PLAY SUDOKU
Gemini

๐Ÿ” Sudoku Solver with Steps

Samples:

Click cell & type 1โ€“9 (or use numpad). Backspace / Delete to clear.

Step Analysis Ready

Enter known numbers into the grid or load a sample puzzle, then click Next Step to analyze logical deductions cell by cell.

How the Step-by-Step Sudoku Solver Works

Unlike basic solvers that only spit out the final filled grid using brute-force algorithms, the NetSudoku Solver mimics human deductive logic. It analyzes candidate grids and discovers solving techniques in order of complexity:

  • Naked Singles: The cell has 8 conflicting numbers in its intersecting row, column, and box, leaving exactly one valid digit.
  • Hidden Singles: While the cell may have multiple open candidates, a specific number only has one legal location within that entire row, column, or 3ร—3 box.
  • Naked Pairs: Two cells in the same unit share the exact same two candidates, locking those digits into those cells and eliminating them from the rest of the unit.
  • X-Wings: A candidate appears in only two positions in two parallel rows/columns sharing the same perpendicular coordinates, eliminating it from other cells in those lines.