Sudoku is a logic game that became popular in Japan in 1986 and internationally in 2005 when many newspapers began to publish in your puzzles section. The goal of sudoku is to fill a grid of 9 × 9 cells (81 boxes) divided in subgrids 3 × 3 (also called "boxes" or "regions") with the numbers 1 to 9 based on some numbers and arranged in some of the cells. Although you could use other symbols, like letters or figures, we use numbers for clarity. What matters is that there are nine distinct elements, which should not be repeated in the same row, column or subgrid. A sudoku puzzle is well formed if the solution is unique.
Press "New Game" to start a puzzle. Click or tap a box to place in a number. If you want to place the number "6" you need to click six times.