How to solve Sudoku.

Sudoku puzzles are square grids made of little cells, 9 to each row and column. So there are 81 little squares or cells. Some of these cells have numbers already filled in. At least 17 of these little cells will have numbers in them. 17 is the minimum number required to make sure that the puzzle has only one solution.

The large grid is also divided into 9 smaller squares each with 3 cells across and 3 down.

The object of the game is to fill each row, 3x3 square, and column with numbers from 1 to 9. No number should be repeated in any 3x3 square, column, or row. That’s it. Simple.

Some tips to begin with:

• Start with a small 3x3 square that ideally contains 5 or more numbers. 
• Look at the adjoining two squares.
• Does any number missing from your selected square occur in the two adjoining squares? If it does it will be in two different rows in each of the two adjoining squares.
• This leaves one row in which the number must be placed, in the square you’re looking at.
• If two of the squares in this remaining row in your square are already filled, the missing number can be filled in in the remaining vacant cell in that row.

Go on in the same way with the rest of the puzzle. The easiest sudokus can be solved with just this technique.

Did you notice? You didn’t need to make any calculations–there’s no arithmetic involved at all. 

All you need is to clear thinking and concentration. 

It sounds easy, and it can be… but it can also get fiendishly difficult. 

But that’s when it gets interesting!

What’s described above is one among many techniques that sudoku fans call ‘scanning’. Most easy puzzles can be solved by one or another method of scanning.

There are many other methods and techniques and tips and tricks to learn on your way to sudoku expertise. Some of the simpler ones are singles, intersections, naked subsets, hidden subsets, and so on. There are more advanced techniques as well, such as x-wing, swordfish, jellyfish and other types of fishes. 😄

There will soon be a detailed section on how to play sudoku on this website. This will be really useful if you want to learn more about sudoku and to get better at it. We’re planning to make it downloadable as a pdf, so keep checking back to see when it’s ready.

Why do Sudoku Puzzles? 

And is online sudoku better than offline?

 Sudoku Puzzles are Great Fun!!

But there’s much more to them. Doing Sudoku puzzles can:

• Improve your thinking skills. Develop more, sharper cognitive skills
• Help to ease tension from a stressful day;there’s nothing so refreshing as an activity that’s absorbing enough to take your mind off the day’s events. Sudoku can definitely do that. 
• It’s simple and inexpensive.  All you need is a pencil and eraser. If you’re doing it online, you don’t even need that. 
• Young people will find that their problem-solving skills, their ability to concentrate and think logically could improve.
• Older folks find sudoku a great way to keep their brains in trim, warding off memory loss, and keeping mentally fit.

Online sudoku or offline?

Playing sudoku online  can be slightly faster because sudoku apps usually have functions that do the bothersome 'house-keeping' tasks for you, such as filling in and updating  candidates*, and so on.  And it's faster to tap a number than to write it down.

Our free online sudoku app has time-saving features such as auto-filling  and updating  of candidates.

But many people prefer the good old pencil-and-paper method. If you're among them, we have you covered—in our printable sudoku section. Download and print the puzzle, and solve it offline!

We also have sudoku books on our Amazon page that you can order and have delivered to an address of your choice.

But whether you're playing sudoku online or offline, the rules are the same and the thinking skills you need are the same.

If you’re new to sudoku puzzles, welcome. Welcome to greater powers of focus and concentration. welcome to greater brain health and well-being.

And welcome to many hours of absorbing fun with our free online sudoku puzzles!

(*More about candidates in our soon-to-come tips and tricks section)