Free online RAID storage calculator. Calculate RAID capacity, usable space, redundancy, and fault tolerance for RAID 0, 1, 5, 6, 10, 50, and 60. Pure client-side, no ads.
This RAID calculator helps system administrators, IT professionals, and home lab enthusiasts plan storage configurations. Enter your RAID level, number of disks, and disk size to instantly see usable capacity, redundancy overhead, and fault tolerance. All calculations happen in your browser with no data sent to any server.
RAID (Redundant Array of Independent Disks) combines multiple drives for better performance, capacity, or redundancy. It protects against data loss from disk failures and/or improves read/write speeds.
RAID 0 for maximum speed (no redundancy). RAID 1 for critical data with 2 disks. RAID 5 for good balance of capacity and redundancy with 3+ disks. RAID 6 for higher redundancy with 4+ disks. RAID 10 for maximum performance + redundancy with 4+ disks.
RAID 0: 2+, RAID 1: 2+, RAID 5: 3+, RAID 6: 4+, RAID 10: 4+ (even), RAID 50: 6+ (multiple of 3), RAID 60: 8+ (multiple of 4).
RAID 0: N × disk size. RAID 1: 1 × disk size. RAID 5: (N-1) × disk size. RAID 6: (N-2) × disk size. RAID 10: (N/2) × disk size. RAID 50: (N - N/3) × disk size. RAID 60: (N - 2×N/4) × disk size.
Most RAID implementations use the smallest disk size in the array. Larger disks are truncated to match. For optimal capacity, use identical disks.
Storage efficiency is the percentage of raw disk space that is usable for data storage. Higher is better for capacity, but lower efficiency means more redundancy protection.
No! RAID protects against disk hardware failure but not against data corruption, malware, accidental deletion, or natural disasters. Always maintain separate backups.
RAID 50 stripes across multiple RAID 5 groups (1 disk fault tolerance per group). RAID 60 stripes across multiple RAID 6 groups (2 disk fault tolerance per group). RAID 60 offers higher redundancy at the cost of more overhead.