Storage
RAID Calculator
Calculate storage capacity, efficiency, and fault tolerance for different RAID configurations. Plan your disk arrays with accurate capacity estimates.
RAID Level
Data striped with distributed parity.
Min Disks: 3
Read: Good ((N-1)×)
Disk Configuration
Disk Layout
1
2
3
4
Data Disk
Capacity Analysis
Usable Capacity
0 GB
of 0 GB raw
Storage Efficiency0.0%
Raw Capacity
0 GB
Parity/Mirror
0 GB
Fault Tolerance
None
Hot Spares
None
Quick Comparison
| Level | Efficiency | Tolerance |
|---|---|---|
| RAID 0 | 100% | 0 |
| RAID 1 | 50% | 1/pair |
| RAID 5 | (N-1)/N | 1 |
| RAID 6 | (N-2)/N | 2 |
| RAID 10 | 50% | 1/pair |
Best Use Cases
- RAID 0:Temp/scratch data, non-critical high-speed storage
- RAID 1:OS drives, boot volumes, small critical data
- RAID 5:General file storage, read-heavy workloads
- RAID 6:Large arrays, archival, high availability needs
- RAID 10:Databases, VMs, write-intensive applications
RAID Level Comparison
| RAID | Min Disks | Capacity | Fault Tolerance | Read Speed | Write Speed |
|---|---|---|---|---|---|
| RAID 0 | 2 | 100% | None | Excellent | Excellent |
| RAID 1 | 2 | 50% | 1 disk/pair | Good | Normal |
| RAID 5 | 3 | (N-1)/N | 1 disk | Good | Moderate |
| RAID 6 | 4 | (N-2)/N | 2 disks | Good | Lower |
| RAID 10 | 4 | 50% | 1 disk/pair | Excellent | Good |
N = number of disks. Capacity formula shows usable storage as a fraction of raw capacity.
Hot Spares
- Purpose: Standby disks that automatically replace failed drives
- Rebuild: Begins immediately, reducing vulnerability window
- Recommendation: 1 hot spare per 10-20 disks
- Cost: Dedicated disks not used for storage capacity
Best Practices
- Same size: Use identical disk sizes in an array
- Different batches: Avoid disks from the same manufacturing batch
- Monitor health: Watch SMART data for early failure signs
- Backup: RAID is not a backup - maintain separate backups