Free Sudoku Online
A brand-new Sudoku every game, always with a unique solution. Pick your level, use pencil notes and ask for a hint when you get stuck.
How to play Sudoku
The grid has 9 rows, 9 columns and 9 boxes of 3×3. The goal is to fill every empty cell with a number from 1 to 9 without repeating any number in the same row, column or box.
Tap a cell and then a number on the keypad below the grid (on a computer, you can type 1 to 9, move with the arrow keys and erase with Backspace). When you select a cell, its row, column, box and matching numbers are highlighted to make the grid easier to read.
Turn on “Notes” (or press N) to pencil in the candidates for each cell; when you place a number, it’s automatically removed from the notes around it. If you make a mistake, use “Undo”, keep “Show conflicts” on to see repeats in red and, if you’re really stuck, ask for a “Hint”.
Frequently asked questions
What’s the difference between the Sudoku levels?
Easy gives you more numbers and can be solved just by finding the only possible cell for each number. Medium and hard have fewer clues and call for techniques like pairs, triples and X-wing. Expert has the bare minimum of clues and takes more advanced reasoning.
Does every Sudoku here have a single solution?
Yes. Every puzzle is generated on the spot and checked by a solver before it shows up, so there’s always exactly one answer and you can get there with pure logic, no guessing.
How do notes work?
With notes on, numbers go into the cell in tiny print, like pencil marks. Use them to jot down possible candidates and cross them off as you go. On a computer keyboard, Shift + number also adds a note.