RAID Storage Calculator
Calculate usable storage capacity, efficiency, and fault tolerance for RAID 0, 1, 5, 6, and 10 configurations.
Results
What is it?
RAID (Redundant Array of Independent Disks) combines multiple physical drives into a logical volume with varying trade-offs between performance, capacity, and redundancy. The level you choose determines how much capacity is sacrificed for protection.
How to use
Enter the number of drives, the capacity of each drive, and choose a RAID level. The calculator shows usable storage, efficiency (usable divided by raw), and how many drives can fail before data loss occurs.
Example scenario
You have 4 x 4 TB drives. RAID 5 gives 12 TB usable (75% efficiency, 1 drive failure tolerated). RAID 6 gives 8 TB usable (50% efficiency, 2 drive failures tolerated). RAID 0 gives 16 TB (100% efficiency, 0 tolerance — any failure loses everything).
Pro tip
RAID is NOT a backup. It protects against drive failure, not against accidental deletion, ransomware, fire, or theft. Always follow the 3-2-1 rule: 3 copies of data, on 2 different media types, with 1 offsite. RAID 10 offers the best read/write performance with redundancy but costs 50% of raw capacity.