Box Brain Sudoku
Rules › Sandwich
How to play Sandwich sudoku
Sandwich sudoku puts numbers outside the grid. Each one is the sum of the digits sandwiched between the 1 and the 9 in its row or column.
What lies between 1 and 9.
The rules
- Classic rules apply: every row, column and 3×3 box holds the digits 1 to 9 once each.
- A number outside the grid is the sum of the digits between the 1 and the 9 in that row or column.
Where to start
- A sum of 0 means the 1 and the 9 sit side by side. A sum of 35 means they sit at the two ends.
- A sum of 2, 3 or 4 means exactly one digit sits between the 1 and the 9.
- The digits between are always from 2 to 8, so a sandwich can never hold a 1 or a 9 of its own.
Play Sandwich in Box Brain Sudoku
Every Sandwich puzzle in the app has exactly one solution and can be solved by logic alone, from Easy to Expert. Stuck? A hint first nudges you towards the right area, then names the technique and shows the move.