Typefi Thermo: Can you crack it?


Ever played a cryptic sudoku?

In the early days of the 2020 COVID-19 lockdowns, several members of Typefi’s Australian team became addicted after discovering The Miracle Sudoku, a weirdly compelling viral video of a puzzle-master sitting in a gloomy English attic solving a sudoku with just two given numbers.

As it turns out, there are many ‘cryptic’ variations on the classic sudoku. Ben “Baz” Vale, Typefi Senior Engineer, recently decided to take his sudoku obsession one step further by setting these challenging puzzles himself.

So, from the mind of Baz, we present Typefi Thermo. Can you crack it?

An incomplete sudoku puzzle overlaid with thermometers which place additional constraints on the solution.

Click here to play it in your web browser!

(The linked puzzle also contains a ‘Solve’ option, but if you’re having trouble getting started, we recommend checking out the rules and hints below first.)


The normal rules of Sudoku apply—each row, column and square (9 spaces each) needs to be filled out with the numbers 1-9, without repeating any numbers within the row, column or square.

If you’ve never played sudoku before, you can find basic instructions and solving techniques at masteringsudoku.com.

In the Thermo Sudoku variant, ‘thermometers’ are overlaid on the grid. Numbers in the thermometer sections must increase in value from the bulb end (the numbers do not need to be consecutive).


Trouble getting started? Click below to expand the hints.

How did you go? Let us know in the comments! (We’ll hold all comments for moderation—no spoilers!)

Ben Vale

Engineer | Australia

Ben is a software engineer with 15 years of industry experience and is currently working on Typefi’s Research and Development team. He specialises in rapidly prototyping ideas and experimenting with new and emerging technologies.

Prior to Typefi, Ben worked in the video games industry creating games for all ranges of hardware. When he’s not coding he enjoys travelling, hiking and the beach. He is also known as Baz (which is short for Ben).