I wish to download 64 bit windows 10 pro OS in a usb drive from media creation tool. How many GB of internet data is required to download. If an HP software download page does not list bit or bit, the system type is bit. Find bit or bit system type and Windows version in Windows File size is a measure of how much data a computer file contains or, alternately, how much storage it consumes. Typically, file size is expressed in units of measurement based on the byte. File transfers (e.g. "downloads") may use rates of units of bytes (e.g. MB/s) in binary rather than metric system, while networking.