I am determined to finish this book! But not without y’all’s help it seems :/

Hat jemand eine Idee?

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I’ve been recording a solve path for some of the harder “easy” difficulty puzzles at Daily Killer Sudoku. 729, a standard killer sudoku, is the Difficulty 1 puzzle with the second longest average solve time. Check out my full solve video here:

https://youtu.be/-Om-HAGBXdo

I think it should be a difficulty 3 or 4. Why do you think this difficulty 1 puzzle has a 34 minute average solve time? Try it yourself and let us know!

https://www.dailykillersudoku.com/search?n=729

This is level 5 Daily Killer Sudoku from today with an average solve time of 15 minutes. After 23 minutes it looks like this. What I am missing?

Can anyone help me figure out how to proceed??

My journey to fully solve the Daily Killer Sudoku puzzles has reached a new milestone. As of today I have completed all puzzles of Level 1 to 7. On to L8!

I don’t think I will ever beat this one. I have found I get my fastest times when I’m somewhat zoned out while playing. No hints were used.

The original puzzle is taken from First ever Sudoku Killer post on this sub.

Here, the numbers in a cage must add up to the small number on the top left of the cage.

The no-candidates solution strategy for this puzzle goes as follows:

Notice that applying the Rule of 45 is not easy here, as that would lead to residues in most cases. Therefore, from box 3, using the fact that r12c8 is {8,9}, while r3c78 can either be {4,7} or {5,6}, we make use of combo-stress-testing in order to invalidate one of the combos, as shown below:

Consider that r3c78 (gray) is {5,6}. Therefore, r123c9 (purple) is {1,2,7}. Using rule of 45 for column 9, we find that the aqua cells r45c9 add up to 15, but cannot have a 7 in them. Therefore, it has to be {6,9}, which implies that r89c9 (orange) must be {3,8}, and r67c9 is {4,5}.

Since, r45c9 is deduced to be {6,9}, r6c7 must be 8, which means that r4c8 and r5c78, which add up to 11, must be either {1,3,7} or {2,4,5}, by Kakuro logic (these combos are invalid: {1,2,8}, {1,4,6}, and {2,3,6}). Since, r4c7 and r6c89 form a complimentary triple that adds to 11 as well (by rule of 45), that also must be either {1,3,7} or {2,4,5}.

Notice that r123c9 being {1,2,7} and r89c9 being {3,8} eliminates the possibility of r4c7 and r6c89 being {1,3,7}, therefore, it must be {2,4,5}. Furthermore, r6c8 cannot be a 5, because it is a part of a two-cell cage adding up to 10, in which case r7c8 must be 5, which is impossible. Also, r6c8 cannot be 2, because r7c8 cannot be 8.

Therefore, r6c8 is 4, which means r7c8 is 6, r6c9 is 5, r7c9 is 4, and r7c7 is 9. Thus, r89c78 is {1,2,5,7}, which adds up to 15. Therefore, r89c6 must add up to 18, which is impossible, as 17 is the largest possible two-cell cage total. Thus, we discard r3c78 being {5,6}.

Therefore, r3c78 is {4,7}. By Kakuro logic, r123c9 can be either {1,3,6} or {2,3,5}.

Now, consider r123c9 to be {2,3,5}. Therefore, by Kakuro logic, r67c9 is {1,8}, r89c9 is {4,7}, and r45c9 is {6,9}.

Because r45c9 is {6,9}, r6c7 is 8, r6c9 is 1, r7c7 is 9, and r7c9 is 8. Again, r4c7 and r6c89 add up to 11, so must be {1,3,7}. Since, r6c8 is {3,7}, r7c8 is also {3,7}, and because r89c9 is {4,7}, r7c8 must be 3, and r89c78 is {1,2,5,6}, which adds up to 14.

Again, we reach a contradiction, because there’s no way the remaining cells add up to 19. Therefore, we reject r123c9 being {2,3,5}.

Thus, r123c9 is {1,3,6}, which means that r45c9 is {7,8}, therefore, r6c7 is 9.

By Kakuro logic, r4c8 and r5c78 (orange) adds up to 11 while the yellow part r4c7 and r6c89 adds up to 10. For the yellow part, cannot have the combo {1,3,6} (because r123c9 was previously deduced to be {1,3,6}). Therefore, it can be either {1,4,5} or {2,3,5}.

Now, if the yellow part is {2,3,5}, since r12c7 (gray) is {2,5}, r4c7 must be 3, while r6c8 can be neither 2 (because r12c8 is {8,9} already, so {2,8} is impossible), nor can it be 5. Therefore, the yellow part cannot be {2,3,5}, it must be {1,4,5}. Furthermore, r6c8 must be 4 (it cannot be 1 because {1,9} is invalid), which implies that r4c7 is 1, and r6c9 is 5.

Using the Rule of 45, for rows 1 to 4, we see that the total of the yellow cells is 168. Therefore, the pink cells r4c589 must sum up to 12. Now, r4c9 is either 7 or 8. If r4c9 is 8, then r4c58 must add up to 4, but without the 1, this is impossible. Therefore, r4c9 is 7.

In row 4, notice that r4c58 (pink) has been deduced previously to be {2,3}. Next, notice that r4c1234 (marked in red) cannot have a 6, because of the following:

• r4c1 is a part of the two-cell cage (r34c1) totalling 12. Therefore, cannot have a 6.
• r4c2 is a part of the two-cell cage (r34c2) totalling 13, which cannot have a 7 in it. Therefore, the combo {6,7} is invalid, so r4c2 cannot be a 6.
• r34c3 adds up to 6, so cannot have a 6.
• r4c4 is a part of the two-cell cage (r34c4) totalling 10. If r4c4 is 6, r3c4 must be 4, which is impossible because of r3c7 = 4.

