RAID Calculator
Calculate RAID array capacity, usable storage, read/write speed gain, fault tolerance, and cost across RAID 0, 1, 1E, 5, 6, 10, 50, and 60 levels. Free online RAID calculator with charts and breakdowns.
About This Calculator
The RAID Calculator helps you evaluate and compare different RAID (Redundant Array of Independent Disks) configurations for your storage needs. Select a RAID level, enter your disk specifications, and instantly view usable capacity, performance gains, fault tolerance, and cost metrics.
The calculator supports ten RAID levels: RAID 0 (striping for maximum performance), RAID 1 (mirroring for redundancy), RAID 1E (striped mirroring for odd drive counts), RAID 5 (single parity for balanced capacity and protection), RAID 6 (double parity for enterprise protection), RAID 10 (striped mirrors), RAID 50 (striped RAID 5 arrays), and RAID 60 (striped RAID 6 arrays). Capacity formulas follow the standard industry definitions from the original RAID paper by Patterson, Gibson, and Katz (UC Berkeley, 1988) and IBM documentation on RAID properties.
Regional Support
India: Uses ₹ (INR) with India-appropriate defaults.
United States: Uses $ (USD) with US-appropriate defaults.
United Kingdom: Uses £ (GBP) with UK-appropriate defaults.
Frequently Asked Questions
What is RAID and why use it?
RAID (Redundant Array of Independent Disks) combines multiple hard drives into a single logical unit to improve performance, fault tolerance, or both. RAID 0 maximizes speed by striping data across drives, RAID 1 mirrors data for redundancy, RAID 5/6 use parity for a balance of capacity and protection, and nested levels like RAID 10, 50, 60 combine striping with mirroring or parity for enterprise-grade storage solutions.
What is the difference between RAID 5 and RAID 6?
RAID 5 uses single parity and can tolerate one disk failure, providing (N-1) drives of usable capacity. RAID 6 uses double parity and can tolerate two simultaneous disk failures, providing (N-2) drives of usable capacity. RAID 6 requires a minimum of 4 drives compared to RAID 5's 3, and offers better protection at the cost of reduced usable capacity.
How many drives do I need for each RAID level?
RAID 0 and RAID 1 require a minimum of 2 drives. RAID 1E requires 3, RAID 5 requires 3, RAID 6 requires 4, RAID 10 requires 4 (even number), RAID 50 requires 6 (multiples of 3), and RAID 60 requires 8 (multiples of 4). The calculator validates your drive count against these requirements.
What is capacity utilization in RAID?
Capacity utilization is the percentage of total raw disk capacity available for data storage after accounting for parity, mirroring, or hot spares. RAID 0 offers 100% utilization, RAID 1 offers 1/N × 100%, RAID 5 offers (N-1)/N × 100%, RAID 6 offers (N-2)/N × 100%, and RAID 10/60 offer 50% utilization.
Which RAID level gives the best read and write performance?
RAID 0 offers the best performance with Nx read and Nx write speed gains because data is striped across all drives with no parity overhead. RAID 10 offers Nx read and N/2x write speed. RAID 5 and 6 offer (N-1)x and (N-2)x read speed respectively, but write speed is limited to approximately 1x due to parity calculation overhead.
How is the cost per usable TB calculated?
Cost per usable TB is calculated by dividing the total cost of all drives (number of drives × cost per drive) by the usable capacity in TB. RAID levels with higher utilization (like RAID 5) generally have lower cost per usable TB than levels with lower utilization (like RAID 1 or RAID 10), though other factors like performance and fault tolerance should also guide your choice.
Is this RAID calculator free?
Yes, it is completely free to use with no registration or hidden charges.
Can I compare different RAID levels?
Yes, you can change the RAID level dropdown and disk parameters to compare usable capacity, performance gains, fault tolerance, and cost across different RAID configurations. The results update instantly so you can evaluate RAID 5 vs RAID 6, RAID 10 vs RAID 50, or any other combination.