genuinely one of the most invaluable resources on the internet, thank you so much for hosting this for free

Thanks, Andrew,

Just opted for a one year membership. I really appreciate your site; you've taught me most of my sudoku solving strategies. I look forward to checking out the rest of your puzzles.

Thanks,
Mawf

We have been using Sadman Sudoku for many years and loved it. We have changed to Chromebox and can no longer use Sadman's software.
Your Sudoku software works very well on Chromebox, BUT, I cannot find the solutions written out. Where are they?

Thanks for your great work!

Phil

What a very excellent site, this has really helped to take my Sudoku solving skills to the next level (but I'm still very much a learner)
regards Sapper JJ

Thanks for the great site Andrew, and good on you for keeping it ad free. Made a long-overdue contribution today - appreciate your work! Larry

Thanks Andrew. I've been using your excellent KS solver quite a lot :))

If you do Bitcoin, you might consider putting a "receive address" on your Donate page similar to the bottom right of this page:

https://bitcointicker.co/stamp/btc/usd/12hr/

Optionally, you could generate a new address, occasionally, so that it's not so easy to snoop what donations have been made (or have not ;) -- perhaps automate the address change (?)

Cheers,

Dave B (UK)

I really appreciate your all effort for this webpage.
I'm from South Korea, Ph.D student in CS (developer) and also a puzzle lover interested in many of number-based puzzle like Sudoku (with so many variations), Kakuro, Nonogram, TetraSquare, Bridges, and so on.
My recent dream is to apply SuDoKu global competition and try to learn so many nice sudoku solving techniques.
In Korea, there is a general wiki named 나무위키(NamuWiki, 'Namu'=tree) having a document about the techniques but lack of some advanced techs.
Today I've found this page, shocked about your step-by-step solver with all tech documents and really being encoraged to enjoy sudoku harder than before.
Thanks again and hope eternity of this page.

I've been pushing my limits with advanced sudoku since lockdown, and sudokuwiki.org has been such a great resource. Thanks for providing it. Hope to donate again later. Joe D

Many thanks for all the effort that you must have invested into programming the algorithms/heuristics and the website, which is a joy to visit.

Finally, I GET Sudoku thanks to this app!

Thank you for all of the great information. Your explanations are simple, straightforward and easy to understand. I've been trying to figure out X-Wings and XY Wings for a while now, your instructions and examples were a huge help to me.

Your puzzles make my day good. One killer and a Jigsaw

Thank you so much.
I learned a lot from your comprehensive and superb explanations.

I have been enjoying your site for a number of years now, and have vastly increased my ability to solve tough Sudoku puzzles. I finally realized I could make a donation for it - thank you so much!

Thanks a lot for all the work