SudokuHard

Hard Sudoku — Puzzle 249

21
86
3
691
467
5837
187
48521
129

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.

425379618
178246935
369518247
697152483
834697152
512834769
253961874
946785321
781423596