One certainty at a time.
About this game
How to play Sudoku
Fill each row, column and outlined three-by-three box with the digits 1 to 9, once each. The printed clues cannot be changed. Tap a square, then a digit, or use your keyboard. Arrow keys move your selection. Erase clears an editable square.
A puzzle with a little personality
Easy, Medium, Hard and Expert use progressively fewer clues. Every generated puzzle has exactly one solution. Difficulty describes clue density, not a human-solving-technique rating. Notes let you pencil in possibilities. Conflicting digits are marked; Hint offers a correct digit for an unfinished square.
Orrin’s advice
Look for a row, column or box with only one missing number. Pencil in candidates before guessing. Notes are local helpers and do not count as moves.
Today’s shared puzzle
The daily puzzle changes at midnight in America/New_York. Everyone receives the same daily puzzle. Daily Sudoku uses Easy difficulty; daily Potion Sort uses a level-eight shelf. Start a verified run below to post a time to the live daily leaderboard. Hints and undo are allowed. The server checks the completed move history and measures elapsed time.