RAID Calculator

Size your disks from the usable capacity you need.

Enter the usable capacity you’re targeting and the number of drives you have available, then compare RAID levels side by side to see the disk capacity each one requires.

How this works

Most RAID calculators start from the drives you’ve already chosen. This one starts from the outcome: tell it the usable capacity you’re targeting and how many bays you have, and it works backwards to the disk capacity each RAID level would need to get there — so you can compare RAID 0, 1, 5, 6, 10, 50 and 60 against the same target before you commit to a drive size.

Compare RAID levels

Level Disk needed Raw total Usable result Efficiency
RAID 5 6 TB 48 TB 42 TB 88%
RAID 6 8 TB 64 TB 48 TB 75%
RAID 10 10 TB 80 TB 40 TB 50%

Recommended appliance for 8 drives

Magnetar MA-HR12-H

12 bays, 3.5″ SAS/SATA.

  • Disk capacities are rounded up to the nearest commercially available size for the selected drive type (SATA/SAS HDD, SATA/SAS SSD, or NVMe U.2).
  • RAID 1 follows the classic definition: a mirror of exactly two drives.
  • RAID 50 and RAID 60 automatically select a group configuration (2, 3 or 4 groups) based on the number of drives entered.
  • Appliance recommendations are based on maximum bay count per drive-type family. Configurations marked “Pending Confirmation” await final bay-count validation from the product team.

Need help validating a configuration?

Speak with our technical team to confirm your sizing before you order.