What is a 6×6 sudoku?
A 6×6 sudoku is exactly what it sounds like — a sudoku grid that’s six squares wide and six squares tall, with thirty-six little squares in total. Instead of the numbers 1 to 9, you only use the numbers 1, 2, 3, 4, 5 and 6. Some squares already have numbers in them when you start, and your job is to fill in the rest.
The grid is split into six little boxes by slightly thicker lines. Each box is two squares tall and three squares wide (a 2×3 rectangle), not a square — that’s the only big difference from the bigger sudoku you’ve probably seen on TV.
6×6 is the perfect middle step. If you’ve already mastered our 4×4 sudoku grid, this is the natural next adventure. And once 6×6 feels easy, the full 9×9 sudoku game is just a small jump away.
The three rules — same as always
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Every row uses 1 to 6
A row is a line going across. Each of the six rows must have all six numbers (1, 2, 3, 4, 5 and 6), with no repeats.
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Every column uses 1 to 6
A column is a line going down. Same rule — every number from 1 to 6 must appear once. The numbers don’t have to be in order, just present.
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Every 2×3 box uses 1 to 6
See the thicker lines? They split the grid into six little 2×3 boxes (two rows tall, three columns wide). Each box also needs the numbers 1 to 6, with no repeats.
How is 6×6 different from 4×4 and 9×9?
A 4×4 sudoku has only 16 squares and uses 1 to 4. It’s lovely for very young kids but most children outgrow it quickly — sometimes in just a week or two. A 9×9 sudoku has 81 squares and uses 1 to 9. It’s the "real" sudoku you see in newspapers, but it can feel huge and overwhelming for a kid who’s only ever played 4×4.
6×6 sits in the middle. It has 36 squares — more than twice as many as 4×4, but still less than half a 9×9. Most kids can finish a 6×6 puzzle in five to ten minutes once they know the rules.
The other interesting difference is the box shape. In 4×4 the boxes are little 2×2 squares. In 9×9 they’re neat 3×3 squares. In 6×6 they’re 2×3 rectangles, which can feel a bit unusual at first. Don’t worry — your eyes get used to it after one or two puzzles.
Three strategies that work in 6×6
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Find the "missing one"
Any row, column or box with five numbers already in it has only one missing. Those are the easiest squares — fill them in first to give yourself a head start.
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Hunt one number at a time
Pick a number, like 4. Look at each of the six rows in turn. If a row is missing a 4, see which empty squares it could go in (check the columns and boxes too). Only one option? Fill it in. Then move on to the next row, then the next number.
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Use the boxes as your friend
Each 2×3 box must use 1 to 6. If a box already has 1, 2, 3 and 4, you only need to find homes for 5 and 6 — a tiny puzzle inside the puzzle.
How to play on Sudoku for Kids
Tap any empty square. It gets a yellow highlight, and the squares that share a row, column or box with it light up softly so you can see what’s already used. Then tap a number from 1 to 6 on the pad below the board.
If you make a mistake, the wrong number shows in red. Tap the square, then tap Erase (🧽) to clear it, and try again. There’s no penalty and no buzzer — the mistakes counter is just for fun.
If you get stuck, tap an empty square and then tap Hint (💡). The right number appears. Try not to use it on every puzzle — but it’s a friendly safety net.
Why 6×6 is the perfect next step
- ⏱️ Long enough to feel like a real puzzle, short enough not to drag.
- 🔢 Practises the numbers 1–6 — the next natural step after 1–4.
- 🧠 Introduces "scanning" — looking at a whole row or column at once.
- 👀 Teaches your eyes to recognise rectangle-shaped boxes, ready for 9×9.
- ✨ Gives the same satisfying "I did it!" feeling as a full sudoku.
The big win of 6×6 is that it teaches the same techniques that work in 9×9 — scanning, missing-number, candidate notes — but in a smaller, less scary playground. Kids who go straight from 4×4 to 9×9 sometimes feel overwhelmed; kids who play a few weeks of 6×6 in between often glide right into the bigger grid.
Ready for the full game?
When you can finish a 6×6 puzzle in five minutes or less, you’re ready to try the Easy 9×9 sudoku. Don’t worry that the grid looks bigger — the rules are exactly the same. You’ll just be using all nine numbers instead of just six, and the boxes are 3×3 squares.
Want to try something completely different? Have a look at our Killer Sudoku game. It’s a 9×9 sudoku with extra "cage" sums to add up — the friendliest way to mix sudoku with a tiny bit of mental maths.
Frequently asked questions
What age is 6×6 sudoku good for?
Most kids enjoy 6×6 sudoku from age 6 or 7, especially if they’ve already played a few 4×4 puzzles. The numbers 1–6 are familiar and the grid is still small enough not to feel overwhelming.
How long does a 6×6 sudoku take?
Five to ten minutes for a new player. Once a child knows the strategies, they often finish in two or three minutes.
How is 6×6 different from 4×4?
It has more than twice as many squares (36 vs 16) and uses two extra numbers (1–6 instead of 1–4). The boxes are also 2×3 rectangles instead of 2×2 squares.
How is 6×6 different from full 9×9 sudoku?
Same rules, but smaller. 9×9 has 81 squares, uses 1–9, and the boxes are 3×3 squares. 6×6 is a friendly stepping stone — the same techniques work in both.
How do I know my child is ready for 9×9?
A good sign: they finish most 6×6 puzzles in under five minutes without needing a hint. At that point, Easy 9×9 will feel like a fun challenge instead of a wall.
Do I need an account?
No. No signup, no ads, and your puzzle progress is saved in the browser, so you can come back later.
Can I play 6×6 offline?
Yes. Once the page has loaded, the game works without an internet connection — perfect for car trips and aeroplanes.
Where next?
Once these feel easy, step up to a bigger grid.