# Meowdoku — Full Reference

> Meowdoku is a free, browser-based cat logic puzzle in the style of Sudoku and the LinkedIn Queens puzzle. Place one cat in every row, column, and color region of an N×N grid without letting any two cats touch — not even diagonally. It is pure logic with no numbers, no account, and no download. Site: https://meowdoku.run

This document is a complete plain-text reference to Meowdoku for language models and answer engines.

## What is Meowdoku?

Meowdoku is a free logic puzzle where you place cats on a colored grid. It borrows the deduction of Sudoku and the exact ruleset of the Queens puzzle (popularized by LinkedIn), but swaps numbers for cats, so it stays approachable even for people who find Sudoku intimidating. Despite the "cat Sudoku" nickname, you never write numbers and you do not fill in the whole grid — you place a few cats in exactly the right spots using logic alone. Every board has a single solution reachable by reasoning; there is never any guessing.

## The goal

Place a single cat in every row, every column, and every colored region, and make sure no two cats ever touch. On a 6×6 board that means just six cats in total; most cells stay empty. When all cats are placed correctly, the puzzle is solved.

## The rules

1. Every row contains exactly one cat.
2. Every column contains exactly one cat.
3. Every colored region contains exactly one cat.
4. No two cats may touch — not horizontally, vertically, or diagonally. Once a cat is placed, all eight surrounding cells are off-limits.

## How Meowdoku differs from Sudoku

- No numbers and no math. You place cats, not digits — it is pure pattern logic.
- You do not fill the grid. Sudoku fills every cell; Meowdoku places just one cat per row, column, and region, so most cells stay blank.
- Cats cannot touch. This adjacency rule (including diagonals) does not exist in Sudoku and is the heart of the puzzle. It comes from the Queens puzzle, which Meowdoku is built on.
- Every board is generated with a guaranteed single solution you can always reach by reasoning — you never have to guess.

## Controls

Tap a cell to cycle through three states: empty, then ✕ (your own note that a cat cannot go there), then a placed cat, then empty again. The ✕ mark is the built-in pencil (draft) mode: it is only a memory aid and is not checked against the rules; only cats are.

You can reset the board at any time, and in endless mode start a new puzzle. After losing all three hearts you can retry the same board. After a solve you can share your result (solve time and hearts left) on social apps or copy it.

## How you win and lose

- Win: place the full set of cats with every row, column, and region holding exactly one, and no two cats touching.
- Lose: you have three hearts. Placing a cat that breaks a rule costs one heart, and losing all three ends the round — but you can retry instantly.

## Reading the board

- Lives (hearts): you start each puzzle with three. Each rule-breaking placement removes one.
- Timer: how long you have spent on the current puzzle. Solving sets your best time.
- Cats placed: how many cats you have placed out of the total needed to finish the board.

## Game modes

Both modes are tabs on the same board on the homepage (https://meowdoku.run/#play and https://meowdoku.run/#daily). Same rules, same three hearts; the tab decides where the puzzles come from.

- Endless: an unlimited stream of freshly generated puzzles in three difficulties. Every "New puzzle" is a fresh seed, verified to have a single solution the moment it is made, so a repeat is practically impossible. Switch between 6×6, 7×7, and 8×8 at any time. Your best time is saved per difficulty in your browser.
- Daily: three fixed boards per day — one Easy, one Normal, one Hard — generated from the date, so refreshing does not change them and everyone worldwide solves the same set. It resets at midnight UTC. Your best time for each daily board is saved in your browser.

## Difficulty levels

- Easy: a 6×6 board with six cats. Best for learning the rules or warming up.
- Normal: a 7×7 board with seven cats. A balanced everyday challenge.
- Hard: an 8×8 board with eight cats. Built for a real workout.

Board size drives the challenge — every step up adds a row, a column, a region, and one more cat.

## Solving tips

- Start where you have the fewest choices — small regions, corners, and tight rows or columns.
- After placing a cat, mark an ✕ across its whole row, column, region, and the eight cells around it. Clearing those squares usually exposes the next forced move.
- If a region, row, or column has only one open cell left, that cell must be a cat. Chains of these forced placements tend to solve the whole board.
- You never need to guess; if you are stuck, look for the most constrained line or region.

## Advanced strategy

These techniques (covered in full at https://meowdoku.run/tips) help experienced players solve faster and stop losing hearts:

- Most-constrained-first: always work the smallest region or the tightest row or column before anything else. A certain move never costs a heart.
- Region line-locks: when a region's only open cells all sit in one row or column, that line is reserved for it, so every other region's cell in that line can be eliminated — even before you know which cell holds the cat.
- Adjacency cascades: each placed cat blocks the eight cells around it, which often leaves a neighbouring region with a single legal square, forcing the next cat in a chain.
- Negative space: when stuck, ask where a cat cannot go rather than where it can, and mark those cells; empty cells carry as much information as placed cats.
- Locked pairs: if two regions can each only place their cat in the same two rows (or columns), those two lines are locked between them and shut out every other region.
- The diagonal-touch trap: the most common mistake is two cats on different rows and columns that still touch at a corner. Diagonal contact breaks the no-touch rule and costs a heart.
- Pre-move check: before each placement, confirm the row, the column, the region, and all eight surrounding cells (corners included) are clear.
- Endgame sweep: with a few cats left, match each remaining region against the rows and columns no cat has used yet to force the final placements.

