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RAID Capacity Calculator



Redundant Array of Independent Disks (RAID) is a data storage technology that combines multiple physical hard drives into one logical unit for improved performance, data redundancy, and increased storage capacity. Calculating the capacity of a RAID is essential to ensure that you have enough storage space to meet your needs. In this blog post, we will discuss how to calculate RAID capacity.

RAID Types

There are several RAID types available, and each type has a different way of calculating its capacity. The most commonly used RAID types are:


RAID 0 combines two or more disks into one logical unit, and data is striped across them. This RAID type does not provide any data redundancy, and if one drive fails, all data is lost. The capacity of RAID 0 is calculated by adding the capacity of all the drives.


RAID 1 mirrors two or more drives, which means that data is written to two or more disks simultaneously. This RAID type provides data redundancy, and if one drive fails, the data can be recovered from the other drive. The capacity of RAID 1 is calculated by dividing the total capacity of all the drives by two.


RAID 5 uses block-level striping with parity data distributed across all the drives. If one drive fails, the data can be recovered from the parity data. The capacity of RAID 5 is calculated by subtracting the capacity of one drive from the total capacity of all the drives.

Online RAID Capacity Calculator


Query raid card info

Most RAID card manufacturers provide their own utilities to query RAID card information. These utilities usually provide more detailed and specific information about the RAID card and the connected hard drives. Some popular RAID card manufacturers and their utilities are:

  • Adaptec: Adaptec Storage Manager
  • LSI: MegaRAID Storage Manager
  • Dell: OpenManage Server Administrator
megacli -AdpAllInfo -aALL
ssacli ctrl all show detail
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