Cat Sudoku: Meowdoku Rules, Tips & Free Online Play

Cat Sudoku looks like the cutest puzzle on the internet, but it hides a sharp little logic engine. On Puzzit you can play it free as Cat Sudoku (Meowdoku-style): drop cats onto a colorful grid so that every row, every column and every colored region holds exactly one cat, and no two cats ever touch, not even corner to corner.

If you have searched for the Meowdoku rules, wondered why your cats keep “fighting”, or got stuck on an 8×8 Ultra board, this guide is for you. We cover how to play, the deduction tricks that solve almost every level without guessing, how Cat Sudoku compares with LinkedIn’s Queens game and classic sudoku, and the best free puzzles to try next.

Meowdoku Rules: How to Play Cat Sudoku

Every Cat Sudoku level is a square grid split into colored regions. The number of cats you must place equals the width of the grid, so a 6×6 board needs 6 cats and an 8×8 board needs 8. A valid solution follows three rules at the same time:

• One cat per row and one per column. Just like the “no repeats” rule in sudoku, but with cats instead of digits.
• One cat per colored region. Each patch of color, whether it is a big blob or a skinny strip, gets exactly one cat.
• No touching. Cats can’t be neighbors in any of the eight directions. Diagonal contact is the rule most beginners forget.

The controls

• Cat mode (the default): tap a square to place or remove a cat. The counter at the top shows how many you have placed, for example 3/6.
• × X mode: tap squares to mark them as “definitely no cat”. This is how you take notes, and it is the secret to solving harder boards.
• Fill X: fills every empty square with an X in one go. It is handy once your cats are placed, or after you reset a cluttered board.
• Lightbulb hint: places one correct cat for you. Reset arrow: clears the board so you can start again.

If two cats break a rule, the game outlines both in red and tells you the cats are fighting, so you can see right away which row, column, region or diagonal is the problem. Place the last valid cat and the level is solved. Every remaining square turns to X, and a Next Level button appears.

Cat Sudoku Tips and Tricks (Solve Without Guessing)

Good Cat Sudoku players almost never guess. They use X marks to cross off squares that can’t hold a cat until only one choice is left. These are the Meowdoku tips and tricks that do most of the work.

1. Start with the smallest region

A region with only one or two squares gives you very few options. A one-square region is a free cat. A two-square region tells you the cat is in one of two spots, and that alone often eliminates several squares around it, as the next tricks show.

2. Cross off everything a cat “sees”

The moment you place a cat, X out its whole row, its whole column, its diagonal neighbors and the rest of its region. On a 6×6 board, a cat in the middle of the grid removes 14 squares through rows, columns and diagonals alone, before you even count its region. A corner cat removes 11. On an 8×8 Ultra board the numbers rise to 18 and 15. That is why one correct cat often unlocks the next two.

3. Use the shape of a region to find shared X’s

You don’t have to know where a cat goes to eliminate squares. Look for squares that every possible position in a region would rule out:

• Two cells side by side (a domino): whichever one gets the cat, the two squares directly above and the two directly below can never hold a cat.
• Three cells in a straight line: the squares directly above and below the middle cell are always eliminated.
• An L-shape of three cells: the square inside the bend of the L is always eliminated, and so are the two squares right behind the corner cell, one opposite each arm.

4. Regions trapped in one row or column

If a region sits entirely inside a single row, that region’s cat must be in that row. So every other square in the row, outside the region, gets an X. The same logic works for columns, and it scales: if two regions together fit inside exactly two rows, those two rows are “used up” by those two regions, and every other square in those rows can be crossed off. Spotting this pattern is the biggest jump from Normal to Ultra.

5. Any 2×2 block holds at most one cat

Any two squares in a 2×2 block share a row, a column or a diagonal touch, so a 2×2 block can never hold two cats. Use this when a region is squeezed into a small corner: if a region fits completely inside one 2×2 block, that block’s cat belongs to that region, and the parts of other regions in the same block are out.

