Mini sudoku is classic sudoku shrunk to four rows and four columns. Tap a blank cell, then tap a number. Wrong numbers turn red so you can fix them quickly, and every puzzle has exactly one solution.
Start with any row, column or box that is nearly full. If three cells are filled, the fourth is forced. Then use the numbers you have added to fill neighbouring lines.
Four-by-four sudoku is a gentle way to learn the logic of the full 9×9 game, because you can see every possibility at once. Once these feel easy, you are ready for larger grids.
Frequently asked questions
What are the rules?
Each row, column and 2×2 box must contain the numbers 1 to 4 exactly once.
Does every puzzle have a unique solution?
Yes. Each is checked so only one solution exists.
Does it show mistakes?
Yes. A number that does not match the solution turns red.