SudokuHard

Hard Sudoku — Puzzle 169

6125
74
4137
5137
28
432
725
1
549

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.

618739245
357142689
492865137
245691378
973528416
186473952
721386594
839254761
564917823