SudokuHard

Hard Sudoku — Puzzle 80

287
5684
31
746
162
75
4
173
57948

How to play

Fill every row, every column and every 3 by 3 box with the numbers 1 to 9, using each number once.

This puzzle has 26 given numbers and exactly one solution, so it can always be finished by reasoning alone.

238419675
917562834
465783219
752894361
196235487
843176592
374928156
589641723
621357948