Play Sudoku Online

Sudoku Online: Play Free Puzzles of Different Difficulty Levels

Here you can play Sudoku online for free. If you want, finish the puzzle directly in your browser or print it out and solve it with paper and pen, the choice is yours. We have puzzles in several difficulty levels, from easy Sudoku to hard Sudoku, so everyone can find a challenge that’s just right.

An open laptop on a wooden desk displaying an online Sudoku puzzle on the screen. The puzzle grid is partially filled with numbers

Sudoku a Strategy Game

Sudoku is a logic-based game where you have to fill in a 9×9 grid of squares with numbers. The grid is divided into nine smaller regions of 3×3 squares each. Some squares already have numbers, while others are blank. Your goal is to find the missing numbers in the blank squares, without repeating any numbers in the same row, column, or region.

Sudoku Rules

The rules of Sudoku are simple. As we’ve already mentioned, the game board consists of a grid with numbers and empty squares. The task is to fill the empty squares with numbers, and the goal is for each row and column to contain a unique number between 1-9. Furthermore, no number can appear more than once within the same row, column, or section (the smaller 3×3 square in the large puzzle). Based on the existing numbers, you need to find the right places for the remaining ones.

The rules are relatively simple, and there is only one valid solution for each puzzle. The challenge is to fill in the empty squares without breaking the above rules. For more detailed instructions on how to play Sudoku, visit

Easy and Hard Puzzles for Beginners and Experts

Sudoku comes in different difficulty levels, from easy to really hard. You can choose the difficulty level you want to play with. We have Sudoku for beginners as well as for experts. There are four levels of difficulty to choose from:

  • Easy: These puzzles have a rating of up to 500 and require relatively simple techniques to solve.
  • Intermediate: These puzzles have a rating between 500-800 and require a few more techniques to solve.
  • Hard: These puzzles have a rating between 800-1100 and require advanced techniques to solve.
  • Expert: These puzzles have a rating over 1100 and require even more advanced techniques to solve.

Choose the level you find most fun! Depending on your mood, you may prefer a simple Sudoku, a challenging one, or even a very tough one.

If you’re curious about the exact difficulty level of a Sudoku, you can check under the game board. There, you can see the puzzle’s difficulty rating. The higher the value, the harder it is.

Sudoku Tips

Sudoku can be solved in different ways, so you need to find the method that works best for you. For a harder Sudoku, you have to combine multiple methods to reach the solution. Below are some of the basic methods that can be combined in various ways. Feel free to use these Sudoku tips to improve and become a better puzzle solver. If you’re a beginner, this little Sudoku school is definitely recommended as it answers one of the most common questions: How do you solve Sudoku?

Solution Methods

  • Single Number: If a square can only contain one number, place it.
  • Single Position: If a number can only be in one place in a row, column, or box, place it.
  • Pairs: If two numbers can only be in two squares in a row, column, or box, no other number can be in these squares. All other candidates can then be eliminated from these squares.
  • Triples: The same as for pairs, but with three numbers and squares.
  • Single Row/Column: If two boxes with common rows or columns must have the same number in two of the rows or columns, the third box must use the remaining row or column. This method becomes particularly useful when all three squares in a row or column within a box are filled.
  • Dot System: To systematically find the unique solution, it can help to place a dot in each square corresponding to a number from 1-9. Imagine each square is divided into nine squares, i.e., three rows and three columns. Let number 1 correspond to a dot in the top left corner, number 2 a dot in the top row second column … number 5 in the center, etc. From this, you can then systematically find the solution. This may be needed in later stages of harder Sudoku.
  • Candidates: The same as the dot system, but place small numbers with a pencil along the top edge of the square instead.
  • X-Wing: If a candidate appears exactly twice in the same row or column, and the same candidate appears exactly twice in another row or column, and on the same row/column as the first candidate, the number must stand in one of these places. All other instances of this candidate in the same rows, columns, or boxes can therefore be eliminated.

