All Sudoku Variants
6×6 · Size Variant

Sudoku 6×6

Also known as Mini Sudoku, Rokudoku

A 6×6 grid with 2×3 boxes and digits 1–6 — a common stepping stone between 4×4 and the full 9×9.

1 2 3 4 5 6

An example 6×6 Sudoku: digits 1–6 fill every row, column and 2×3 box.

6×6 Sudoku shrinks the classic grid to six rows and six columns, using the digits 1–6. The boxes become 2×3 rectangles instead of 3×3 squares, and each still has to hold every digit once — as do the rows and columns. Smaller, faster and far gentler than the full 9×9, it is the perfect grid for children and newcomers, and a quick warm-up for everyone else.

The rule: 1–6 in every row, column and 2×3 box

Fill the grid so that each row, each column and each 2×3 box contains the digits 1 to 6 exactly once. The rectangular boxes are the only real difference from Classic Sudoku — two cells tall and three wide — so a "box" no longer lines up with a neat square. Here is a completed 6×6 grid.

1 2 3 4 5 6 4 5 6 1 2 3 2 3 4 5 6 1 5 6 1 2 3 4 3 4 5 6 1 2 6 1 2 3 4 5

A finished 6×6 grid: every row, column and 2×3 box holds 1–6 once.

Rectangular boxes change the feel

Because a 2×3 box spans three columns but only two rows, it interacts with rows and columns differently from a square box. A digit placed in a box removes it from three columns' worth of that box but only two rows' worth — so column scanning tends to be more powerful than row scanning in a 6×6, a small asymmetry that is worth noticing. Some 6×6 puzzles instead use 3×2 boxes (three tall, two wide); the logic is the same, just rotated.

A gentle place to learn

With only 36 cells and six digits, a 6×6 is quick to finish and hard to get lost in, which makes it ideal for teaching the core habits of Sudoku: scanning a unit for a missing digit, spotting a cell with only one option, and pencilling candidates. Every technique that works on a 9×9 works here in miniature — hidden singles and naked pairs appear just as they do on the big grid, only sooner.

Solving strategy

  • Scan columns first. The wide 2×3 boxes make column eliminations especially effective.
  • Hunt hidden singles. With six cells per box, a digit is often confined to a single empty cell quickly.
  • Pencil the pairs. Naked and hidden pairs still apply and resolve fast on the small grid.
  • Use it to teach. The 6×6 is the best size for building scanning skills before moving up to 9×9.

Common mistakes

  • Expecting square boxes. The boxes are 2×3 rectangles — check the printed borders before reasoning about a box.
  • Using digits above 6. Only 1–6 appear; there is no 7, 8 or 9.
  • Forgetting a rule. Rows, columns and boxes all still apply, exactly as on the full grid.
  • Underrating it. A hard 6×6 can still require real deduction — small does not always mean trivial.

Can I play it here?

Not yet — Sudoku 6×6 isn't one of the puzzle types SudokuStreak generates for now. But you can learn its rules above, and there's plenty here to sink your teeth into meanwhile: