Sudoku Classic and the 9x9 grid rule set
Sudoku Classic turns a familiar number puzzle into a tidy Puzzle run on a 9x9 board. Your job is to place digits so every row, column, and 3x3 block ends up with the numbers 1 to 9 only once.
Fill the board without breaking any line
The challenge is all about reading the grid and spotting what can still fit in each empty cell. If you enjoy logic games like Classic Sudoku Puzzle or Sudoku, this one keeps the same core rule pressure while asking you to stay precise.
Use markings when the puzzle tightens up
When a board gets crowded, the marking system helps you track possible numbers before you commit. That extra layer matters on harder layouts, and the built-in magic wand gives you a way out when you are stuck.
Choose a daily challenge or a difficulty level
You can jump into a daily challenge or pick from different difficulty settings, so the pace fits the board in front of you. Similar number-grid options such as Ultimate Sudoku HTML5 and Eleven Eleven show how much mileage this kind of logic play can have, and Sudoku keeps the focus on pattern reading and clean fills. It also works well as an Educational pick when you want a brain exercise that stays all about the rules.
Because the clue layout changes with each board, you end up checking numbers from more than one angle before placing a value. That makes it easy to settle in for a no download and no signup round whenever you want to clear a grid.