Challenge your mind with our professional Sudoku puzzle game. Six difficulty levels, smart hints, note-taking mode, and mistake tracking — all in your browser, no sign-up needed.
Sudoku is more than just a numbers game — it's a workout for your brain. Regular practice improves concentration, logical reasoning, and short-term memory. Whether you play for five minutes or an hour, each solved puzzle gives your mind a satisfying challenge and a confidence boost. Best of all, no math skills are needed — just pure logic.
Sudoku is a logic-based number placement puzzle played on a grid. In the classic 9×9 version, the goal is to fill every row, column, and 3×3 box with the digits 1 through 9, with no repetition. Our 6×6 variant uses digits 1–6 in 2×3 boxes — perfect for beginners or a quick brain warm-up. Every puzzle has exactly one valid solution, discoverable through pure deductive reasoning.
Pick Easy for a relaxed session, or push yourself with Expert, Master, or Extreme. Higher difficulties remove more starting numbers.
Click any empty cell on the board to select it. Use arrow keys to navigate between cells without lifting your hands from the keyboard.
Press a digit key or tap a number in the pad below the board. The number appears in the cell and is instantly checked for conflicts.
Toggle Notes mode to pencil in candidate numbers without committing. Notes help you track possibilities across rows, columns, and boxes.
Use Undo to step back one move, or Erase to clear a cell. You have three mistake allowances before the game ends — choose carefully!
Before placing a number, scan every row and column in that box to eliminate possibilities. Often a single candidate will remain.
Look for cells where only one number can legally fit. These 'naked singles' are the easiest placements and unlock harder cells.
Activate Notes mode and fill in all possible candidates for empty cells. When a candidate appears only once in a row, column, or box, it must go there.
Focus on a box that's nearly complete. Adding one or two numbers to a dense box often cascades — unlocking neighbors in the same row and column.
If you're stuck, step away for a minute. A fresh pair of eyes often spots the move that was hiding in plain sight.
