How much disk space would you have if you use four 2 terabites drives in a raid 5 configuration?

In a RAID 5 configuration, the total usable disk space is calculated by taking the total capacity of all drives and subtracting the capacity of one drive for parity. With four 2 terabyte drives, the total capacity is 8 terabytes (4 x 2 TB). Subtracting the capacity of one drive (2 TB) for parity leaves you with 6 terabytes of usable disk space.