How do you play a ball sort puzzle?

Choose a tube with a ball on top, then choose a destination tube. The top ball moves if the destination is empty, or if its top ball is the same color and it holds fewer than four balls. Moves onto a different color, into a full tube, from an empty tube or back onto the same tube are refused and leave every tube unchanged. The puzzle is solved when every nonempty tube holds four balls of one color.

Is every puzzle solvable?

Yes. Each seeded deal is checked by a solver before it is offered, and the solution it finds is replayed move by move under the same rules to confirm it ends with every tube sorted. A deal the solver cannot finish is skipped and the next deal from the same seed is tried. The same colors and seed always rebuild the same puzzle. Your own moves can still reach a position with no solution: when no legal transfer is left the page says so, a hint reports when no sequence of legal transfers solves the position, and Undo or Reset gets you back.

What do hints and the solution certificate do?

Hint searches from your current position and marks one transfer that keeps the puzzle solvable, labelled from and to on the tubes. It suggests the move; you still make it. Show solution certificate lists a complete solution from the starting position. Either one turns an unfinished run into assisted practice: you can still finish the puzzle, but it cannot share a score. Showing the certificate after you have solved the puzzle keeps your result.

How is the challenge scored?

The challenge is a seeded original puzzle with four colors, four balls each, tube capacity 4 and two spare tubes. Score is max(0, 1000 minus final retained transfers), so higher is better. Undo removes a transfer from the count, and Reset before solving returns the count to zero. Hints, the solution certificate, restored or imported progress and a puzzle this browser has already opened stay practice. Scores are self-reported.

What happens when someone opens a challenge link?

The page shows the shared score and the fixed rules with a Start same challenge button; nothing starts automatically. After they solve the same puzzle, it shows both scores, the signed difference and whether their score is better, tied or lower, plus a new link carrying their own score. Copy challenge link, Share challenge and Download result card are available. Besides the tool name, the link holds only the seed, the four-color setting and the score, never moves or answers.

Does it save my progress?

Yes, in this browser. The current puzzle, its retained transfers and whether it was assisted are saved locally, and an unfinished puzzle you have started is restored as practice when you return. Download puzzle JSON or Copy puzzle JSON exports the original deal and your transfer history, without the solution. Loading an export rebuilds the puzzle from its seed and replays every transfer; an export that does not match is refused and your current puzzle is kept.

Can I play with a keyboard or on a phone?

Yes. Every tube is a button: Tab to it and press Enter or Space to pick it. While a tube has focus, number keys pick tubes by number, arrow keys move between tubes and Escape clears a choice. Each tube's label reads its balls from bottom to top by color name, and every ball also shows a letter and a pattern, so colors are never told apart by hue alone. On narrow screens the tubes wrap into rows of targets at least 44 pixels wide, and with reduced motion set, balls move without animation.

Ball Sort Puzzles

Sort colored balls until every tube holds four of one color. Each original puzzle is a seeded deal of 2 to 6 colors, four balls per color, in tubes that hold four, plus two empty spare tubes. A move takes the top ball into an empty tube or onto a matching color in a tube with space; anything else is refused and nothing changes. Every puzzle is offered only after a solver finds a solution and a replay of that solution under the game rules confirms it. Undo, reset, hints, the full transfer history and a saved or exported JSON copy are built in, and a fresh, unassisted 4-color solve can share a scored challenge for the same puzzle.

TubesNo puzzle open

Preparing an original puzzle.

Puzzle2 to 6 colors · 4 balls each · 2 spare tubes

ColorsSeed

Seeds are whole numbers from 0 to 4294967295. A fresh 4-color puzzle solved without hints or the certificate can be shared as a scored challenge.

Colors in play

Red, checks
Blue, horizontal stripes
Yellow, dots
Green, diagonal stripes

Retained transfers

No transfers yet.

Save and load

Progress saves in this browser. Export the puzzle and its transfers as JSON to continue elsewhere; imported progress is practice.

Paste a puzzle export

Load JSON file

Preparing an original puzzle.

Legal transferone top ball
A Red top ball can go into an empty tube, or onto another Red top ball in a tube holding fewer than 4 balls.
Refused transfertubes unchanged
Onto a different color, into a full tube, from an empty tube or back onto the same tube: the move is refused and nothing changes.
Solvedfour of one color
Every nonempty tube holds four balls of one color. With 4 colors that is 4 sorted tubes and 2 empty ones.

Common questions

How do you play a ball sort puzzle?: Choose a tube with a ball on top, then choose a destination tube. The top ball moves if the destination is empty, or if its top ball is the same color and it holds fewer than four balls. Moves onto a different color, into a full tube, from an empty tube or back onto the same tube are refused and leave every tube unchanged. The puzzle is solved when every nonempty tube holds four balls of one color.
Is every puzzle solvable?: Yes. Each seeded deal is checked by a solver before it is offered, and the solution it finds is replayed move by move under the same rules to confirm it ends with every tube sorted. A deal the solver cannot finish is skipped and the next deal from the same seed is tried. The same colors and seed always rebuild the same puzzle. Your own moves can still reach a position with no solution: when no legal transfer is left the page says so, a hint reports when no sequence of legal transfers solves the position, and Undo or Reset gets you back.
What do hints and the solution certificate do?: Hint searches from your current position and marks one transfer that keeps the puzzle solvable, labelled from and to on the tubes. It suggests the move; you still make it. Show solution certificate lists a complete solution from the starting position. Either one turns an unfinished run into assisted practice: you can still finish the puzzle, but it cannot share a score. Showing the certificate after you have solved the puzzle keeps your result.
How is the challenge scored?: The challenge is a seeded original puzzle with four colors, four balls each, tube capacity 4 and two spare tubes. Score is max(0, 1000 minus final retained transfers), so higher is better. Undo removes a transfer from the count, and Reset before solving returns the count to zero. Hints, the solution certificate, restored or imported progress and a puzzle this browser has already opened stay practice. Scores are self-reported.
What happens when someone opens a challenge link?: The page shows the shared score and the fixed rules with a Start same challenge button; nothing starts automatically. After they solve the same puzzle, it shows both scores, the signed difference and whether their score is better, tied or lower, plus a new link carrying their own score. Copy challenge link, Share challenge and Download result card are available. Besides the tool name, the link holds only the seed, the four-color setting and the score, never moves or answers.
Does it save my progress?: Yes, in this browser. The current puzzle, its retained transfers and whether it was assisted are saved locally, and an unfinished puzzle you have started is restored as practice when you return. Download puzzle JSON or Copy puzzle JSON exports the original deal and your transfer history, without the solution. Loading an export rebuilds the puzzle from its seed and replays every transfer; an export that does not match is refused and your current puzzle is kept.
Can I play with a keyboard or on a phone?: Yes. Every tube is a button: Tab to it and press Enter or Space to pick it. While a tube has focus, number keys pick tubes by number, arrow keys move between tubes and Escape clears a choice. Each tube's label reads its balls from bottom to top by color name, and every ball also shows a letter and a pattern, so colors are never told apart by hue alone. On narrow screens the tubes wrap into rows of targets at least 44 pixels wide, and with reduced motion set, balls move without animation.

A move takes one top ball to an empty tube or onto a same-colored top ball in a tube with free space. Solved means every nonempty tube holds four balls of one color, and every offered puzzle carries a solution certificate that is replayed before play. Puzzles are original seeded deals, not a copied level bank, with no claimed human difficulty; letters and patterns supplement hue.