SudokuHard

Hard Sudoku — Puzzle 100

527
485
761
2831
391
38
1976
98
54

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.

528471369
461839752
397526814
286354197
739168425
154792638
815243976
642917583
973685241