How to play sudoku?


  1. Choose the sudoku difficulty level you like from the drop-down menu at the top. You have 7 levels to choose from very easy to very hard, including magic sudoku.
  2. Fill in the boxes. You can do this by clicking on the box directly or by selecting the box you want and clicking on the numeric keypad on the right.
  3. When you finish filling in all of them, if you have done it right, a message will be displayed congratulating you. If you have doubts about whether you have filled in the sudoku correctly while you are doing it, you can use the self-check function that will warn you of the possible mistakes you make.

If at any time you want to check your numbers you can do so by clicking on the check button. You can also display the sudoku solution or start over. Good luck!

What is Sudoku?


The Sudoku, also known as Südoku, Su-Doku or his doku, is the hobbies (crossword / Puzzle) Japanese fashion of logical type.The history of the Sudoku is quite recent, although in the 19th century some French newspapers already proposed hobbies of similar numbers, it was not until the 70s when the Sudoku developed that we know today in Japan.As of 2005 (when began) this logical game began to be popularly popular.The Sudoku word in Japanese means (sü = number, doku = alone).

Sudoku rules and difficulty

The rules are simple, it consists of a grid of 9x9 cells, divided into 9 quadrants of 3x3, which must be filled so that all rows, columns and quadrants (sets of 3x3 cells) have the numbers from 1 to 9 without any repetition. Obviously, the starting point is a board with some known positions. In general, the less initial numbers a sudoku has, the more complicated it is, but don't be fooled. The difficulty is not only determined by this variable. At we always try to make sure that the sudokus we generate are the most fun and with a perfectly adapted difficulty.

Obviously you start from a started board. In order to be correct, Sudokus must have an unique solution.


In 2012, it was mathematically established that a valid Sudoku must start with at least 17 numbers to have a unique solution. This discovery opened a field of study exploring the total number of possible Sudokus, estimated at 6,670,903,752,021,072,936,960. Scientists have also been interested in optimal solving methods, highlighting algorithms that can solve these puzzles quickly.

The world record for the fastest Sudoku solver, according to the Guinness Book of World Records, is held by Thomas Snyder, who completed a puzzle in 1 minute and 23.93 seconds. Sudoku world championships attract competitors from around the globe, evidencing the popularity and mental challenge the game offers.

Sudoku creation is not limited to number patterns; there are variants that include colors, symbols and even pictures, demonstrating the versatility and adaptability of the game to different cultures and tastes. Some studies suggest that solving Sudoku on a regular basis can help improve memory and mental agility, supporting the maintenance of a sharp mind at all ages.

Despite its apparent simplicity, Sudoku involves mathematical complexities that have been the subject of much academic research. Sudoku variants, such as Sudoku-X, Hyper Sudoku, and Mini Sudoku, among others, keep enthusiasts interested by offering new challenges and enriching the solving experience.


Sudoku not only serves as a pastime, but also fosters the development of key skills in areas such as logic and decision making. By tackling the challenges that each puzzle presents, the player practices and improves his or her ability to analyze and solve complex problems, skills that are transferable to many other areas of life and learning.

In education, Sudokus have been used as a tool to teach programming principles, as they require algorithms and data structures for automated solving. This aspect makes Sudoku puzzles especially useful for computer science students, who can practice programming concepts while searching for efficient solutions to these puzzles.

In addition, solving Sudoku can have therapeutic benefits, such as reducing stress and improving concentration. The need to focus on the game helps people to divert their attention from everyday worries, offering a moment of calm and relaxation. This regular practice can contribute to better mental health, proving that Sudoku is more than just entertainment.

And Magic Sudoku?

The Magic Sudoku is a variant of the traditional sudoku.It is characterized by adding the following restrictions to the original Sudoku:

This Sudoku is more complicated, but also much more challenging and fun, are you up for it?

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