- 4×4 Sudoku uses digits 1–4 with 2×2 boxes — solvable in 30 seconds once understood
- 6×6 Sudoku uses digits 1–6 with 2×3 or 3×2 boxes — a perfect bridge to 9×9
- The rule is identical: each symbol appears once per row, column, and box
- Mini grids are excellent for teaching children, beginners, and classroom use
- Techniques (scanning, singles) transfer directly to 9×9 — mini grids build the right habits
4×4 Sudoku
A 4×4 Sudoku has 16 cells arranged in 4 rows, 4 columns, and four 2×2 boxes. The symbols are typically 1, 2, 3, and 4. Each row, column, and box must contain all four symbols exactly once.
A 4×4 puzzle typically starts with 4–8 given digits and is solvable in under a minute. It is ideal for children aged 5–8 or adults who have never played Sudoku and want to understand the core rule before tackling a 9×9.
6×6 Sudoku
A 6×6 Sudoku has 36 cells in 6 rows, 6 columns, and six boxes. The boxes are either 2×3 (two rows, three columns) or 3×2, depending on the puzzle design. Symbols are typically 1–6.
A 6×6 puzzle is significantly more complex than a 4×4 but still manageable in 3–8 minutes for a beginner. It introduces the same techniques — scanning, Naked Singles, Hidden Singles — that are essential in 9×9, making it the ideal stepping stone.
Comparison Table
| Grid | Cells | Symbols | Box Shape | Units |
|---|---|---|---|---|
| 4×4 | 16 | 1–4 | 2×2 | 12 |
| 6×6 | 36 | 1–6 | 2×3 | 18 |
| 9×9 | 81 | 1–9 | 3×3 | 27 |
| 16×16 | 256 | 1–9, A–G | 4×4 | 48 |
Teaching with Mini Sudoku
Mini grids are perfect for introducing Sudoku to children because the rule is visible in just a few seconds. With only 4 symbols and 16 cells, a child can check every constraint by eye without pencil marks. Once they understand the rule on a 4×4, a 9×9 grid simply extends the same idea to more cells and more symbols.
For classroom use, printable 4×4 and 6×6 puzzles are available on most Sudoku sites. Once comfortable with mini grids, guide learners to Easy 9×9 puzzles as the next step. Our full how to play guide covers both mini and standard grid techniques.