Our irregular hexadoku puzzles are 16 X 16 fiendish sudoku. Instead of nine 3 X 3 square areas, you have 16 areas of irregular shapes each with 16 squares. The rules are the same as for a classic sudoku. You need to find by deduction 16 different digits by row, column and area.

To reduce the size of the grid on the screen and to facilitate entering values, the possibilities are represented here by the following hexadecimal digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E and F.
The hexadecimal system is a numeral system with a base of 16, using Arabic numerals to represent values 0-9 and the letters A-F for the other six. The hexadecimal is especially useful in computer science because it is much easier to map binary to hexadecimal than to decimal.

You have 60,000 puzzles presented in two forms and three levels.
Forms: Symmetrical or asymmetrical.
Levels: beginner, confirmed, expert.

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Download with PDF format

If the borders and/or the colors of the grid are not printed, check if the "Print images" option of your browser is not switched off.
In this case you can download our grids as PDF files and then print them. You will get a faithful presentation of our special samurai sudoku grids.

Our irregular jigsaw hexadoku are downloadable through the menu 16X16 JIGSAW SUDOKU and the link Download pdf puzzles.
You can select pdf in white, gray, hatched or colored.

General principles

Each of our puzzles has only one solution. All our puzzles are solvable by a sequence of logical reasoning. No multiple choice or unfounded hypothesis is necessary to reach any solution.

To distinguish better between areas, there are four types of print:
• White background.
• Hatched background.
• Shaded background.
• Colored background.
With some browsers, especially firefox, it is advisable to select the option "Print the background", or "Print images".

All irregular jigsaw hexadoku on this site have solutions available for printing. They are all created by sudoku-puzzles-online.com .

Choice of puzzles: Our irregular hexadoku symmetrical puzzles are a little easier to solve than asymmetrical ones. Indeed, the symmetrical ones have an additional constraint - precisely to be symmetrical - so they have fewer empty squares to solve. Also note that the aspect of difficulty is subjective, because different solving techniques suit different people.

Why play irregular hexadoku? Irregular hexadoku is a very hard variation of sudoku. It allows veterans of sudoku to find new visual configurations. The beginner and confirmed levels are solvable by logical deduction. Only the expert level requires you to pencil in the candidates if you cannot see the solution.

Levels to print

• Puzzles "Beginner" are fully resolvable by "Inclusion" while accepting other methods.
• Puzzles "Confirmed" are fully resolvable by "Inclusion" and "Exclusion" while admitting to other methods.
• Puzzles "Expert" are solvable by "Inclusion", "Exclusion" and "Pairs exclusive".
For more details on these three methods for resolution, identical to the regular sudoku, see: General help.

Asymmetrical and Symmetrical puzzles

An irregular 16 x 16 puzzle, is symmetrical when the squares that compose it are arranged equally around the four central squares known as the center of symmetry. This is only esthetic and does not change the resolution mode of the grid. Indeed it is the puzzle that is symmetrical and not the solution. However, the advantage of non-symmetrical puzzles is that, having one less constraint, they allow the elaboration of more difficult problems.

Reproduction Rights

All irregular 16x16 puzzles offered on this site are created by sudoku-puzzles-online.com and these puzzles can be reproduced free on condition that the link to the web site sudoku-puzzles-online.com appears on every reproduced page.