Free to play in your browser — no install, no sign-up.
PetDoku
Find the hidden pets — a pure logic puzzle.
PetDoku is a logic puzzle about working out where the pets are hiding. Every board is divided into colored regions, and exactly one pet belongs in each region — and in each row and each column. Pets are shy: no two of them may sit next to each other, not even diagonally.
Game overview
What is PetDoku?
There is no guessing. Every one of the 10,000 stages is checked by a solver so that it can be reached by reasoning alone. Five difficulties take you from a gentle 5x5 board up to a 12x12 challenge, with hints ready whenever you want one.
At a glance
- Tap a square once to mark it with X — that is how you rule places out.
- Double-tap a square (or press and hold) to place a pet there.
- One pet per colored region, per row and per column — and no two pets may touch, diagonals included.
- You have three hearts. Placing a pet where the logic rules it out costs one.
The rules in one minute
A PetDoku board is a square grid cut into colored regions, and there are as many regions as there are rows. Your job is to place one pet in every region, one pet in every row and one pet in every column. The last rule is what makes it interesting: no two pets may touch, not even at a corner.
Each board has exactly one answer, and every one of them was checked by a solver so that it can be finished by reasoning alone. Above the board, three small rule cards remind you of the rules: one pet per color, one per row and column, and keep pets apart. If you break one of them, that card gives a little shake.
Controls
Tap a square to mark it with an X. Tap it again to clear the mark.
Double-tap a square, or press and hold it for half a second, to place a pet.
Drag across several squares to mark them all with X in one go. If you start the drag on an X, the drag erases X marks instead.
A pet that has been placed stays put, so a stray tap cannot knock it off the board.
Double-tapping speed differs a lot from person to person. The tutorial measures how quickly you tap and widens the window if you need it, and the game keeps adjusting while you play. If double-tapping still feels awkward, press and hold works exactly the same way.
Hearts and mistakes
Because there is only one answer, the game knows right away when a pet goes in the wrong place. That square turns into a red X, which cannot be cleared, and you lose one of your three hearts. X marks never cost anything, so use them freely.
When the last heart is gone you can start the same board again from scratch. In the mobile apps you can also watch a short ad to refill your hearts and carry on with the board as it is. Your board is saved as you play, hearts included, so leaving the game and coming back later will not quietly refill them.
Five difficulties, 10,000 boards
Every difficulty has 2,000 boards and keeps its own progress, so you can move between them whenever you like.
5x5 for the first 250 boards, then 6x6.
mostly 7x7, with some 6x6 boards early on.
8x8.
9x9.
12x12, for long sessions.
Within each difficulty, later boards ask for more careful reasoning. Easy and Normal stay friendly even near the end, while Hard and above regularly need you to look at two or three regions together.
Daily challenge and weekly travel
The daily challenge gives everyone the same board for each date. It starts small at the beginning of the month (6x6 for the first week), grows to 7x7 in the second week and reaches 8x8 from the 15th. Finished days get a star on the calendar, and you can go back and play days you missed. Complete every day of a month to earn that month's trophy.
Every Monday your pets also set off on a trip to a new landmark, chosen from a list of 100 places. The photo of the landmark is split into 21 pieces, and each piece is a board of its own, marked with a colored dot for its difficulty. You can pick the pieces in any order. Finish all 21 and the destination's stamp goes into your passport.
Pets to collect
There are 100 pets in all. You pick a starter pet the first time you play, and every pet you place in a finished board counts toward the next unlock. When the gauge fills, you choose which locked pet joins you. Your collection is what appears on the boards, and you can choose which pet greets you on the main screen.
Hints
The Pet Hint button places one correct pet for you. On Hard, Expert and Master there is also Auto X: for ten minutes, every correct pet you place crosses out its row, its column, the squares around it and the rest of its region automatically. Auto X is left out on Easy and Normal on purpose, because on those small boards it would do almost all the work. New players start with three of each. In the apps you can get more by watching a short ad or from the hint shop. The browser version on this page has no ads or purchases, so it uses only the hints you start with.
Tips for new players
As soon as a pet lands, its row, its column, its region and the eight squares around it are closed. Marking them right away keeps the board readable.
A region of two or three squares has very few places left for its pet, and that usually decides a row or column too.
A wrong pet costs a heart and leaves a red X. If you are not sure, keep reasoning with X marks first.
Early-month dailies are small 6x6 boards, which makes them a good way to start a session before moving on to your main difficulty.
The guides below walk through real boards step by step, from the first easy patterns to two- and three-color locks on Hard.
Step by step
Guides for PetDoku
Each guide takes one real board from the game and solves it move by move, with a picture for every step.
Why players come back
Features
- 10,000 solver-verified stages across five difficulties (5x5 to 12x12)
- Pure logic — every stage is solvable by deduction, never by guessing
- Daily challenge calendar and 100 pets to collect
- Hints, auto-save and cloud sync — free in your browser, also on iOS, Android and Amazon
Common questions
Frequently asked questions
Is PetDoku free?
Yes. The browser version on this page is free with no ads. The iOS, Android and Amazon apps are also free to download, show ads at some points and offer optional purchases such as hint packs.
Will I ever have to guess?
No. Every board was checked by a solver so that it has one answer and can be reached step by step. If you feel stuck, there is a logical next move somewhere on the board.
Is it the same as the Queens puzzle?
The rules belong to the same family as the puzzle many people know as Queens, or a one-star Star Battle. PetDoku uses pets instead of crowns and adds hearts, hints, daily boards, travel and a pet collection.
Is my progress saved?
Yes. A board in progress is saved on your device, and your levels, pets and hints are kept on our server. In the browser your account is tied to that browser, so clearing site data starts a new one.
Which languages are supported?
PetDoku is available in 10 languages, including English, Korean and Japanese.
