🧩 How to play 6x6 Sudoku

By Miguel Arechaga

6x6 sudoku is the perfect stepping stone between the simple 4x4 and the classic 9x9. It offers more of a challenge than the kids' version while staying accessible and quick to solve. Its distinctive feature is its rectangular 2x3 boxes. Here are the rules and how to solve it.

What is 6x6 sudoku?

It's a sudoku variant played on a 6x6 grid, divided into six rectangular 2x3 boxes (2 rows by 3 columns). The numbers 1 to 6 are used.

Rules and how to play step by step

1. Fill the grid with the numbers 1 to 6.
2. Each row must contain all six numbers without repeats.
3. Each column must contain all six numbers without repeats.
4. Each 2x3 box must contain the numbers 1 to 6, one of each.
5. Tap an empty square and choose the correct number.

Tips to solve 6x6 sudoku

• Pay attention to the rectangular boxes: being 2x3, they share information with two rows and three columns at once.
• Start with the numbers that already appear several times on the board.
• Use notes mode mentally: jot down the possible candidates for each uncertain square.
• Work by elimination: if a number can only go in one square of a box, place it.

Differences from the 4x4 and the 9x9

Compared to 4x4 sudoku, the 6x6 adds difficulty with its rectangular boxes and six numbers. Compared to the classic 9x9, it's still faster and less overwhelming, ideal for practicing sudoku techniques before jumping to the big board.

The 2x3 box strategy, properly explained

The detail that throws people off in 6x6 is that its boxes are rectangular (2 rows x 3 columns), not square. That changes the geometry of eliminations: each box crosses only 2 rows and 3 columns, so scanning by rows is more powerful than by columns. Recommended strategy: always start with the rows, which only have 6 cells and empty out fast; use the boxes to confirm; leave columns as the final check.

Another useful consequence: when a number already appears in two of the three boxes of a horizontal band, the remaining box has only 2 possible cells for it (one per row). It's the miniature equivalent of the 9x9's "pointing candidates" — visible here with the naked eye, no notes needed.

What 6x6 does for your progression

The 6x6 is the best gym for automating the hidden single: the board is small enough to spot it without pencil marks, and that reflex is exactly what later makes the difference in easy and medium 9x9. Two or three 6x6 boards a day for a week and you'll notice the 9x9 "reads" faster. When that happens, you're ready for the big board.

Frequently asked questions

How long does a 6x6 sudoku take?

Between 3 and 8 minutes depending on practice. It's the perfect format for a short break: more substance than a 4x4, without the time commitment of a 9x9.

Does 6x6 use the same techniques as 9x9?

The basics, yes: scanning, naked singles and hidden singles. Advanced ones (pairs, X-Wing) are almost never needed — the board is solved before they come up.

Is it suitable for kids?

Yes, from around 7-8 years old it's the ideal step after the 4x4. For younger children, start with 4x4 and our sudoku for kids guide.