How to Play Color Sudoku

The Basics

Color Sudoku follows the exact same rules as classic Sudoku, but replaces the numbers 1–9 with 9 distinct colors. If you know Sudoku, you already know Color Sudoku.

The board is a 9×9 grid divided into nine 3×3 boxes. Some cells are pre-filled with colors (the "givens"). Your job is to fill in the rest.

Rules

1. Every row must contain all 9 colors — no repeats.
2. Every column must contain all 9 colors — no repeats.
3. Every 3×3 box must contain all 9 colors — no repeats.

Controls

• Click a cell, then click a color to place it.
• Keyboard: Arrow keys to navigate, 1–9 to place colors.
• Notes mode (N): Toggle to pencil in candidate colors.
• Undo/Redo: Ctrl+Z / Ctrl+Y (or Cmd on Mac).
• Hint (H): Reveals one cell using logical deduction.
• Erase (Backspace): Clear the selected cell.

Tips

• Look for rows, columns, or boxes where 8 of 9 colors are placed — the last color is forced.
• Use notes mode to track which colors are possible in each cell.
• The color legend below the board shows which number each color represents.
• Enable "Show Numbers" in settings if you want numbers overlaid on colors.

Daily Puzzle

A new puzzle is generated every day, seeded by the date. Everyone gets the same puzzle — compare times with friends by sharing your results!