Queens puzzle solver facts at a glance
The Queens puzzle solver takes square boards from 5x5 to 11x11, checks whether the painted regions have no solution, exactly one or several, and explains the next move with one of four named logic rules. It is free, needs no account and runs in your browser.
| Board sizes | 5x5, 6x6, 7x7, 8x8, 9x9, 10x10 and 11x11, with as many colored regions as rows |
|---|---|
| Rules | One queen in every row, column and colored region; no two queens touch, not even diagonally |
| What you get | The full solution, or one hint at a time that places a queen or X marks and names the rule |
| Checks | Unpainted cells, the wrong number of regions, clashing queens, no solution and more than one solution |
| Known queens and X's | Optional: add the ones you already have and the solver and hints start from them |
| Speed | Under a fifth of a second on an 11x11 board, including boards with no solution |
| Price and setup | Free, no account, no download; runs in your browser |
How to use the Queens puzzle solver
Pick the board size, paint every colored region of your puzzle with its own color, and press Solve to see a crown on each queen, or Next step to get one move at a time with the reason behind it.
- Pick the board size. Count the rows of your puzzle: daily Queens boards are usually 7x7 to 11x11. The board has as many regions as rows.
- Paint the regions. Choose a color, then tap a cell or drag across several. A stroke that starts on a cell of the same color erases instead. Paint the small regions first, then use Fill empty cells for the last, biggest one.
- Add what you know (optional). With ♛ Queen or ✕ X selected, tap cells to add queens or X marks you already placed in your game.
- Press Solve or Next step. Solve shows every queen at once. Next step places one queen or a set of X marks and says which rule proves it; keep pressing to finish the board.
- Keep the answer. Copy the answer lists the queen in each row, and Copy board link saves a link that reopens this board with its solution.
The four logic rules behind the hints
Every hint uses the simplest of four rules that still makes progress, so the steps follow the way people solve these puzzles by hand.
- Last open cell. When a row, column or region has only one cell left where a queen can go, the queen goes there. Each queen then rules out its row, column, region and the eight cells around it.
- Region inside one line. When every open cell of a region lies in one row (or column), that region’s queen will fill the line, so every other cell of the line gets an X. The same works the other way round: a line whose open cells all lie in one region.
- Would empty another line or region. If a queen on a cell would rule out every open cell of some other row, column or region, that cell cannot hold a queen.
- Regions sharing lines. When two regions together fit in exactly two rows (or three regions in three rows, and so on), those regions use up the rows, so every other cell in them gets an X. The same holds for columns, and for lines that fit in the same number of regions.
Most daily puzzles fall to these four rules alone. If none of them applies, the hint shows one queen of the solution instead of guessing.
How the solver works
The solver searches for queens the way a careful player would: it always picks the row, column or region with the fewest open cells, tries a queen in each of them, and removes every cell that queen rules out. A line or region with no open cell left ends that branch at once, which keeps even an 11x11 board with no solution to a few thousand steps. The search stops after a second solution, so it can tell you whether your board has none, exactly one or several. The hints come from the same engine as our game Cat Nap, which uses exactly these rules. Everything runs in your browser.
Queens, Star Battle and Meowdoku
Queens is one name for a logic puzzle that has been around much longer: in puzzle books it is a Star Battle with one star per row, column and region. LinkedIn’s daily Queens game made it popular again, and cat-themed versions such as Meowdoku use the same rules with cats. This page is an independent solver and is not affiliated with LinkedIn or any of those games; the Meowdoku rules and tips guide walks through the same techniques with worked boards.
Frequently asked questions
What are the rules of the Queens puzzle?
The board is an N by N grid split into N colored regions. Place N queens so that every row, every column and every colored region holds exactly one queen, and no two queens touch, not even diagonally. A well-made puzzle has exactly one solution, and you can always find it by logic, without guessing.
Is this the LinkedIn Queens game?
No. Chaoschemy is not affiliated with LinkedIn. Queens is a classic logic puzzle, also known as one-star Star Battle, and the same rules appear in games such as Meowdoku. This solver works for any puzzle with these rules: copy the colored regions of your board and it finds the answer.
How do the step-by-step hints work?
Next step finds the simplest rule that moves the board forward, places the queen or the X marks it proves, and names the rule: last open cell in a row, column or region; a region that fits in one row or column; a cell that would leave another line or region empty; or a group of regions that fill the same number of rows or columns. Press it again for the following step, so you can learn the reasoning instead of only copying the answer.
Why does the solver say there is more than one solution?
The regions you painted allow the queens to be placed in two or more ways. A real Queens puzzle has exactly one solution, so this almost always means a cell was painted in the wrong color. The solver shows one solution and outlines the cells where the solutions differ, which is where to compare the board with your game.
Why does the solver say there is no solution?
No placement of queens fits the regions as painted, or the queens and X marks you added rule out the only answer. Check the colors cell by cell first, then clear your queens and X marks and solve again; a single cell in the wrong region is enough to make a board impossible.
Is the Queens puzzle solver free?
Yes. It is free, with no account and no download, and it runs in your browser. Boards up to 11 by 11 solve in a fraction of a second, and a board link keeps the regions in the link itself.