Sudoku Classic

★ 4.7 | 203K plays | Puzzle Games

The timeless number puzzle, beautifully designed for your browser. Four difficulty levels from Easy to Expert. Includes pencil marks and undo.

How to Play

Controls: Click a cell, then click a number (or type 1-9) to fill it. Right-click to toggle pencil marks.

Goal: Fill the 9x9 grid so every row, column, and 3x3 box contains digits 1-9 exactly once.

Pro Tips

Use pencil marks to note candidates. A clean notation system saves you from guesswork.
Scan rows, columns, and boxes for cells with only one possible number — those are freebies.
Start on Easy to learn the patterns. The same logic scales up — only the depth changes.