I have a terrible PC.
Intel Pentium D 3.2 Ghz Dual core
1 GB of Ram
Whatever version of integrated graphics came with the pc.
This game gets a little rough when Firefox takes up 1/3 of my RAM.
My computer is closing in on 10 years old, If you have a decent PC from the last 4-5 years, you should be able to run this. I'd imagine even most netbooks and Windows 8 tablets would run this just fine.