About Sudokion

I’m new to Sudokion. What kind of puzzles should I start with?

We suggest that you start with Sudokion6 and Sudokion7 puzzles rated Easy. When you’re confident, you could move on to our Sudokion8 and Sudokion9 rated Moderate and Medium. If you’re familiar with Sudoku you should have no difficulty playing Sudokion. You may find the videos on this page helpful.

How many different types of games are there and what are the rules?

At present there are more than 40 different Sudokion ranging from the 6×6 Sudokion, with 36 cells, through to the Sudoku-size 9×9 Sudokion (81 cells). The essential rules are the same as those governing Sudoku. The RULES i button on the playing screen brings up the rules specific to the particular puzzle.

Why do Sudokion puzzles have different-coloured squares?

The primary reason for differently-coloured cells is that they guide the eye to see which cells go in which clusters. A second reason is that some cells can only be identified as belonging to a particular cluster by virtue of their colour. Here’s a good example … without coloured cells it would be impossible to determine which cells go with which clusters.


Some puzzles don’t have many clues, do they?

Compared with Sudoku, certainly. Because they have a more complex structure than Sudoku many Sudokion can have a unique solution with fewer clues than Sudoku. So, for example, to achieve a unique solution a traditional Sudoku must have at least 17 clues. This Sudokion requires only eight clues to produce a unique solution.


I’ve noticed that the grid structure of some Sudokion is very complex.

Yes, that’s correct. We want Sudokion to be available to everyone, from absolute newcomers who prefer easier puzzles with relatively straightforward grids through to diehard Sudokionistas who live for excruciatingly difficult puzzles with diabolically-complex grid structures.

I’m interested to know how you rate the puzzles

As we make all our puzzles by hand, we also rate them all by hand. At times it’s difficult to decide which challenge level to apply to a particular puzzle. How do you compare the degree of challenge of a puzzle that has a series of reasonably but not too difficult logic problems against another that is generally easy but has one whopping big logic problem which if unsolved defeats the solver? In those cases it’s a matter of judgement, and we know very well that one assessor may award a different challenge level to another. Over the long term we look at how long it takes our subscribers to complete a particular puzzle, and if necessary we adjust the challenge level accordingly.

How are skill points awarded for each puzzle?

Sudokion Skill Points are awarded for completed puzzles, taking account of the size of the puzzle, its challenge rating and the time taken to solve it. In the case of puzzles rated Easy, Moderate and Medium, extra seconds are added to the elapsed time every time that you use the CHECK ? button. The maximum number of points available for each completed puzzle varies, from a maximum of 2 points for a very Easy Sudokion6 through to 50 points for a Sudokion9 rated Extreme.

Some of the challenge ratings have different levels. For example, “Easy” ranges from very easy to easyish. 5 points is the maximum score for a very easy Sudokion8 while you can score as many as 8 for an easyish Sudokion8. The formula we use to calculate your Skill Points is a closely-guarded secret but let us assure you that we have done our very best to make it as fair as possible.

Maximum PointsEasyModerateMediumDifficultExtreme

Playing Sudokion Online

How do I play the game?

Select a cell and use either the number pad below the puzzle or your keyboard. When you want to fill it you can either select WRITE for a definite (“penned”) number or NOTES. If you select NOTES you can pencil as many numbers as are available; so, for instance 1, 2, 3, 4, 5, 6 and 7 for a Sudokion7. To delete a penned number you can either overtype or use the UNDO button or DELETE on your keyboard. To remove all the numbers from a pencilled cell you can select and delete. To remove a particular pencilled number insert the same number again.

BUTTONS allow you to:

  • WRITE: “pen” one number (you can change it later if you want)
  • NOTES: “pencil” as many numbers as are available
  • ERASE: clear all numbers in the selected cell
  • RULES: check the rules
  • CHECK: check whether you have made a mistake (Easy, Moderate and Medium only)
  • TIMER: check your time
  • RESTART: clear all entries and start again
  • EXCLUDE: note numbers that may not occupy a cell (Difficult and Extreme only)
  • MENU: allows you to exit, PRINT and SHOW SOLUTION and has links to other parts of the website

How do I print out a puzzle?

Press the MENU button and then PRINT. You will need to save the puzzle to your computer first.

Why does the clock start at minus 15 seconds?

We give you 15 seconds to read the rules and get yourself settled. If you’re quick you can commence the puzzle while the clock is ticking down.

I noticed recently that when I went out of a puzzle the clock showed 5’16” but when I went back to the same puzzle the clock showed 4’33”. Why?

The clock resets itself to the moment that you made your last entry, in this case at 4 minutes 33 seconds.

What does the MENU button do?

If you press the MENU button under the puzzle you leave the puzzle to give yourself a range of options: return to puzzle, check your playing history or your statistics, print the puzzle, check the solution or start a new puzzle. Or, if you like, you can press the orange SUDOKION banner and return to the home page.

Your Subscription

How can I be confident of the security of my credit card details?

We don’t retain any of your credit card details ourselves. All card-card transactions are conducted via an accredited third-party provider.

How do I upgrade from a free trial to a subscription?

Go to the Subscribe page and select your subscription plan.

How do I change my email address and password?

If you are already a subscriber go to the My Account page and complete the appropriate field.

How do I extend or cancel my subscription?

Go to the My Account page and select either “Renew your subscription” or “Amend/cancel your subscription”. You can cancel your subscription at any time until you play a puzzle.

How do I get further support?

Go to the Contact page and send us an email. We will respond as soon as we can.

Future Projects For Sudokion

How frequently will new puzzles be added and who do I contact to get more puzzles?

When you subscribe you have unlimited access to every Sudokion we make. We are making more puzzles in our current range every week. From time to time we create new types puzzles in the Sudokion range and once they’re tested and we’re happy with them we add them to the mix.

Are there any Sudokion competitions? Do you offer prizes?

We intend to start the Sudokion Competition, open to all current subscribers, some time during 2016. You can compete using your own name, a screen alias or anonymously. Most days the puzzle will range from easy through to difficult but at least once a week the puzzle will be extremely difficult. A leader board for every day’s puzzle will be posted within a few days. Prizes? … satisfaction at having competed and perhaps making it to the leader board.

Do you have any other plans for extending Sudokion?

Yes, some time during 2016 we will offer subscribers a range of Super Sudokion puzzles. They’ll be absolutely perfect for holidays and long weekends. As they’re much too large to play on most screens they will be available in books easily downloaded from our website.

We will also launch Advanced Sudokion, which will allow subscribers who know their way around Sudokion to be more specific in the selection of their next puzzle.

Then there’s Sudokion Enigma, a for-the-moment secret project (naturally) that will appeal to dedicated Sudokionistas who don’t mind having us mess with their brains.