Sudoku rules illustrated
A completed grid highlights a row, a column and a 3×3 box to show the three standard Sudoku constraints.
Naked pair Sudoku: before and after
A row-level diagram shows two cells containing only 3 and 7, followed by the candidate eliminations they allow.
How to read this diagram
When exactly two cells in a unit contain only the same two candidates, those digits are reserved for those cells.
Remove 3 and 7 from the other cells in this row. This is a candidate schematic, not a complete Sudoku grid.
Image prepared by Sudokumax. Updated .
More to explore
All Sudoku images
X-Wing Sudoku diagram
A candidate diagram shows the four corners of an X-Wing and the sevens it eliminates in the shared columns.
Killer Sudoku two-cell sum combinations
A complete reference chart of the nonrepeating digit pairs for two-cell Killer Sudoku cages, covering sums 3–17.