Cat Sudoku tips and strategies
Quick answer: start with the smallest regions, cross out every cell around each new cat, and look for regions that fit inside a single row or column. On big boards, find groups of regions that share the same rows. These seven techniques solve every board on Puzzdoku without guessing.
1. Start with the smallest region
A region with one cell is a free cat. A region with two cells side by side gives you a strong clue: whichever cell gets the cat, the cells touching both of them can be crossed out.
2. Cross out around every cat
Every cat rules out its whole row, its whole column, its whole region and the eight cells touching it. Do this right away (or switch on Auto ✕) so the board stays readable.
3. Last cell standing
When a row, column or region has only one open cell left, its cat goes there. This is the move that finishes most easy boards, and the one the in-game hint calls "only one cell is left".
4. A region locked into one line
If every open cell of a region sits in the same row, that region's cat will use up the row. Cross out the rest of the row. It works the other way too: if a row's open cells all belong to one region, the rest of that region is empty.
5. Touch eliminations
Imagine a cat in a cell. If that cat would cross out every remaining cell of some region (or row, or column), it can't go there, because that region would be left without a cat. Small regions next to a cell are the usual giveaway.
6. Region groups
If two regions fit entirely inside the same two rows, those two regions will put their cats in exactly those rows. No other region can use them, so cross out every other cell in both rows. The same logic works for three regions in three rows, and for columns. This is the key technique for hard 8×8 and 9×9 boards from level 29 on.
7. Count what's left
Near the end, compare the rows, columns and regions that still need a cat. With three cats to go, you're solving a tiny 3×3 puzzle, and the touching rule often settles it in one move.
Practice plan
| If you're… | Play | Focus on |
|---|---|---|
| Brand new | Levels 1–8 | Tips 1–3 |
| Comfortable | Levels 16–28 | Tips 4–5 |
| Looking for a challenge | Levels 40–50 | Tips 6–7 |
| Building a habit | Daily Cat Sudoku | Keep your streak alive |
Frequently asked questions
What's the best first move in Cat Sudoku?
Find the smallest region. A one-cell region is a free cat, and a two- or three-cell region that sits in a single row or column instantly tells you which row or column that cat uses.
How do I solve hard Cat Sudoku boards?
On 8×8 and 9×9 boards, look for groups: if two regions fit entirely inside the same two rows, those two rows are 'used up', so every other cell in those rows can be crossed out. The same works with three regions in three rows, and with columns.
Should I cross out cells or just place cats?
Cross out generously. Most of the solving in Cat Sudoku is elimination; cats appear once a row, column or region has only one cell left. Drag across the board to cross out many cells at once.
Is it okay to use hints?
Yes. The Hint button explains the next logical step in words and highlights the cells involved, so it teaches the technique rather than just giving the answer.