Cat Doku
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Daily Cat Doku
A new deal every day, the same for everyone. Your first try is the one that counts.
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Cat Doku
One Cat per Color, Row and Column. Free Online
Play Cat Doku free online in your browser, a cat sudoku in the style of Queens and Star Battle, with no download or account needed.
Cat Doku is a free cat sudoku, a logic puzzle in the style of Queens and Star Battle: a square grid cut into colored regions, and a handful of cats that need hiding. Every color gets exactly one cat, every row gets one, every column gets one, and no two cats may touch, not even kitty-corner. There are no numbers to add up and nothing to memorize. Every puzzle has a single solution you can reach by logic alone, so the fun is in spotting the one square that has to be a cat and watching the rest of the board fall into place. Play it free here at CardAndPuzzle.com, in your browser on a PC or a phone, with no download or sign-up.
How Do You Play Cat Doku?
There are four rules, and the whole puzzle follows from them:
- One Cat per Color: The board is split into colored regions, with as many colors as there are rows. Each region hides exactly one cat.
- One Cat per Row and Column: A 7x7 board needs seven cats, one in every row and one in every column.
- Cats Never Touch: No two cats can be neighbors, not side by side and not diagonally. Diagonal neighbors are called kitty-corner, and they count as touching.
- Winning: Place every cat correctly and the puzzle is solved.
Tap a square to put an X on it, your note that no cat can live there. Double-tap, press and hold, or right-click to place a cat. Drag across the board to mark a whole line of squares in one go.
Can Every Cat Doku Puzzle Be Solved Without Guessing?
Yes. Every puzzle is built to have exactly one solution, and each one is checked by a solver to make sure logic alone can finish it. Boards that would need a guess are thrown away before you ever see them, and every puzzle is checked again when it loads.
- Easy: The answers come from one line at a time, like a color with only one square left.
- Normal: You start asking what a cat in a square would do to the rest of the board, for example leave another color with nowhere to go.
- Hard: Two or three colors that are squeezed into the same two or three rows or columns, which clears those lines for everyone else.
- Expert: Following a chain of consequences to a dead end, to prove a square cannot hold a cat.
The journey starts on small 5x5 boards, with the first puzzle teaching you the rules on the board itself, and grows through 6x6, 7x7 and 8x8 to 9x9 and 10x10. Puzzles come one after another in order, and the journey never runs out.
How Do Tries and Hints Work?
- Every Cat Is Checked: When you place a cat, the game tells you right away if it is wrong. A wrong cat leaves a red mark on its square. If it clashes with a cat already on the board, the game shows you which rule it broke.
- Three Tries: Each wrong cat costs one of three tries. Run out and you can replay the puzzle from the beginning. There is no undo button, so place a cat only when you can say why it belongs there.
- X Marks Are Free: Your X marks are notes, not answers, so they are never checked and never cost anything.
- Hint Explains Itself: Hint shows the next logical step and tells you why in a sentence that stays on screen. It might lift an X you placed by mistake, mark squares that are ruled out, or walk you through a deduction.
- Find a Cat: When you are truly stuck, this places one correct cat, choosing one the board already forces where it can.
- 5 Free of Each: You get 5 free hints and 5 free cats, and you can earn more by watching a short ad.
- Perfect Clears: Solve a puzzle without losing a try and it counts as a perfect clear, with bonus XP toward your level.
- Picks Up Where You Left Off: Your board is saved as you play, so a half-solved puzzle is still half-solved when you come back.
What Are the Best Cat Doku Strategies?
- Start with the Smallest Color: A region of two or three squares has very few places for its cat. Small regions are usually the way in.
- Cross Out Around Every Cat: As soon as a cat is placed, mark its whole row, its whole column, its whole color and the eight squares around it. A tidy board makes the next step easy to see.
- Look for Colors Stuck in One Line: If every square of a color sits in the same row, that color's cat is in that row, so no other color can use it. The same goes for columns.
- Count Colors Against Lines: If two colors fit entirely inside the same two rows, those two rows belong to them. Every other square in those rows can be crossed out.
- Test a Square in Your Head: Ask what would happen if a cat sat there. If it would leave another color with no legal square, it cannot be a cat.
- Mark, Don't Guess: X marks cost nothing and wrong cats cost a try. Only place a cat when you can say why it has to be there.
Why Play Cat Doku Here?
- No Guessing, Ever: One solution per puzzle, every puzzle verified to be solvable by logic alone.
- No Timer to Race: There is no clock on screen and no score while you play. Take as long as you like.
- Free in Your Browser: No app store, no download and no account needed. It works on a PC, Mac, Chromebook, tablet or phone.
