In terms of game file size, you will need at least 2 GB of free disk space available. To play Not Heaven you will need a minimum CPU equivalent to an Intel Core 2 Duo T7250. Not Heaven system requirements state that you will need at least 1 GB of RAM. Provided that you have at least an NVIDIA GeForce 8200M G graphics card you can play the game.
Not Heaven will run on PC system with Windows 7 and upwards. Additionally it has a Mac version.