🔢 Sudoku

The Rules

Fill every row, every column and every 3×3 box with the digits 1–9 — each digit appearing exactly once. Given (grey) cells are fixed. Blue cells are yours to fill.

Tips for Beginners

Start with rows, columns or boxes that already have many numbers filled in — they have fewer possibilities. Look for digits that appear 7 or 8 times in the board — their last placement is forced. Work through each digit 1–9 to find where it must go.