Catdoku

A sudoku-style logic puzzle where the numbers are cats. Place exactly one cat in every row, every column and every colored region — and no two cats may touch, not even diagonally. Free, no download, works on desktop and mobile.

Playable below Free - no sign-up Logic puzzle Daily challenge ~5 min per level

Loads the full browser build from games.azgames.io — starts on the numbered-level title screen.

Playing: games.azgames.io/catdoku Open in new tab

The rules

  1. 1
    One cat per row

    Every horizontal row ends the puzzle holding exactly one cat.

  2. 2
    One cat per column

    Same rule vertically — no column may hold two cats.

  3. 3
    One cat per color region

    The grid is split into irregular colored zones; each zone gets exactly one cat.

  4. 4
    Cats never touch

    No two cats may sit in neighboring squares — including diagonals. On a 6×6 board that means six cats, all isolated.

Controls and modes

  1. 1
    Tap once for an X

    An X marks a square where no cat can go — your main working tool. Most of a solve is X marks.

  2. 2
    Tap again to place the cat

    A second tap on the same square swaps the X for a cat; a third tap clears the square.

  3. 3
    Spend fish on hints

    Correct solves earn fish, the in-game hint currency. A wrong cat can cost you a fish, so deduce — don't guess.

  4. 4
    Unlock extras as you climb

    A daily challenge opens around level 21, and Double Cats mode — two cats per line — unlocks from level 30. There's a leaderboard under an auto-generated nickname.

Starter tactic: find the smallest colored region first and work out where its cat can go. The moment a cat lands, X out its entire row, column, region and the ring of eight surrounding squares — those crosses usually make the next placement obvious.

Where else it lives

Official web version

The original Catdoku by ONLYDRK Studio is at anul.space/catdoku, with a complete written rules guide. The embed above is a licensed HTML5 host of the same game.

Mobile apps

Catdoku also exists as a mobile app if you want it offline — the rules are identical, so anything you learn here carries over.