- Mouse or Touch: Tap and double-tap on a phone, click and right-click on a computer. Both play the same game.
- Colors You Can Tell Apart: The region colors are fixed and chosen to stay distinct for players with color blindness, whichever theme you use.
- Sits on Your Theme: The board sits on whichever of our themes you are using, while the region colors stay the same so they never get confused. Pick a theme on the themes page.
More Free Logic Puzzles
Cat Doku is one of our free puzzle games. If you like puzzles that never ask you to guess, Minesweeper makes the same promise in its Journey mode, and Arrows hands you a jammed board that is always clearable. For a card game built on pure planning, try FreeCell Solitaire.
Frequently Asked Questions
What is Cat Doku?
Cat Doku is a logic puzzle played on a square grid divided into colored regions. Your job is to hide cats so that every color, every row and every column holds exactly one cat, and no two cats ever touch, not even diagonally. A 7x7 board has seven colors and needs seven cats. Place the last one correctly and the puzzle is solved. It is a free puzzle in the same family as Queens and Star Battle, with cats instead of queens or stars.
How do you play Cat Doku?
Tap a square to mark it with an X, a note to yourself that no cat can go there. To place a cat, double-tap the square, press and hold it, or right-click it with a mouse. You can also drag across the board to mark a whole run of squares at once. Rule out squares with X marks until only one spot is left for a color, a row or a column, then put the cat there.
What does kitty-corner mean in Cat Doku?
Kitty-corner means diagonally across from something. In Cat Doku, cats cannot sit next to each other in any direction, including diagonally. So once you place a cat, all eight squares around it are ruled out, along with the rest of its row, its column and its color.
Do you ever have to guess in Cat Doku?
No. Every puzzle has exactly one solution, and each one is checked by a solver to make sure it can be finished by logic alone before you see it. Harder boards ask for longer chains of reasoning, but there is always a next step you can prove.
What happens if I place a cat in the wrong square?
Each cat is checked the moment you place it. A wrong cat leaves a red mark on that square and costs one of your three tries. If it clashes with a cat you have already placed, the game also points out which rule it broke. If all three tries are gone you can replay the puzzle from the start. There is no undo button, but your X marks are never checked, so you can note anything you like without risk.
How big do Cat Doku puzzles get?
The first puzzles are small 5x5 boards, and the very first one walks you through the rules on the board itself. The grids grow to 6x6, 7x7 and 8x8 as you go, and later puzzles reach 9x9 and 10x10. Every puzzle is labelled Easy, Normal, Hard or Expert, depending on the hardest piece of reasoning it needs.
Is Cat Doku the same as the Queens or Star Battle puzzle?
It is the same kind of puzzle. Star Battle, the Queens puzzle and Cat Doku all ask for one piece in every row, every column and every colored region, with no two pieces touching, not even diagonally. In Cat Doku the pieces are cats, which is where the name cat sudoku comes from. It is also a close cousin of Sudoku, since both are about placing one of each thing in every line, but there are no numbers to add up or memorize.
How do you solve a Cat Doku puzzle?
Start with the smallest colored region, because it has the fewest places for its cat. Every time you place a cat, cross out its row, its column, its color and the eight squares around it. Then look for a color whose squares all sit in one row or column, since that line now belongs to that color and every other square in it can be crossed out. Repeat until each color has a single square left.
Can I play Cat Doku on my phone?
Yes. Cat Doku runs in the browser on phones, tablets, Chromebooks and computers. On a touch screen you tap for an X and double-tap or press and hold for a cat, and on a computer you click for an X and right-click for a cat.
Are there hints in Cat Doku?
Yes, two kinds. Hint shows you the next step and explains it in a sentence: it might clear a wrong X, mark squares that are ruled out, or point out a deduction you missed. Find a Cat places one correct cat for you. You get 5 free uses of each, and after that you can earn more by watching a short ad.
Is Cat Doku free to play?
Yes. Cat Doku on CardAndPuzzle.com is free and runs in your browser on a PC, Mac, Chromebook, tablet or phone. There is nothing to download and no account needed, and a puzzle you are in the middle of is saved on your device, X marks and all. Sign in if you like to keep your progress on every device.
Is there a daily Cat Doku puzzle?
Yes. Every day at midnight Pacific time, Cat Doku gets one new puzzle that everyone plays. Your first try is the one that counts, and replays are practice. The board ranks by fastest finish, and you can see where you stand against the people you follow, your league of twenty players at your level, and everyone. The Card & Puzzle regulars, sixteen computer players who are always marked, fill any empty league seats. Find today's deal in the strip under the game, on Daily, and on the Cat Doku leaderboard.
