How I Built It: Solving world’s hardest Sudoku with Anaplan Optimizer

edited October 2023 in Blog

About the Author: Tristan Colgate is a Certified Master Anaplanner and Managing Director at Fidenda.

Hi Anaplan Community!

I’m excited to bring a new and fun video to the Community ‘How I Built It’ tutorial series. In my video, I’ll walk through how I used Anaplan’s Optimizer to solve the world’s hardest Sudoku puzzle. In 2012, mathematician Arto Inkala created what’s considered to be the hardest Sudoku puzzle to solve and I’ve never been able to solve it, so I brought in some assistance from my favorite tool!

Optimizer is a really important part of the Anaplan platform. It can be used by organizations to find the optimal solutions to business problems where there is a need to optimize a business outcome that has multiple moving parts and constraints. In doing so it automates business decisions that are impossible for humans to thoroughly analyze. For example, I have implemented it at a media organization that needed to decide which new television program projects they should invest in to maximize ROI, whilst observing other targets such as minimum hours of programming needed per genre.

Check it out and let me know if you have questions!


All the 'How I Built It' tutorials can be found here.


  • Very interesting problem/solution and appreciate the breakdown: especially the final call-out of the binary condition to make the problem linear. Thanks Tristan!

  • Just want to say, this "How I Built It" is great, and the how i built it series is VERY value add. This kind of stuff helps end user model builders a lot, and great for teaching up and coming model builders how to build and think creatively. Please continue to do these and highlight them!

  • Insightful and well presented, well done Tristan.

  • I have been trying to create a sudoku puzzle in Anaplan and validate the inputs. I created a module to input numbers and loaded result too in another module. In order to validate the input, applied CF by comparing inputs to result.

    Your approach helps me to generate result within Anaplan. Thank you very much

  • This is my obtained result by implementing your approach. Thanks

  • Nice job Vamsi - have you tried putting in the Arto Inkala sudoku to check it can solve that one too?

  • Yes, it Solved. As mentioned by you, it took less than a second to solve.