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Sudoku Solver
Enter a Sudoku puzzle — type digits into the grid, paste an 81-character string (use 0 or . for blanks), or load a sample — and solve it instantly. The solver uses backtracking with a minimum-remaining-values heuristic and reports whether the puzzle has a unique solution. Everything runs locally in your browser.
The board is a standard 9×9 Sudoku. Type 1–9 in any cell; delete or 0 clears. Solve fills the blanks (blue) with the unique solution if one exists, and warns if a puzzle is invalid, has no solution, or has multiple solutions. The thicker lines mark the 3×3 boxes. Runs locally — your puzzle never leaves your browser.