Drobolator

Data Roboticslator
Capacity Calculator
Use Drobolator to help you select the number and size of hard drives to fit your needs.
1.
Choose a drive and drag it to any data bay on the Drobo.
80 GB 100 GB 160 GB 200 GB 250 GB 300 GB
350 GB 400 GB 450 GB 500 GB 750 GB 1.0 TB
  
2.
Repeat until Drobo has as much capacity as you want.
3.
Watch how space that's "Available For Data" changes.
Drives: None
Available for data
Reserved for expansion
Used for protection
Overhead