Play Sudoku online for free
Master advanced techniques and play Sudoku in English without registration or other difficulties.
Play Sudoku without registration
Want to become the king of puzzles? Our site will help you achieve this goal! You’re sure to find the right challenge for any skill level here. Solve Sudoku puzzles on Sudoku Kingdom with pleasure – without registration or other restrictions!
Is Sudoku Kingdom free?
Yes. Sudoku Kingdom is completely free to play Sudoku, with no limit on the number of games you can play.
How do I play Sudoku online?
The Sudoku Kingdom project has puzzles for all skill levels. For example, you can choose Sudoku Easy, Sudoku Medium, Sudoku Hard and even Super Hard.
- Any row of Sudoku contains numbers from 1 to 9
- Any Sudoku column contains numbers from 1 to 9
- Any 3×3 quadrant contains numbers from 1 to 9
You need to play Sudoku every day to make good progress. The higher the difficulty level, the more effectively your skill will grow.
Whether you’re a beginner or an experienced player, Sudoku Kingdom will definitely not disappoint you 😉
Gaming functionality of Sudoku Kingdom
For the convenience of the gameplay on the site created a convenient interface with many functions:
- The “New Game” button. By clicking on it, you can create a new combination of numbers on the playing field.
- Buttons “1”-“9”. Select the desired cell on the playing field and press the desired digit.
- Clear Button. Removes the selected digit.
- Hint Button. After clicking on the field, numbers will appear in some cells that can take up space in the cell. Press “Solve All” button – after that all empty cells will be filled.
- The “Game difficulty” option. Several difficulty levels are currently available: Sudoku Easy, Sudoku Medium, Sudoku Hard and even Sudoku Super Hard.
- The “Clear Field” button allows you to completely reset all progress and build your own version of Sudoku (may be needed if you want to solve a particular version of Sudoku).
Tips on how to play Sudoku
Solving simple sudoku is usually not difficult. All you have to do is fill in all the cells with the only possible choices.
But if you try to solve more complicated puzzles, the game becomes much more interesting. In such cases you need to hypothesize and make logical conclusions to come to the only true solution. For example, you can assume that in a certain cell there must be a certain number, and then analyze the possible variants of verification. In doing so, you may have to reject your assumptions if they turn out to be wrong.
But of course, there are certain methods and strategies that can help you solve complex sudoku more efficiently.
1. Bare Singles
This method involves focusing on one number in a row, column, or block, and excluding it from all other cells. Once that number has been excluded from all other cells in that area, it can be filled in the remaining cell. This is why this method is called “naked singles”-one number is exposed in a particular area, and this allows it to be filled in the corresponding cell. This method allows you to simplify the solution process, especially if you are faced with complex Sudoku puzzles.
2. Hidden Singles
“Hidden singles” are actually “naked singles” that can be found during the game when you add a new digit to a row or column. The method is to look for cells in which only one number can appear, and that number cannot be found in other cells in the same row, column, or block. This helps uncover other cells (since you already know that one number cannot be used in that area).
3. Bare pairs/triples/fours in sudoku
If a block (square, row, or column) has two cells in which only two numbers can be written, then obviously those numbers can be excluded from possible choices for other cells in that block.
The method is to look for cells in which there can only be two/three/four unique numbers in a square, row, or column. If you have a cell where only two numbers can appear, you can check other cells in the same row, column, or block to see if there are other cells where those same two numbers can appear. This trick can be used not only with pairs, but also with three or four cells.
4. Hidden Pairs in Sudoku
Hidden pairs is a very useful strategy that is, in some ways, the inverse of bare pairs. The method is to find cells in which only two numbers can appear, and those numbers cannot be used in other cells in the same row, column, or block.
For example, if you have two cells in the same block in which only two specific numbers can appear, you might conclude that those two numbers can only be used in those two cells, and so you can remove those numbers from the other cells in that block.
5. The unnamed pair rule
The method is to find two cells in the same block, row, or column in which only two numbers can appear. These numbers cannot be used in other cells in the same row, column, or block. So you can conclude that the numbers you want can only be used in these two cells, and therefore you can remove them from the other cells in the sector.
6. Pointing Pairs
If you have two cells in the same block, row, or column in which only two specific numbers can appear, you can conclude that the two numbers can only be used in those two cells. Using this rule, you can remove those two numbers from the other cells in that block, row, or column. The advantage of the pointing pair method is that it allows you to quickly calculate the possible values for the cells
Note that these numbers must not be in other cells in the square, according to the unnamed pair rule
Advanced ways to solve Sudoku for free
1. X-Wing
The “X-Wing” (or “X-Wing”) method is one of the sudoku puzzle solving methods that can help you find the correct values for the cells. This method is based on finding two rows or columns in which only two cells in each row or column contain the same number. At the same time, these two cells are at the same positions. For example, if only two cells in two rows contain the same number and those cells are at the same positions relative to two columns, then you can conclude that the number can only be used in four of those cells. Using this rule, you can remove this number from the other cells that are at the intersection of these rows and columns.
2. Y-Wing
The Y-Wing method is similar to the X-Wing method. It is one of the complex methods of solving Sudoku, which allows you to determine the logical connections between triplets of cells. This method uses two intersecting “wings” and a third cell that forms a hypothetical pair. The essence of the method is as follows: we find two cells in which only two candidates are possible. Then we find a third cell which is connected with both found cells and has a common candidate. This candidate is the only possible candidate in the third cell. We can then exclude that candidate from the other cells associated with that candidate. Because Y-Wing is a fairly complex method, it is used by experienced players.
3. Swordfish method
The method is based on the X-Wing rule, but instead of two rows and two columns, it uses two different areas, such as two blocks and two rows or two blocks and two columns. The essence of the method is that we look for two pairs of candidates that occur in only two areas. Then we find the intersection of these two areas, where the common candidate is the only possible one in the third cell. In this way, we can exclude that candidate from the other cells associated with that candidate. The Swordfish method allows us to solve even the most complex sudoku puzzles because it finds hidden candidate pairs that are not always visible at first glance. In addition, this method is a great tool for practicing logical thinking and improving sudoku solving skills.