GridWits
Medium tier Technique 5 of 46 Used by Smart Hint

Naked Pair

Two cells in a unit share the exact same two candidates — those digits can be removed from every other cell in the unit.

How it works

  1. 1A3 and E3 hold exactly the same two candidates, {1, 4}, and they sit in different boxes — only row 3 links them.
  2. 2Row 3 still has five empty cells, so nothing simpler applies: no cell is down to one candidate and no missing digit has just one home.
  3. 3Between them A3 and E3 must take both 1 and 4, so those digits leave every other cell in the row — C3 drops to {8, 9}.

Play a Sudoku that needs this technique →

A 1 B 2 C 3 D 4 E 5 F 6 G 7 H 8 I 9 1 4 7 1 4 8 9 2 8 1 4 3 2 9 5 6 1 4 1 4 1 4
  • Cells that establish the pattern
  • Where the conclusion lands
  • Candidate ruled out
Next in the ladder Naked Triple →

Three cells in a unit whose candidates combine to exactly three digits — eliminate those digits from the rest of the unit.