How Difficulty Is Determined

The difficulty of a Sudoku depends on which and how many of these solution methods you need to use to solve the puzzle. The more difficult solution methods you need to use, the harder the puzzle is. A common misconception is otherwise that you can determine the difficulty level based on the number of pre-filled numbers in the game board, but this is not the case. The puzzle can be difficult even if many numbers are filled in.

Play Sudoku Online – Instructions

With our program, you can easily solve Sudoku online. It’s also free. To enter a number, you must first select a square with the mouse. Once you have selected a square, you can use the keyboard to enter a number. You can also hold down the mouse button and drag the mouse up and down to scroll through the numbers.

Our program also has several smart features to make it smooth and fun to play. For example, you can choose the size of the game board, check solutions, and get hints. If you’re stuck, you can choose to have parts of the puzzle solved or have the whole solution presented. Another option if you’re stuck is to save the Sudoku for later and solve another one in the meantime. When you’re ready, just open the saved puzzle to continue.

If you want, you can also start over from the beginning by clicking the reset button. This is much faster and smoother than manually removing every number you’ve filled in.

Check and Hints

If you want to check the solution or get hints, you can choose between the following buttons:

  • Hint: marks the next square to solve. Also shows the technique required to solve it. If you quickly press the hint button again, the next square will also be displayed.
  • Check: provides immediate feedback on whether the entered numbers are correct or not.
  • Solve: gives you three options to help you solve the puzzle:
    Solve one step: places a number (the next logical step)
    Show all steps: shows all the steps to a solution
    Show solution: places all remaining numbers
A section in a Sudoku puzzle where candidates are filled in an empty box. The candidates are 2, 9 and 8 and these are circled in pink.

Note Candidates

We also want to draw your attention to the note feature in our program, which makes it possible to note candidates in each square, i.e., fill in different numbers that could potentially stand in the square. You access the function by double-clicking on the empty square. You can note up to nine candidates per square. When you’ve decided on one of the numbers, just double-click on it, and it’s automatically filled in the Sudoku. Of course, you can also remove candidates from the notes if you’ve ruled them out. Click on the number and then on 0 to remove it.

Try Sudoku for Free With Us

With us, you can always play free Sudoku online. You can play as many times and as often as you want, it costs nothing, and you don’t need to register to play. If you’d rather use paper and pen, you can print out our Sudokus for free.

You can also use our program to solve Sudokus you’ve found elsewhere and let the program solve them. The program supports most logical techniques for solving puzzles, so all puzzles except the most advanced should be solvable by the program. You just need to fill in the numbers and click solve, and the program takes care of the rest.


Over the years, there have been many variants of number games similar to Sudoku, but the version we play today is commonly traced back to the 1970s in the US. It was invented by an American, Howard Garns, in 1979 and published by Dell Magazines under the name Number Place. The game did not become a hit there, it was not until it reached Japan in the 1980s that it became really popular and was eventually named Sudoku, which means ”single number” in Japanese. Since then, the game has spread around the world and also found its way onto the Internet as a web game.

Like crosswords, Sudoku is now a common feature in various daily newspapers and magazines. Some offer, for example, Sudoku of the day to readers who want to entertain themselves with number puzzles and keep their brains in shape.


How do you play Sudoku?
Answer: You can, for example, play Sudoku online for free here with us. The game involves filling the game board’s empty squares with the numbers 1-9. The tricky part is figuring out which number to place where since the same number can only appear once in each row, column, and section square. Through logical thinking and testing, you can work your way to a correct solution. The harder the puzzle you’ve chosen, the more techniques you’ll need to use to come to the solution.

Does it cost anything to play?
Answer: No, it’s completely free to play Sudoku online with us.

Do I need to create an account?
Answer: No, you play directly in the browser and don’t need an account to play.

Do you have easy Sudokus?
Answer: Yes, we have Sudoku with different levels of difficulty. You choose whether you want to play easy, medium, hard, or expertly hard puzzles!

Practice makes perfect, so play Sudoku for free online with us and improve your skills.

Source: Wikipedia