Help Read the help page on Sudoku puzzles for a more detailed explanation.
Pencil Marks What is a pencil mark? Pencil marks can help you keep track of your own thinking, simply enter more than one digit/letter into each square, just like you might do if you were using pen and paper. The size of the digits/letters is smaller when there is more than one digit/letter in a square. A square might contain more pencil mark digits/letters than can be shown.
Keyboard Usage[only when your cursor is in the grid] Note: only when supported by your computer/device/browser/etc. Ctrl + Arrows = move around the grid. a = auto-pencil marks. p = show a pinned square. Shift + # = show squares with a <#>.
Uniqueness Each puzzle has exactly one solution, which can be found using logic alone and no guesses are ever required. If you think you've found another solution, then please double check the rules.
Printing Only BrainBashers Sudoku can be printed (the starting grid, without pencil marks).
