Solver App for Android
Strategies for Popular Number Puzzles
Page:2024 1 2 3 4 5 6 7 8 :2023 2022 2021 2020 2019 2018 2017
2015 2014 2013 2012 2011 2010 2009 2008 2007 2006

Feedback and Questions

I've received a lot of interesting comments and questions from Sudoku fans over the last few years and this page is where I try to answer them. I'm also directing Str8ts feedback here. Please feel free to drop me a note on the side of the page. Or you can email me directly at .

Post a Comment or Question here...
Your Name or 'Handle'

Part of the World you're from

Email Address (optional) so I can reply directly if necessary (it will not be displayed here)

Any Sudoku you want to publish here for easy loading into the solver - 81 characters, use '.' or '0' for unknowns.

public - comment/question will be added to feedback column
private - email comment/question directly to Andrew Stuart, don't display here

Comment, question or feedback:

Enter these letters
Please enter the
letters you see:

Many thanks to all the people who have helped improve the solvers and strategies with their feedback!

Saturday 1-Jun-2024

... by: rocky, earth

Hello, I am using this site regularly to learn the sudoku tricks. Today, I tried kenkodu solver as 6 x 6 killer sudoku. But after few steps, it stuck on the candidates removing part and dont proceed further. I tried ctlr+f5 and clearing cookies. It didnt solve. Also can you also add email this board option in kenken solver also? Thanks

Andrew Stuart writes:
Hi rocky. I'm having problems with the 6x6 solver at the moment. Should install just like the 9x9 but for some reason won't do it. Am continuing to work on it.

Friday 31-May-2024

... by: Barbara Trauer, Australia

OKAY Solvers have been updated to version 2.16!
You will need to download the latest page and scripts, which is simple to do. Press the keys [CRTL]+[F5] together to force a reload. If this does not work, you can clear your cache.

Can’t do this on my ipad

Andrew Stuart writes:
Wish I had an ipad to test with! What I do is update a version number on the included scripts which normally invalidates any cached version the browser has. Sometimes it can be a bit sticky on the ipad. Keep reloading the page?

Friday 31-May-2024

... by: Kate McCullough, Maryland USA

Why the change in the format of the jigsaw printable version of the puzzles? It’s totally unusable as there is no space to write the candidates. Am I missing something?

I really enjoy your puzzles and am grateful for your website , but this change is very disconcerting as I am now having to hand copy the puzzles. Not a big deal in the general scheme of things, but still an annoyance.

Thank you for your help.


Andrew Stuart writes:
My bad. Was deleting a bunch of old stuff to keep things same. Jigsaw was linking to an old style sheet.
Check now!

Tuesday 28-May-2024

... by: Roger, California

KenKen solver stopped working: all browsers, all OSes. Ver 2.16. Ctrl+F5 no help. Click on "Take a Step" does nothing. Click on "Grader" gives

Problem grading this puzzle.
cl=36, sp=0, as=-nan(ind), w= 0.0

Please advise...thanks

Andrew Stuart writes:
Yep I broke it yesterday. Publish in haste, repent at leisure. Try now, CRTL+F5

Monday 27-May-2024

... by: Glen, MN

Recently you changed the color of the tries from Bold Red to Red. This completely changes the strategy of the game. Please return to normal Bold Red.

Andrew Stuart writes:
Hi Glen. Need more info - not sure what you are referring to. Leave an email so I can respond directly

Saturday 25-May-2024

... by: Stephen Fairchild, United Kingdom

Load Sudoku:

On classic Sudoku hidden singles does not trigger the broken grid error message when two (or presumably more) values are selected for the same cell.

With the supplied broken 17 clue grid both 5 and 9 are highlighted for F9 then the 9 is promoted without regard to the 5.

Andrew Stuart writes:
Okay I’ve put in a trap for this. [CRTL]+[F5]
Situation I’m certain should only occur if the puzzle is broken (multiple solutions)

Thursday 23-May-2024

... by: Martin, Germany

Load Sudoku:

The first board is classified as unsolvable, however, the second board, with more clues, is solvable according to the solver. All strategies are used. Is this intended, because there is not a unique solution or is this a bug?
Here are the boards:

Andrew Stuart writes:
The solver only works logically if there is a unique solution since there is no logical way to choose one over the other if there are multiple solutions. Solution Count is there to check you have a valid puzzle.

Tuesday 21-May-2024

... by: Mary, Canada

I just tried to restart the Daily Kakuro and the restart button doesn't work.
Love your puzzles!!! - Thanks. Mary

Andrew Stuart writes:
Fixed! Found the problem. Refresh until you see v2.03. Thanks for the report

Sunday 19-May-2024

... by: BdR, Netherlands

A local newspaper has a prize Kenken puzzle every week, and I was unable to solve it by hand. I wanted to check with this solver because I feel like I'm overlooking some method or approach (to be clear, I wasn't going to cheat and send in an automated-solution). However, when I press "step" after 2 steps it gives the error message "Some cages are larger than 6 cells. 7 is not legal for a valid KenKen 6x6 puzzle" even though it should be solvable.

In the same paper from previous week, this Kenken puzzle is also unsolvable somehow, the auto-solver finds the same top-left digits but I don't know which step to do next LINK

Andrew Stuart writes:
Yes I don't know what to do with cages that > 6 cells. I consider them a different type of puzzles. I might look at the code and see if I can adapt it. Does make the puzzle a lot more difficult

The KenKen solver lags behind the Sudoku solver when it comes to the most difficult puzzles. Still some strategies to be discovered. The problem is too many candidates at the start. Very few Sudoku strategies work with so many

Saturday 18-May-2024

... by: Kaz, Netherlands

i am unable to edit candidates in the color sudoku, pressing enter does nothing, pressing outside of the cell, returns everything as it was before (other cells too)

Andrew Stuart writes:
Not sure what you are experiencing. Do the other solvers work? Colour Sudoku works for me. Maybe uncheck the "auto-clear" tickbox? Write with an email so I can contact you directly.
Page:2024 1 2 3 4 5 6 7 8 :2023 2022 2021 2020 2019 2018 2017
2015 2014 2013 2012 2011 2010 2009 2008 2007 2006
Thank-you everyone for all your questions and contributions.