A water sort puzzle you can play right here
Water sort is a calm little logic puzzle. A rack of glass tubes holds layers of colored water, all mixed up. Pour from one tube into another until every tube holds a single color, then watch it get its cork. There is no timer and nothing chasing you: just the glug of the water, the next pour and the small click when a color comes together.
This version runs 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 checked by a solver before you see it, so it can always be finished, and the game tells you if your pours have led into a dead end.
How to play water sort
- Pick up a tube. Tap any tube that has water in it. It lifts a little.
- Pour it. Tap a second tube. The top color pours across if the second tube is empty or has the same color on top. If two or three layers of that color sit together on top, they all pour, as far as there is room.
- Sort every color. Each tube holds four layers. When a tube is full of one color it gets a cork and is done. Solve the puzzle by corking every color.
- Aim for par. Par is the fewest pours that solve the puzzle, worked out 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.
Water sort tips and tricks
Is there a trick to water sort puzzles? Not one single trick, but a handful of habits solve almost every level:
- Guard your empty tube. An empty tube is your most valuable move. Use the tubes that already have room before you pour into an empty one, and try to get it back empty as soon as you can.
- Never start a color twice. If one tube already has blue on top with room above it, pour blue there, not into an empty tube. Two half-tubes of the same color waste space you will need later.
- Finish what is nearly finished. A tube with three layers of one color needs one more pour. Closing it frees your attention and often frees a layer somewhere else.
- Count what is missing. Every color has exactly four layers. When you know where the four greens are, you can plan the order in which they come free.
- Dig toward the buried colors. A color whose layers are all at the bottoms of tubes is the hardest to sort. Clear the layers above them early.
- Undo is a tool, not a failure. Try a line of pours, see where it leads, then undo back. The par counts only the pours in your final solution.
Can a water sort puzzle be impossible?
Yes. Shuffle the colors at random and some puzzles cannot be solved at all, even with perfect play. In 2022 a group of computer scientists showed that deciding whether a water sort puzzle can be solved is NP-complete, which is a formal way of saying there is no known shortcut for big puzzles: in the worst case you have to search.
That is why every puzzle here is solved by a computer before you play it. Even so, a solvable start can still turn into a dead end: one careless pour into the last empty tube can leave nowhere useful to go. After every pour 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 to get back on track. Stuck on a level in another app? Enter it in our water sort solver and it will show you the shortest way through.
Hidden colors: the question mark levels
From chapter 3 on, some levels hide the layers under the top of each tube. You see a question mark instead of a color until that layer reaches the top. It turns water sort into a game of partial information: free the tubes with the most question marks early, keep a spare tube for surprises, and expect to change plans when a color appears. The par for these levels is still the best possible, worked out by a solver that can see through the question marks, so beating it means some luck as well as skill.
How the levels are made
Each level starts as a random shuffle of four layers per color plus two empty tubes, with no tube starting already sorted or with three of a color stacked together. Then:
- A solver searches every sequence of pours, smartest first, and finds the shortest solution. That length is the par. If no solution exists, the shuffle is thrown away.
- To rate difficulty, a crowd of simulated players who pour at random try each puzzle. A level that most of them finish is easy; one that almost none finish has many dead ends.
- Levels are ordered by that rating, with a harder level every fifth one and an easier breather after it, from 2 colors in chapter 1 up to 12 colors in chapter 12.
| Chapters | Colors | What is new |
|---|---|---|
| 1–2 | 2–7 | The basics, then more colors |
| 3 | 3–7 | Hidden colors (question marks) |
| 4–8 | 6–10 | Fuller racks, alternating with hidden levels |
| 9–12 | 9–12 | The hardest puzzles, open and hidden |
Ball sort, color sort and other sorting games
Water sort has close relatives. Ball sort is the same puzzle with stacks of colored balls instead of liquid: you move one ball at a time, so solutions take more moves, but the logic is identical. You will also see it called color sort, liquid sort, bottle sort or water color sort. If you enjoy these, you may also like our laser puzzle, where you place mirrors to guide a beam, or a slow round of Minesweeper. For something with no thinking at all, try the bubble popping game.
Frequently asked questions
How do you play water sort?
Tap a tube, then tap another to pour its top layer across. You can only pour onto the same color or into an empty tube, and only as much as fits. The puzzle is solved when every tube holds four layers of a single color.
Is there a trick to water sort puzzles?
Yes: keep an empty tube free for as long as you can, finish tubes that are nearly one color before starting new ones, and never pour a color into an empty tube while another tube already has that color on top. When you are stuck, look for the color with the most layers already near the tops.
Can a water sort puzzle be impossible?
A random shuffle can be, and so can a position you reach with the wrong pours. Every level here is checked by a solver before you see it, so it can always be finished from the start, and the game tells you when your pours have left no way out and how many moves 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 marks mean?
In hidden-color levels only the top layer of each tube shows its color. The layers 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 water sort and ball sort?
They are the same puzzle with different pieces. In ball sort you move one ball at a time; in water sort the whole top layer of one color pours at once, so you need fewer moves but have to think about what lands where.
Is there a daily water 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 water 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.