Number 4 is the only value possible in cell (1,4).

Number 6 is the only value possible in cell (1,3).

Number 5 is the only value possible in cell (1,5).

Number 6 is the only value possible in cell (2,6).

Number 5 is the only value possible in cell (7,6).

Number 4 is the only value possible in cell (9,6).

Number 1 is the only value possible in cell (1,9).

Number 2 is the only value possible in cell (1,8).

For row 5, number 3 is only possible in cell (2,5)

For row 7, number 3 is only possible in cell (4,7)

For row 2, number 5 is only possible in cell (9,2)

For row 2, number 2 is only possible in cell (4,2)

For row 2, number 6 is only possible in cell (6,2)

Number 7 is the only value possible in cell (6,9).

Number 5 is the only value possible in cell (2,9).

For row 1, number 2 is only possible in cell (2,1)

For row 5, number 2 is only possible in cell (8,5)

For row 5, number 9 is only possible in cell (7,5)

For box 8, candidates for 4 are all in row 8, so you can remove candidates from other blocks.

For box 4, candidates for 7 are all in column 3, so you can remove candidates from other blocks.

Naked Pair for 1 and 8, can remove these as candidates from other cells.

Naked Pair for 3 and 9, can remove these as candidates from other cells.

For box 8, candidates for 9 are all in column 5, so you can remove candidates from other blocks.

Naked Pair for 1 and 7, can remove these as candidates from other cells.

Naked Pair for 7 and 8, can remove these as candidates from other cells.

For box 3, candidates for 7 are all in column 7, so you can remove candidates from other blocks.

For row 8, number 7 is only possible in cell (2,8)

X-Wing in columns for 8.

Either candidate for cell (9,1) forces 9 into cell (5,7).

Number 4 is the only value possible in cell (2,7).

Number 9 is the only value possible in cell (2,3).

Number 4 is the only value possible in cell (3,2).

Number 9 is the only value possible in cell (8,2).

Number 3 is the only value possible in cell (8,1).

Number 9 is the only value possible in cell (6,1).

Number 3 is the only value possible in cell (6,3).

Number 4 is the only value possible in cell (8,3).

Number 6 is the only value possible in cell (3,7).

Number 7 is the only value possible in cell (8,7).

Number 8 is the only value possible in cell (8,4).

Number 7 is the only value possible in cell (3,4).

Number 8 is the only value possible in cell (3,5).

Number 7 is the only value possible in cell (9,5).

Number 1 is the only value possible in cell (9,7).

Number 8 is the only value possible in cell (9,1).

Number 1 is the only value possible in cell (4,1).

Number 7 is the only value possible in cell (5,2).

Number 1 is the only value possible in cell (7,2).

Number 8 is the only value possible in cell (5,3).

Number 7 is the only value possible in cell (7,3).

Number 4 is the only value possible in cell (4,5).

Number 1 is the only value possible in cell (6,5).

Number 9 is the only value possible in cell (3,8).

Number 6 is the only value possible in cell (4,8).

Number 1 is the only value possible in cell (5,8).

Number 4 is the only value possible in cell (6,8).

Number 8 is the only value possible in cell (7,8).

Number 8 is the only value possible in cell (4,9).

Number 6 is the only value possible in cell (8,9).