If Sudoku Primer and the YouTube channel have helped you, consider donating a little

Thanks in advance for your support!

Sudoku Primer & Complete Reference

Learn all about sudoku on this site


Welcome to the Sudoku Primer website. You will find lots of sudoku information on this site.

This website goes hand-in-hand with the Sudoku Primer (Harold Nolte) YouTube channel. You will be able to learn quite a bit about how to solve sudoku puzzles using this website and the YouTube videos together.


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Click on the menu picture of 'hamburger' menu with the word menu to its right sideicon at the top of every page for all sudoku pages on this site.

Here are some quick links to common pages.

Coffee (as in buy me a)

If you have learned from this website and the YouTube videos, please consider buying me a coffee. Click on the purple button above and follow the directions.


Thank you all who have bought me a coffee or two recently. I feel your kindness and generosity. I am glad you feel this website and YouTube logo channel are worth it. Please know that it is appreciated!


Sudoku basics teaches you sudoku rules and the basics of the game. It is worth looking at even if you already know how to play sudoku. You just might learn some new things.


Sudoku Primer has videos on YouTube with Sudoku lessons ranging from techniques to solving entire puzzles. There are almost 300 videos with new ones added all the time. Here are two videos

Getting Started Video

Watch this video to understand how sudoku puzzles work and how to solve an easy puzzle

Solving a very difficult puzzle

This video shows a very complex way to break through a diabolical puzzle and finish solving it

Video Index

This page has an index of the different techniques each video talks about. Refer to this page to find specific techniques you would like to learn about.

How do you pronounce primer?

Why is primer pronounced the way it is in the videos? Find out why.


The Challenges page tests your knowledge and skills by showing you a partially completed puzzle with a circled number. Your challenge is to figure out how that number got there, or why it is the only number that fits in that cell. Try it out, it just may improve your solving skills!

Sudoku Myths

Learn about eight sudoku myths and why they're not true.

Did you Know?

There are 6,670,903,752,021,072,936,960 unique sudoku combinations! See OEIS A17739 - See the research page for more information

If Sudoku Primer and the YouTube channel have helped you, consider donating a little

Thanks in advance for your support!

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