The Devil's Calculator is a new, non-profit math game by the creator of Synonymy that proves a sophisticated, challenging and educational indie puzzler for numberphiles and lovers of logic and brain teasers
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7 user reviews - Need more user reviews to generate a score
Release Date:
Jan 28, 2019

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Recent updates View all (3)

March 19

Major Update: Version 3.0 with Free DLC

Hi Everyone!

So thrilled and grateful for the positive feedback we've been getting on the game - we never expected it would gain such a following. We've been working around the clock to add tons of new features asked for by the community and lots of stability improvements, all outlined below!

  • Free DLC section added with levels by famous mathematicians like James Tanton and James Grime!
  • Tons of changes under the hood for vastly improved performance and responsiveness, - bottom to top refactoring plus lots and lots of bug fixes
  • Ability to create and play community levels without beating the game.
  • Community level system completely overhauled, now runs on Math.js:: this means levels can be far more sophisticated (i.e. complex numbers) with less programming and more intuitive syntax. Also far more stable and safer.
  • Ability to copy formula history to the clipboard (by popular demand :steamhappy:)
  • More seamless Wolfram alpha integration
  • More intuitive menu design
  • Lots of other subtle improvements and optimizations.
  • Better help resources, including a new User Guide

I still feel such a moron about the two hour downtime on launch day :steamfacepalm: (since isolated so it can never happen again). Really excited to share this new version with all of you and I appreciate your support and interest more than you realize.

Please contact me with any issues or questions at
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February 27

Improvements for Online Level Creation

Hi everyone! Due to popular demand, we're integrating an advanced math library (math.js) so that users can build even more sophisticated levels, easier. We're going to be switching over from javascript to the math.js eval syntax (which is much simpler) and we're including support for ternary operations so you can still do things like, (if the input is even, do this, else do that). This will add support for complex numbers, and more advanced features detailed here. This methodology will also be far more secure for building and downloading levels.

Because we're switching over to this system imminently, I have disabled writing to the central server temporarily, meaning you will not be able to upload levels within the game until we release an update, (we're aiming for early next week). This has our full attention and we're confident it will be a much better system in the long run. In the meantime, please submit levels here or send them to me directly at and I'd be happy to program them for you, and consider them for inclusion as DLC.

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Free Steam Key for Students & Teachers

Our 501(c)(3) non-profit is committed to making our games freely accessible for educational purposes. If you are a current student or educator with a .edu or email address, get your free steam key here:

About This Game

An evil calculator has its normal arithmetic operators replaced with sadistically obscure functions. Using logic and a bit of algebra, you must work backwards to interpolate and use these corrupted operators to compute the 'number of the beast', 666, in order to purge the calculator of its demons and continue on. Non-profit and open-source, The Devil's Calculator is a highly original indie game that's as addicting as it is educational. Accessible to numberphiles and math novices alike, the first 20+ levels are 100% free to play and enjoy in the game's Demo.


Each level has you decipher the function of a mysterious operator and use it to calculate the number of the beast to progress. The game features advanced graphing mechanics and access to various resources to help you interpolate and solve the innovative and creative function level design. As you progress in the game, players unlock the ability to create their own levels and play challenges others have created - including free DLC levels crafted by the game's creators, educators and mathematicians. With hand drawn artwork and a charming story, the Devil's Calculator is an addicting and gratifying puzzle experience.


The Devil's Calculator was made by Cinq-Mars Media is a 501(c)(3), a non-profit organization developing technology to support scientific research related to human safety and education, and to make such technology and research available on a charitable basis.

System Requirements

Mac OS X
SteamOS + Linux
    • OS: Windows 7 and later
    • Processor: An Intel Pentium 4 processor or later that's SSE2 capable.
    • Memory: 512 MB RAM
    • Storage: 320 MB available space
    • OS: OS X 10.9 and later
    • Processor: An Intel processor that's 64-bit
    • Memory: 512 MB RAM
    • Storage: 320 MB available space
    • Processor: An Intel Pentium 4 processor or later that's SSE2 capable
    • Memory: 512 MB RAM
    • Storage: 320 MB available space

What Curators Say

7 Curators have reviewed this product. Click here to see them.

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