Welcome to the Coloured Sudoku puzzle.

Each square outlined in blue contains 9 small squares. Each of these small squares must be a different colour. Also, you can't have the same colour repeated in the same row or column of 9 squares.

To fill an empty square with a colour, first click on the colour from the Colour Selector, then click inside the small square in the puzzle you want to fill. The squares marked with a white cross can't be changed.

If you make a mistake, you can reset the colour to white by clicking in the white box, then in the square you want to reset.

Sounds complicated? You'll soon get the idea. If you want to re-start, then use the browser's 'refresh' button. Good luck. This one's really tricky.

See Solution

Colour Selector

Reset to white