Smart SudokuPlay Sudoku online
Numbers, notes and the next logical move.
Opening your puzzle…
How to play
Fill each row, column and box with the numbers 1–6 or 1–9 exactly once. Fixed clues stay in place. Use pencil notes to track candidates, and ask for an explained logical step when you need a nudge.
A selection of starter puzzles with local progress on this browser. The iOS apps have their own features and purchase plans.
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Your solving tools
Switch between regular digits, independent corner and centre notes, and cell colours. Auto Pencil preserves valid eliminations; automatic note removal and matching-note cell highlights can be changed in Game settings.
Three free hints are available daily in this browser. Extra hints and AI Coach sessions require rewarded ads. Website rewarded ads are not available yet, so those rewards cannot currently be redeemed.