RAID Calculator
RAID Calculator – Calculate RAID Storage Capacity and Redundancy
Planning a RAID (Redundant Array of Independent Disks) configuration without knowing the actual usable capacity can lead to poor performance, wasted disks, or unexpected storage limitations. This RAID calculator helps you quickly calculate usable storage, redundancy, and disk efficiency for common RAID levels used in servers, NAS, and SAN environments.
How This RAID Calculator Works
This tool calculates RAID capacity based on:
- Number of disks
- Disk size
- Selected RAID level
Supported RAID Levels (RAID 0, 1, 5, 6, and 10)
The calculator supports the most commonly used RAID configurations, including RAID 0 for performance, RAID 1 for redundancy, RAID 5 and 6 for balanced storage, and RAID 10 for high-performance enterprise workloads.
Usable Capacity, Parity, and Fault Tolerance Explained
In parity-based RAID levels such as RAID 5 and RAID 6, part of the total disk space is reserved for fault tolerance. This calculator clearly shows how much space is used for parity and how much remains usable.
Whether you are a system administrator, DevOps engineer, or database administrator, accurate RAID capacity calculation is essential before deploying production workloads.
RAID Level Information
Data is split across all drives. Maximum performance and capacity, but no redundancy.
- Minimum drives: 2
- Fault tolerance: None
- Capacity: 100%
Data is duplicated across all drives. Maximum redundancy.
- Minimum drives: 2
- Fault tolerance: n-1 drives
- Capacity: 1 drive worth
Data and parity distributed across all drives. Good balance of performance, capacity, and redundancy.
- Minimum drives: 3
- Fault tolerance: 1 drive
- Capacity: (n-1) drives
Similar to RAID 5 but with two parity blocks. Can survive two drive failures.
- Minimum drives: 4
- Fault tolerance: 2 drives
- Capacity: (n-2) drives
Combines mirroring and striping. Excellent performance and redundancy.
- Minimum drives: 4 (even number)
- Fault tolerance: 1 drive per mirror pair
- Capacity: 50%
When Should You Use a RAID Calculator
A RAID calculator is especially useful when designing or upgrading storage systems.
RAID Planning for Servers, NAS, and SAN
Before deploying enterprise storage, use this RAID calculator to estimate capacity requirements and ensure sufficient redundancy for disk failure scenarios.
RAID Calculator for Database and Virtualization Workloads
For databases such as PostgreSQL and virtualization platforms, RAID configuration directly affects performance and availability. Calculating usable RAID capacity helps optimize disk I/O and prevent storage bottlenecks.
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