What is the bare minimum of storage space required for the installation of Windows 10 Home 64-bit?

A 1 GHz or faster processor or SoC (System on a Chip), DirectX 9 or later with the WDDM (Windows Display Driver Model) 1.0 driver, and a least 800×600 display are required for Windows 10. The 32-bit version requires 16 GB of storage, whereas the 64-bit version requires 20 GB. RAM requirements for the 32-bit operating system are 1 GB and 2 GB for the 64-bit operating system, respectively. Remember that these are the minimum needs; the OS will run, but not as well as we have come to expect. In fact, a faster processor, more RAM, and more storage are all reasonable expectations.