Do knights wrap around the edges?

No. A knight move only counts when both cells are on the grid.

Why are there fewer clues?

The extra rule removes a lot of candidates, so a puzzle needs fewer starting digits to have one answer.

Yes. Use 1 to 9 to place, arrow keys to move, N for notes and Backspace to erase.

Sudoku where cells a chess knight's move apart can never hold the same digit. A twist that cuts the number of clues needed.

Knight Sudoku

0% · Getting ready

A real run of the game, recorded with captions and no sound.

Fill the grid so every row, column and 3 by 3 box has each digit from 1 to 9 once.
Two cells a knight's move apart (two across and one down, or one across and two down) must hold different digits.
Tap a cell, then a number. Selecting a cell shades its row, column and box. Conflicts, including knight moves, turn red.
Every puzzle has one solution. There are fewer given numbers than in a normal Sudoku because the knight rule gives so much information.

Controls: mouse, touch or keyboard. Made by CalcoTools.

After placing a digit, look at the up to eight cells a knight can reach from it. None of them can be the same digit.
A digit that is already placed in the centre box rules out many cells around it.
Notes are worth the time here. The knight rule removes a candidate from cells far from the placed digit.
When two cells in the same group can only be one of two digits, check whether a knight's move links them to a third cell.

Do knights wrap around the edges?: No. A knight move only counts when both cells are on the grid.
Why are there fewer clues?: The extra rule removes a lot of candidates, so a puzzle needs fewer starting digits to have one answer.
Can I use it with the keyboard?: Yes. Use 1 to 9 to place, arrow keys to move, N for notes and Backspace to erase.