chapter 3 on, some levels hide every ball below the top of each tube behind a question mark. A hidden ball shows its color only when it reaches the top. Uncover the tubes with the most question marks early, keep a spare space for surprises, and expect to change your plan when a new color appears. The par is still the best possible, worked out by a solver that can see through the question marks, so matching it takes some luck.
How the levels are made
Each level starts as a random shuffle of four balls per color plus two empty tubes, with no tube starting sorted or with three of a color stacked together. Then:
- A solver searches the possible moves, most promising first, and finds the shortest solution. Its length is the par. Shuffles with no solution are thrown away.
- To rate difficulty, a crowd of simulated players who move mostly at random try each puzzle. A level most of them finish is easy; one almost none finish has many dead ends.
- Levels climb from 2 colors in chapter 1 to 12 colors in chapter 12, with a harder level every fifth one and an easier breather after it.
| Chapters | Colors | What is new |
|---|---|---|
| 1–2 | 2–6 | The basics, then more colors |
| 3 | 3–6 | Hidden colors (question marks) |
| 4–8 | 5–9 | Fuller racks, alternating with hidden levels |
| 9–12 | 8–12 | The hardest puzzles, open and hidden |
Ball sort, water sort and other color sort games
Ball sort is also called color ball sort, sort balls or bubble sort puzzle. Its closest relative is the water sort puzzle, where you pour layers of colored water instead of moving balls: a whole layer moves at once, so you need fewer moves but have to think about where each pour lands. If you like puzzles that are always solvable, try the laser puzzle or our no-guess Minesweeper. For something with no thinking at all, there is the bubble popping game.
Frequently asked questions
How do you play ball sort?
Tap a tube to lift its top ball, then tap another tube to drop it there. A ball can only land on a ball of the same color or in an empty tube, and each tube holds four balls. The puzzle is solved when every tube holds four balls of one color.
Is there a trick to ball sort puzzles?
Keep at least one tube empty for as long as you can, because it is your only free space. Build each color from the bottom of a tube up, never stack a color on top of a different color unless you must, and before each move ask what the ball you lift will uncover.
Can a ball sort puzzle be impossible?
A random shuffle can be, and so can a position you reach after a few careless moves. Every level here is solved by a computer before you see it, so it can always be finished from the start, and the game warns you when your moves have left no way out and how many to undo.
How many levels are there?
There are 300 levels in 12 chapters, from 2 colors up to 12, plus three new daily puzzles every day and a random mode that builds a fresh puzzle whenever you like.
What do the question mark balls mean?
In hidden-color levels only the top ball of each tube shows its color. Balls marked with a question mark reveal themselves when they reach the top, so you plan with part of the picture.
What is the difference between ball sort and water sort?
They are the same puzzle with different pieces. In ball sort you move one ball at a time; in water sort a whole layer of one color pours at once. Ball sort takes more moves, but every single move is your choice.
Is there a daily ball sort puzzle?
Yes. Every day there are three new puzzles, Easy, Medium and Hard, the same for every player. Solve all three to keep your streak and share your stars.
Is this ball sort game free?
Yes. It runs in your browser for free, with no download and no account, on a computer, tablet or phone. Undo and hints are unlimited.