Free Sudoku Online

Sudoku is one of the most popular puzzle games in the world. The game is entirely based on logic and is considered one of the best exercises for your brain. The game is played using a 9×9 grid which further consists of 3×3 sections which are partially filled with numbers. The goal of the game is to fill the 9×9 grid with digits between 1 and 9 so that each row and column of the grid contains all the digits between 1 and 9 & there is no repetition of numbers in each row and column.

Sudoku is an excellent brain game which on playing daily, you may see improvements in your brainpower and overall concentration. The game is relatively simple & easy and only involves the logical placement of numbers only. There is no calculation or math skill required.

Sudoku Features:

Difficulty Level

You can choose the difficulty level for your Sudoku puzzle. There are 4 difficulties options available; Easy, Medium, Hard, Expert.

Depending on your knowledge and experience about the game, you can choose the difficulty level that you think is best for your skill level.

Check for Mistakes:

With this feature, the system automatically detects mistakes while you are solving the puzzle. If there are any mistakes then the mistake will be highlighted and you can correct your mistake.

This is a useful feature and helps to solve the puzzle and also learn about your mistakes while solving the puzzle.


When you are confused or lost while solving the puzzle and you can find the possible number to fill in space then you can use the Hint feature that will give you a hint about what to do next.

Clicking on a specific box and then clicking on the Hint button will automatically fill the selected box for you.

Erase & Undo

You can undo your moves as many times as you want to. If there is any move that you made without thinking then you can undo it easily.

If you want to erase a particular number for a particular box then you can select the box and then click on the Erase button to remove that number.

How to Play Sudoku?


The game is played using a 9×9 grid, which further constitutes of 3×3 sections. The grid is partially filled with digits between 1 and 9.


The objective of the game is to fill the 9×9 grid with digits between 1 and 9 so, that each row and column contains the numbers between 1 to 9. Your goal is to fill the grids logically so, that each row and column does not contain a repetition of number from 1 to 9.


The placement of digits is considered incorrect if there is a repetition of the same digit from 1 to 9 in:

  • Row (Fig. 1)
  • Column (Fig. 2)
  • 3×3 grid (Fig. 3)


  1. Focus on a specific part: Row, column, or grid may contain many puzzles inside it. Focusing on a specific part is a good strategy and after completing it, move on to the next one.
  2. Work on Empty Cells: Look for blocks that have 5 or more numbers in them. In most cases, you will easily find the numbers that will be placed in the empty cells.
  3. Filling Candidates: Try to fill in the empty cells with possible candidates that can fit there. Once you put the candidates, then ponder over and eliminate the candidates that don’t fit.

Frequently Asked Questions

Sudoku (数独) is abbreviated from the Japanese suuji wa dokushin ni kagiru which means “the number allotted must remain single”. The first recognized modern Sudoku arrived in the late 1980s in a Japanese magazine called Nikoli, having previously published by French newspapers in 1979 and later in puzzle book named Number Place.

When solving a Sudoku Puzzle then always think logically rather than guessing what number would fit there. The game is purely based on logic and before you enter a number, you should think about the number whether it fits there or not.

It can range from being very simple and easy to very difficult. Easy game version can be solved by beginners while to solve the Very Hard or Evil ones,  you need to follow some sophisticated strategies.

To be considered a “valid” puzzle it must only have one possible unique solution. A puzzle with multiple solution will not be valid.

The best method is to use logic because 99.999% of the puzzles are solved by logic alone. In case, there is no viable option left, you can use guessing or trial & error method as the last resort for solving or you may use our “Hint” feature to automatically fill a cell.

No, it only requires logic and reasoning.

The difficulity of a puzzle is determined by the depth of thinking required to fill up the puzzle. An easy game can be solved using simple logic however Evil version requires more observation and deeper analysis. Because there is a variation in each game some may be harder than the others.

Yes, our web-based game is playable on all major operating systems and browsers. However, we do not have a dedicated Android or iOS app just yet.

We really appreciate you taking your time to report an error, please use our contact form to get in touch with us.

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