SudokuNut

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Free Printable Sudokus

What is Sudoku?

Sudoku is a puzzle game designed for a single player. It is a logic puzzle, not a math puzzle.

A Sudoku puzzle is all numbers, laid out in a grid nine wide and nine high. These 81 boxes where digit go, are called cells.

The puzzle starts with some cells filled in and some cells empty. It is up to the player to determine what numbers go into the empty cells to complete the puzzle. Once all the cells are filled in, then you have successfully completed the puzzle. But there are rules.

The Rules

Sudoku puzzles contain only numbers 1 through 9. Only one of each number can appear in a row, a column, and a block.

You can see that in the yellow row, there is only one of each number. There are no duplicates. Every row has to be like this. In addition, every column as well as every box can only have one of each number.

Once the puzzle is complete, the entire board will have exactly nine instances of each number.

Difficulty Ratings

Sudoku puzzles should not be rated by how many numbers are on the board, they should be rated by how many methods it takes to solve the puzzle. That's what I do at SudokuNut. Many Sudoku puzzles are rated incorrectly, so when I made this site, that was one of my primary goals.

My rating system uses a human-like move-based system that uses solving techniques that a human would use. The harder the solving techniques required, the more difficult the puzzle rating.

That said, you may find a hard puzzle easy, and an easy puzzle hard, but that is because you are human. You may not spot a specific number one day, but another day, you see it right away. That's one reason why puzzles are intriguing.

Other Points of Interest

One thing to mention is that each true Sudoku puzzle must have only one solution. That was another one of my goals when I created SudokuNut. Every puzzle you play at SudokuNut only has only one single solution.

Another thing, there are over 6 billion trillion puzzles possible. Crazy huh? So we will never run out of puzzles. And to be sure, SudokuNut cranks out thousands of new puzzles all the time!

Who is Behind all This?

Just me. One guy. Having fun.

I just tackled a Sudoku Puzzle for the first time and it grabbed me. I was a bit addicted right away and became a Sudoku Nut. Then as I was doing a puzzle, I thought to myself, I think I can code up a site that let's people do puzzles the way I do. So I gave it a go, and before I knew it, I had it working.

I hope you all enjoy the site. If you have any suggestions or find anything strange, or you just want to say hi, drop me a note anytime.

Oh, and how do you say Sudoku? Try this... Sue - Dough - Koo. :)

Cheers,
Dave
SudokuNut.com

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Instructions

Every Sudoku has a unique solution. Enter numbers so that each row, column and box contains the numbers 1 through 9 with no repeats.

Double-click to enter/remove an answer.

Single-click to add/remove notes.

Right-click to circle notes.

Change pencil color if you need to guess and progress.

Comment on each puzzle.

Auto-save and timer are enabled.

Resize grid to your preference.

Getting a hint or viewing the solution will cancel the timer.