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Water Sort Puzzle (Color Sort)

Pour the colours until every bottle holds only one. Open the link and start sorting.

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No sign-up · No install · 100% free

Why play here

How to play water sort

You are given bottles with layers of mixed colours and two empty bottles. Tap one bottle then another to pour the top colour across — but only onto the same colour, or into an empty bottle, and only while there is room.

Keep pouring until every bottle contains a single colour and the board is clear. Treat the empty bottles as temporary workspace rather than somewhere to dump a colour, and try to move a colour only when it can go somewhere it will stay.

Also known as water sort, colour sort, or the ball / liquid sorting puzzle.

The order you pour in decides the game

Most lost boards are lost to sequencing, not to picking the wrong colour. These four rules set the order.

  1. Empty tubes are currency. You only get two. Spend one on a colour you have no plan for and your options vanish immediately. Use an empty tube when it enables a specific next move, and free it again as soon as you can.
  2. Move the thickest stack first. Three of the same colour stacked together travel in a single pour. It costs one move, exactly like shifting a single unit, and gains three times as much.
  3. Finish the tube that is nearly done. A tube filled with one colour is out of the way for good. Leave it half-finished and it keeps getting used as a dumping ground.
  4. Check what you are burying. Pouring B onto A means A is unavailable until B moves again. Asking "can I afford to cover this colour?" before each pour prevents most dead ends.

4, 6 and 8 colours

More colours means more tubes, but you still get only two empties. So the ratio of free space to possibilities gets worse quickly as the level rises.

When you get stuck

Every board is checked for a solution as it is generated, so an unsolvable level never appears. Being stuck means an earlier move can be taken back.

Undo lets you take several moves back, so retrace to the point where it went wrong rather than restarting. It is almost always the move where you first used an empty tube.

Frequently asked questions

Is it really free?
Yes. Every game is free and no account is needed.
Can I get an unsolvable board?
No. Every board is verified during generation, so if you are stuck the solution is still there — undo a few pours and free up an empty bottle.
Any strategy?
Never split a colour across two bottles if you can avoid it, and keep at least one bottle genuinely empty for as long as possible.