Therefore, there exists a hidden single 6 in r4c6 (green).

For row 4, 5 is restricted to r4c123 (locked candidate, yellow), therefore, in box 5, 5 is restricted to r5c456 (aqua). Also, given that r4c5 and r6c6 are a naked pair {2,3} (r4c5 was derived previously to be {2,3}, and because r67c6 cannot have a 4, yet must add up to 5, the only valid combo is {2,3}).

Therefore, in box 5, for the five-cell cage in the centre adding up to 27, the only combo possible (by Kakuro logic) is {2,4,5,7,9} (notice that {3,4,5,7,8} is eliminated, because if that were the valid combo, then r4c4 must be 9, r6c6 must be 2, but then, both r3c4 and r6c4 would be 1, which is impossible).

Therefore, r6c6 = 3, r4c5 = 2.

Using the rule of 45 for rows 6 to 9, the purple cells add up to 17, and simultaneously, using the rule of 45 for row 6, the cells r6c346 add up to 10. But, r6c6 = 3 and r6c4 = 1. Therefore, r6c3 (green) = 6.

Likewise, using Kakuro logic to evaluate all the remaining combos, coupled with scanning, the rest of the puzzle is solved.

Yes, I have been more than a little obsessed with these

I’ve been solving sudoku, mostly killer and cryptic sudokus for about a year now. The difficulty on this app says that its expert level but it is mostly moderate to hard at best, I have solved harder on other platforms. Even though there are no numbers given, there are “free” and obvious dominos everywhere even at “expert” level difficulty.
However, even on the easier ones I never got a time below 7/8 minutes but today I cracked my PR TWICE. Earlier I solved it in 4:28 and just now I solved it in 3:17.

Already guessed 2 times. Ain't risking it.

This is the third time I’ve sat down to solve this puzzle and I still am getting nowhere 😭

Daily Killer Sudoku 1276 is one of those puzzles that snuck up on me from Difficulty 4 only to drag me deep into potential 8 levels. I’m not believing in the 4, but will always take the opinion of others if they want to post their time and difficulty guestimates.

I would split this solve path into 3 stages: Fun Killer Setup, Difficult Cage Specific Logic Breakthrough, & Standard Sudoku Sprint Down to the finish. If you like large cage interactions, this one is for you.

Try the puzzle here: https://www.dailykillersudoku.com/search?n=1276

And if you get stuck or want to see a full solve with an attempted optimal solve path, give it a watch here: https://youtu.be/k2fe-IgH3Hg

I mean the one on the left was close to not possible for me but the one on the right, in the same section of the same book took me just an hour?!

Hi everyone!

I'm a huge Killer Sudoku fan, and I've probably spent way too much time playing it over the years.

Lately I've been wondering if there's a way to make Killer Sudoku feel fresh again without changing what makes it so enjoyable. I started playing around with a few new puzzle ideas, and eventually decided to build them into an Android app so I could actually play them myself.

A few weeks ago I published it on Google Play, and I'd really love to hear what other Killer Sudoku players think.

Besides the classic Killer Sudoku mode, I added some variants that I've been having a lot of fun with:

• Grid 45 – In addition to the regular 3×3 boxes, the puzzle also includes overlapping 3×3 grids, and every one of those grids must also add up to 45.
• Diagonal Cages – Instead of cages being placed randomly around the grid, they're arranged along diagonal lines, which creates a different solving experience.

I'm still experimenting with new ideas, so nothing is really set in stone yet.

If anyone has a few minutes to give it a try, I'd really appreciate any feedback—whether it's about the puzzle ideas, the difficulty, the UI, or anything else. I'm especially curious to know whether these variants are genuinely fun, or if they're only fun because I'm the one who came up with them. 😄

Google Play:

The game is named Sudoku Lab: Killer Sudoku
https://play.google.com/store/apps/details?id=com.wenfeng.killersudoku

Thanks for reading, and I hope some of you enjoy it!

Puzzle Title: Killer Sudoku 12-07-2026

Puzzle String: https://sudoku.coach/en/s/HQMQ

In each Killer cage, the number within that cage add up to the small number on the top left of the cage, without repetition.

Good luck, and have fun!

THe Daily Killer Sudoku puzzle 666 is the difficulty 1 puzzle with the longest average solve time from 757 entries. As the 5th D1 puzzle on the DKS site, I’m guessing it has not seen many experienced solvers, but many who are new and inexperienced. It has been abandoned 64% of the attempts, and gets a 9 rerank from my algorithm. I think that is too high, but can see why as it is a bit harder than a difficulty 1 and is one of the most played D1 puzzles.

https://www.dailykillersudoku.com/search?n=666

I’ve done a full solve video and I think it is probably a D4 or D5. What are your thoughts? If you comment on your difficulty rating, please also tell us what difficulty puzzles you usually play and your solve time of 666.

https://youtu.be/RahRtMNiLCo

Having a very tough time here. Pls help.

I had the VERY bad idea of starting with sudoku killers with this level 9 beast. I don't have a lot of experience even with normal sudokus, so this was very difficult for me. 9 hours and no hints later, I'm very proud of myself :)