Today Sudoku contains very many types of variant Sudoku, more types of Sudoku puzzles are still under continuous development, please continue to pay attention to Sudoku today.

- Place a digit from 1 to 9 into each of the empty squares so that each digit appears exactly once in each of the rows, columns and the nine outlined 3x3 regions.
- If absolute difference between two digits in neighbouring cells equals 1, then they are separated by a white dot. If the digit is a half of digit in the neighbouring cell, then they are separated by black dot. The dot between 1 and 2 can be either white or black.

- Place a digit from 1 to 9 into each of the empty squares so that each digit appears exactly once in each of the rows, columns and the nine outlined 3x3 regions.
- If absolute difference between two digits in neighbouring cells equals 1, then they are separated by a white dot. If the digit is a half of digit in the neighbouring cell, then they are separated by black dot. The dot between 1 and 2 can be either white or black.

- Place a digit from 1 to 9 into each of the empty squares so that each digit appears exactly once in each of the rows, columns and the nine outlined 3x3 regions.
- The same numbers are not chess-knight move connected.

- The same numbers are not chess-knight move connected.

- Sujiken (from Japanese "sujikai", literally "diagonal") is a variation of Sudoku . The puzzle consists of a triangular grid of cells containing digits from 1 to 9. The objective is to fill a grid with digits so that each cell contains a digit and no digit is repeated in any column, row and diagonal in any direction. Also, no digit occurs twice in any of the three larger 3 x 3 square regions and any of the three larger triangular regions enclosed by thick borders.

- Sujiken (from Japanese "sujikai", literally "diagonal") is a variation of Sudoku . The puzzle consists of a triangular grid of cells containing digits from 1 to 9. The objective is to fill a grid with digits so that each cell contains a digit and no digit is repeated in any column, row and diagonal in any direction. Also, no digit occurs twice in any of the three larger 3 x 3 square regions and any of the three larger triangular regions enclosed by thick borders.

- Arrows and numbers outside gridding means how many different numbers in corresponding direction grid.

- Arrows and numbers outside gridding means how many different numbers in corresponding direction grid.

- An arrow in a cell indicates that the number in this cell is repeated at least once in the direction the arrow points to.

- An arrow in a cell indicates that the number in this cell is repeated at least once in the direction the arrow points to.

- The four corner boxes contain the same digit in symmetric positions about the centre.

- The four corner boxes contain the same digit in symmetric positions about the centre.

- If a shaded cell and a white cell are adjacent then the digit in the shaded cell is greater.

- If a shaded cell and a white cell are adjacent then the digit in the shaded cell is greater.

- A number at the edge of the diagram indicates the difference between the highest and the lowest number in the first three cells in the corresponding row or column.

- A number at the edge of the diagram indicates the difference between the highest and the lowest number in the first three cells in the corresponding row or column.

- If digit ‘n’ is placed in a cell with an arrow, digit ‘n+1’ must be placed in one of the cells pointed by the arrow.

- If digit ‘n’ is placed in a cell with an arrow, digit ‘n+1’ must be placed in one of the cells pointed by the arrow.

- A number at the edge of the diagram indicates the difference between the highest and the lowest number in the first three cells in the corresponding row or column.

- Digits along each line read the same from both directions.

- Digits along each line read the same from both directions.

- Numbers in the red circle are not allowed appears in four squares which is nearby the intersection of row and column red circles.

- Numbers in the red circle are not allowed appears in four squares which is nearby the intersection of row and column red circles.

- The connected shaded cells contain each digit from 1 to 9.

- The connected shaded cells contain each digit from 1 to 9.

- Each number at the intersection of four cells is the sum of digits in those four cells.

- Each number at the intersection of four cells is the sum of digits in those four cells.

- A number between two cells indicates the product of the numbers in these cells. A number between four cells indicates the product between two diagonally adjacent cells, either top left + right bottom (\) or top right + bottom left (/).

- A number between two cells indicates the product of the numbers in these cells. A number between four cells indicates the product between two diagonally adjacent cells, either top left + right bottom (\) or top right + bottom left (/).

- A number in a squared cell indicates how many different numbers the four diagonally adjacent cells contain. A number in a circled cell indicates how many different numbers the eight orthogonally and diagonally adjacent cells contain.

- A number in a squared cell indicates how many different numbers the four diagonally adjacent cells contain. A number in a circled cell indicates how many different numbers the eight orthogonally and diagonally adjacent cells contain.

- Digits have to be place in accordance with the “greater than” signs.

- Digits have to be place in accordance with the “greater than” signs.

- Cells with circles must contain digits 1-2-3, cells with squares must contain digits 4-5-6, blank cells must contains digits 7-8-9.

- Cells with circles must contain digits 1-2-3, cells with squares must contain digits 4-5-6, blank cells must contains digits 7-8-9.