## When you are stuck

Every board has exactly one solution, so being stuck always means one elimination is missing. Run these steps in order and stop at the first one that gives you a cat:

1. Re-mark the board: for each placed cat, cross out its row, its column, the rest of its region, and the eight cells around it. Most stuck boards are missing a diagonal ✕.
2. Count open cells per region. One open cell means a forced cat.
3. Look for a line-lock: if a region's open cells all sit in one row or column, cross that line out for every other region and re-count.
4. Match leftovers: pair the rows and columns with no cat yet against the regions still empty. A region that can reach only one unused line is forced.
5. Suspect an early cat: if nothing moves, a cat placed "by feel" is probably wrong. Remove the least certain one and re-run the list.

## Hints

The site has no reveal button. A useful hint names one cell and the one rule that forces it, and the ✕ mark lets you produce that yourself: cross out everything the current cats forbid, and the cell left alone in its region is the hint. If you use a full reveal elsewhere, replay the board without it afterwards.

## Meowdoku levels (mobile app)

The Meowdoku mobile app is organised as a numbered level campaign; Meowdoku.run does not reproduce those boards and does not publish per-level answers. Details: https://meowdoku.run/levels

- There is no fixed, published total. The campaign grows with app updates, and players report level numbers well past 100.
- A level number is a difficulty slot, not one fixed board: players comparing the same number often see different layouts, and a level can change after a reinstall. An online "answer" only helps if the regions match cell for cell; the deduction method always transfers.
- Difficulty tracks board size more than level number. Sizes verified from public walkthrough videos (June 2026): level 20 is 8×8, 22 is 7×7, 23 is 6×6, 24 is 7×7, 30 is 9×9, 40 is 8×8, 53 is 10×10, 55 is 9×9, 58 is 10×10, 60 is 9×9, 103 is 10×10. The app may differ if the campaign has been reshuffled since.
- Roughly: 6×6 is a warm-up, 7×7 and 8×8 are an everyday challenge where line-locks matter, and 9×9 and 10×10 often need several deductions (frequently a locked pair) before the first certain cat.
- Endless mode on this site tops out at 8×8, which covers the techniques a 10×10 needs; bigger boards chain more of them.

## Mobile apps vs. this web version

Several Meowdoku mobile apps exist; Meowdoku.run is an independent browser version and is not affiliated with any of them.

- Install: the apps are downloaded from an app store; the web version opens in the browser with nothing to install.
- Works on: the apps run on Android phones and tablets and Windows; the web version runs in any modern browser on phone, tablet, or desktop.
- Price: the apps are free with optional in-app purchases; the web version is free with no purchases and no account.
- Hearts: both allow three mistakes.
- Offline play: the apps work offline; the web version needs a connection.
- Daily puzzle: the apps have one with global leaderboards; the web version has three daily boards (Easy, Normal, Hard) and keeps your times on your device.
- Puzzles: the apps have a numbered level campaign that keeps growing; the web version has unlimited generated boards plus the daily set.

## Frequently asked questions

- Is Meowdoku free? Yes. It is completely free to play in your browser — no account, no download, and no in-app purchases.
- How is Meowdoku different from Sudoku? It shares the same deductive feel, but you place cats instead of writing numbers. Each row, column, and colored region needs exactly one cat, and cats can never touch. There is no arithmetic involved.
- Do I need to be good at math? No. It is pure logic — there are no numbers to add and no calculations.
- Where should a beginner start? Choose Easy (a 6×6 board) and look for the smallest colored region or the most constrained row or column. Place a cat there first, then work outward.
- Do I need to install anything? No. It runs in mobile browsers, tablets, and desktop with nothing to download or unblock.
- Where is the pencil or draft mode? It is built into the board: tap a cell once to leave an ✕ note, and tap again to place a cat. The ✕ never changes the solution.
- Is there a new puzzle every day? Yes. The Daily tab gives everyone the same three boards each day — one Easy, one Normal, one Hard — so you can compare solve times.
- Do I ever have to guess? No. Every board has exactly one solution reachable through logic alone.
- What time does the daily puzzle reset? At midnight UTC; it changes at the same moment for everyone.
- Will I get the same endless puzzle twice? It is extremely unlikely, because each board is generated fresh from a random seed.
- How many levels does Meowdoku have? Endless mode here is not capped. The mobile app's numbered campaign has no fixed published total and keeps growing with updates.
- Does this site have Meowdoku level answers? No. It does not copy the app's boards; it teaches the deduction method instead, which works on any layout.

## About and policies

Meowdoku is a small, independent project built by a developer who loves logic puzzles. It is not affiliated with, endorsed by, or sponsored by any "Meowdoku" mobile app or its publishers; product names are used only to describe the style of puzzle.

- Home: https://meowdoku.run/
- Play (endless): https://meowdoku.run/#play
- Daily puzzle: https://meowdoku.run/#daily
- Levels explained: https://meowdoku.run/levels
- How to Play: https://meowdoku.run/how-to-play
- Tips & Strategy: https://meowdoku.run/tips
- About: https://meowdoku.run/about
- Contact: https://meowdoku.run/contact (contact@meowdoku.run)
- Privacy Policy: https://meowdoku.run/privacy
- Terms of Service: https://meowdoku.run/terms