How to play
Fill the grid so that every row, every column and each of the nine boxes holds every digit from 1 to 9 exactly once. The bright white digits are given and stay put; yours are copper.
Pick a cell and tap a digit. If the same digit already stands in its row, column or box, the cell turns coloured. The game does not tell you whether an entry matches the solution; the puzzle is solved once everything is right.
Controls
- Notes: switch them on and tap the digits that could fit a cell.
- With the keyboard you move with the arrow keys, type digits directly, delete with Backspace and toggle notes with N.
- Undo takes back every entry, notes included.
Frequently asked questions
- Is this Sudoku free?
- Yes. No ads, no purchases, no account. Every puzzle is new and there are endless more.
- Does every puzzle have exactly one solution?
- Yes. Each puzzle is checked when it is created: it can be filled in only one way. You never have to guess.
- What sets the three levels apart?
- The number of given digits: easy has 40, medium 32, hard 26 to 27. The fewer given, the longer you think.
- How do I take notes?
- Switch on “Notes” and tap digits. They appear small in the cell. When you place a digit, the same note disappears from its row, column and box by itself.
- Is my puzzle saved?
- Yes, after every entry, but only in your browser. Next time you continue the same puzzle.