Cat Sudoku Online: Play Meowdoku Free in Your Browser

Cat sudoku is the casual name for a logic puzzle that keeps sudoku's one-per-line thinking and swaps the numerals for a grid of cats. The board is not a classic 9×9 number square. It is a smaller field of coloured regions, and the deduction comes from where those regions sit as much as from the rows and columns.

In practice a cat sudoku board asks you to place one cat in every row, one in every column and one inside each coloured area, with the extra condition that no two cats may touch, corners included. The first three rules talk about lines; the fourth one talks about the spaces between them, and it is what gives the puzzle its own character.

The name is loose, and it is meant to be. Cat sudoku is how people search for this kind of puzzle, so the phrase covers almost anything from a full number grid with cat symbols to a cat-shaped logic board like this one. What it reliably signals is a sudoku-style deduction problem with cats in the leading role. Meowdoku is our take on exactly that: the same cat sudoku rules, playable directly in a browser, with no app install and no account.

Start on a board and look at the coloured regions rather than the cats, because there are none on the grid yet. A cat sudoku board opens empty and hands you no clues at all, so the region shapes are the first thing to read.

Work region by region. Find the tightest one, count which of its cells are still legally free once you account for the rows, the columns and the no-touching rule, and place a cat when the answer is a single cell. Mark an X on every cell you can rule out, so the next decision is easier than the last.

The click cycle is short: a first click marks an X, clicking the same cell again places a cat, and a third click clears it. Undo steps back through your placements, Check reports a problem without giving away the answer, and the How to play dialog carries a hint written for that particular level.

When you would rather watch a puzzle come apart step by step, every level also has a written walkthrough with a video answer. Working one solution through by hand is the quickest way to see how the region, line and adjacency rules combine.

Much of the cat sudoku material online is written about the puzzle rather than playable. Meowdoku is the game itself: a board you can fill in, with the marking, checking and undoing that a real solve needs. It runs on a desktop, a tablet or a phone, and the page you are reading is a few clicks from an open board. None of that asks for a download, an account or a payment, and nothing is locked behind a level or a timer. The whole point of putting a puzzle in the browser is that it is always one click away when a few minutes open up.

The built-in puzzles are grouped into intro, easy, medium and hard, so there is a sensible place to begin if the format is new to you. They run from 4×4 boards up to 9×9, and a fresh daily puzzle is generated for each date if you want a reason to come back.

Because the puzzle is pure deduction, it also suits a quiet five minutes rather than a long session. A small board is a complete puzzle in miniature: the same three line-and-region rules, the same no-touching twist, and a finish you can reach before a coffee goes cold.