Free online Sudoku
Classic Sudoku 6x6
Classic Sudoku 6x6 is a focused grid for practicing row, column, and box logic without losing track of the board. Choose a difficulty, solve in the browser, and switch to another size when you want a different pace.
Current board
6x6 Sudoku for quick practice before moving to 8x8 or 9x9-style logic.
Play Classic Sudoku 6x6 online with 2x3 boxes, symbols 1-6, and a clear grid for focused logic practice.
Grid
6x6
Box
2x3
Symbols
1-6
6x6 SudokuMedium
Classic Sudoku keeps the familiar row, column, and box logic while changing the grid size for fast practice or longer challenges.
Classic Sudoku board
Medium · 6x6-medium-001
Entry deck
Keep digit entry, pencil marks, undo, redo, clear, and conflict scan beside the grid.
Focus a playable cell
Select a cell to begin.
Train every row, column, and box
Classic Sudoku 6x6 keeps the logic visible: each row, column, and 2x3 box uses 1-6 once, so every placement has a clear reason.
Every symbol has one place
The answer is not guessed. Scan missing symbols, compare the crossing units, and use pencil notes only when the board still has two or three real candidates.
Scale the practice without changing the rules
Use compact boards for warmups and larger boards for longer sessions. The same row, column, and box rule stays in place, while the solving pace changes.