Mini Sudoku is the classic number puzzle on a 6×6 board. Fill every empty cell with a number from 1 to 6.
The rules
Each row and each column needs the numbers 1 to 6 exactly once. So does each of the six outlined boxes, which are three cells wide and two cells tall. The numbers you start with are fixed.
Look for the missing number
Start with a row, column or box that’s nearly full. If it has one empty cell, you know what goes there. With two empty cells, work out the two missing numbers, then use each cell’s column and box to decide which goes where.
Worked example
Two missing numbers, one possible fit
- Row 1 has 2, 3, 4 and 6, so its two empty cells need 1 and 5.
- Column 5 already has a 1, so row 1, column 5 must be the 5. That leaves the 1 for the first cell in the row.
A teaching board, not one of today’s puzzles.
Where can this number go?
Pick a number that a box still needs and look at the box’s empty cells. Cross off any cell whose row or column already has that number. If only one cell is left, the number goes there. Sudoku players call this a hidden single, and it works for rows and columns too.
You can also come at it from the other side. Take one empty cell and rule out every number already in its row, column and box. If five of the six are gone, the last one goes in.
After each placement, look again at the row, column and box you just changed. One number often unlocks the next.
Entering numbers
Select an empty cell, then choose 1–6 on the number pad below the board. The pad stays on screen on phones and larger screens alike. With a keyboard, use the arrow keys to move and type 1–6. Erase, Backspace or Delete clears an entry. Starting numbers can’t be changed.
When something doesn’t fit
A number that appears twice in a row, column or box is a conflict. A number can fit its row and still clash in its column, so check all three. Use Undo to step back, or ask for a hint to find a placement to make or one to rethink.
For a gentle first board, choose Learn to play in the Mini Sudoku Library. When you’re ready for more, follow a complete Mini Sudoku solve.