Standard, small and large grids
Standard sudokus consist of a square grid 9 wide and 9 high using the numbers 123456789.

Small sudokus consist of a square grid 4 wide and 4 high using the numbers 1234.

Large sudokus consist of a square grid 16 wide and 16 high using the numbers and letters 123456789ABCDEF.

Easy, medium and hard
The difficulty of any sudoku depends on the number of values provided at the start, known as 'givens' - the fewer givens, the harder the sudoku is to solve. However, unlike crosswords, sudokus are entirely logical which means that they can be solved very easily by a computer.

Numbers and/or letters
A standard sudoku uses the numbers 123456789, though any combination of numbers, letters or symbols can be used.

Symmetric and non-symmetric grids
Symmetric grids are sudokus where the givens are arranged symmetrically.

Non-symmetric grids are sudokus where the givens are arranged randomly.

On-line interactive puzzles
Typically, puzzles are delivered as image files which can be imported into your desktop publishing software. We can also create online versions which can be incorporated into your website. These are Java applets, which means that they will work in most modern Internet browsers.

Fully managed competitions
We provide a fully managed competition service which can be tailored to your specific requirements, including a PO Box where solvers can send their entries. Contact us for further information.