The Devil's Calculator
Well reviewed at 96% positive, and only 0% of the way from its all-time low to full price. It rarely gets better than this.
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Steam packages and bundles that include this game
- The Devil's Calculator From $2.99The Devil's Calculator
Packs and bundles (2)
Multi-item packages that include this game
- Logic & Numbers - Best Games -8% From $20.84Logic & Numbers - Best Games
- The Cinq-Mars Media Puzzle Pack From $11.86The Cinq-Mars Media Puzzle Pack
About this game
What this game is, in the developer's words
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
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 .ac.uk email address, get your free steam key by emailing us or following the instructions on our website!
About the 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.Features
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.
Non-Profit
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.
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Price intelligence
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The Devil's Calculator price history and best deals
The Devil's Calculator for PC currently sells from $1.79 at authorized stores. Its all-time low is $1.79, set on 2026-06-27. That is 40% off the $2.99 list price.
Frequently asked questions
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