6. Use hints as a lesson, not a crutch

Stuck on a Hard board? Tap the lightbulb hint once and then ask yourself why the cat belongs there. Usually it is one of the patterns above that you missed. Learning to see it is how you stop needing Meowdoku hints at all.

Cat Sudoku vs Queens vs Classic Sudoku

Cat Sudoku belongs to a puzzle family called Star Battle. According to the Puzzle Wiki, Star Battle was invented by Hans Eendebak and debuted at the 2003 World Puzzle Championship. The one-star version, with one item per row, column and region, is the same rule set LinkedIn uses for its daily Queens game, and puzzle champion Thomas Snyder helped provide puzzles for its launch. Meowdoku-style games swap the stars or crowns for cats. Here is how they compare with classic Sudoku:

So if you came here looking for an unlimited Queens game or a way to play the Queens game online more than once a day, Cat Sudoku scratches exactly the same itch. The strategies above work in all three cat, crown and star versions.

There is also a mobile app called Meowdoku, made by Oakever Games, that uses the same cat-placement rules. Android Central’s review of it praised how addictive it is but criticized the frequent ads. Puzzit’s version runs in any browser, on phone or desktop, with nothing to install.

Why Cat Sudoku Is So Satisfying

Most logic puzzles reward you only at the very end. Cat Sudoku rewards you all the way through: every cat you place wipes out a whole cross of squares, the board shrinks, and the next move appears. Boards are small enough for a coffee break, and three difficulty tiers give you room to grow. Normal’s 6×6 grids teach the basic rules, Hard’s 7×7 boards make you use region shapes, and Ultra’s 8×8 boards require the “trapped regions” trick.

If you like this style of no-numbers deduction, you will probably enjoy our roundup of math and logic puzzles and the wider list of brain teaser puzzles.

Games Like Meowdoku to Play Next

Finished today’s cats? These free Puzzit games use the same kind of grid logic:

• Emojidoku: sudoku with emojis instead of numbers, a natural next step after Cat Sudoku.
• Mini Sudoku: a smaller, faster sudoku for short sessions, with the same small-grid feel.
• Shikaku: split the grid into rectangles that match the clue numbers. It is region logic in reverse.
• Daily Minesweeper: another “where can’t it be?” puzzle, built around eliminating hidden mines.
• Zip Dots: connect numbered dots in order with one continuous path, a great warm-up for spatial logic.

For more ideas, see our guide to the best puzzle games or try something numeric like Mathle, the math Wordle game.

Cat Sudoku FAQ

What are the rules of Meowdoku?

Place one cat in every row, every column and every colored region. Cats may not touch each other, including diagonally. When all cats are placed without breaking a rule, the level is solved.

Is Meowdoku the same as sudoku?

Not quite. It borrows sudoku’s “one per row and column” idea, but you place cats instead of numbers, colored regions replace 3×3 boxes, and cats cannot touch. It is closer to Star Battle and LinkedIn’s Queens puzzle.

Where can I play cat sudoku online for free?

You can play Cat Sudoku free on Puzzit in any web browser on phone, tablet or computer. There is nothing to download and no account needed.

Is Cat Sudoku the same as the Queens game?

The rules are the same as the one-per-row, column and region version of Queens: one item per row, column and region, with no touching. Cat Sudoku uses cats instead of crowns and lets you play level after level instead of one puzzle a day.

How do I get Meowdoku hints?

In Puzzit’s Cat Sudoku, tap the lightbulb button to place one correct cat. Before you use it, try the tricks in this guide: start with the smallest region, X out everything a cat sees, and look for regions trapped in a single row or column.

What do Normal, Hard and Ultra mean?

They are the board sizes. Normal is 6×6 with 6 cats, Hard is 7×7 with 7 cats, and Ultra is 8×8 with 8 cats. Bigger boards have more regions, so you need more of the advanced elimination tricks.

Ready to Place Some Cats?

Open Cat Sudoku on Puzzit, start on Normal, and try to solve a level without using a single hint. Then move up to Ultra and see how fast you can find the trapped regions.