RAID Calculator
Calculate RAID capacity, redundancy, performance, and cost for all RAID levels. Visual drive layouts and comprehensive analysis for storage planning.
RAID Configuration
Min: 3, Max: 16
Optional drives for automatic replacement
Drive Layout
D
Drive 1: data
D
Drive 2: data
D
Drive 3: data
P
Drive 4: parity
Data
Mirror
Parity
Spare
Usable Capacity
6.0 TB
75.0% efficiency
Fault Tolerance
1
drive can fail
Total Cost
$400.00
$0.07/GB
Raw Capacity
8.0 TB
4 × 2.0 TB
RAID 5 (Distributed Parity)
Data and parity striped across all drives. Good balance of performance, capacity, and redundancy.
Performance Profile
Read: Good ((N-1)×)
Write: Moderate (parity overhead)
Use Case
Most popular RAID level. Great for file servers and general storage where one drive failure protection is sufficient.
RAID Level Comparison
| Level | Min Drives | Efficiency | Fault Tolerance | Performance |
|---|---|---|---|---|
RAID0 | 2 | 100.0% | 0 | Excellent (N×) |
RAID1 | 2 | 25.0% | 1 | Good (2×) |
RAID5 | 3 | 75.0% | 1 | Good ((N-1)×) |
RAID6 | 4 | 50.0% | 2 | Good ((N-2)×) |
RAID10 | 4 | 50.0% | 2 | Excellent (N×) |
RAID50 | 6 | 66.7% | 2 | Very Good |
RAID60 | 8 | 50.0% | 4 | Very Good |
About this tool
Compares usable capacity, fault tolerance, and performance characteristics across RAID levels, RAID 0, 1, 5, 6, 10, and the nested 50/60 arrays, for a given drive count and size.
When you’d use it
- Sizing a NAS or storage server build before buying drives.
- Comparing the capacity cost of RAID 6 against RAID 10 for the same fault-tolerance target.
Frequently asked questions
- Does this account for real-world rebuild time or drive failure rates?
- No, it's capacity and theoretical fault-tolerance arithmetic only. Actual rebuild risk depends on drive size, array age, and controller behavior that this calculator doesn't model.
- Is RAID a backup?
- No, RAID protects against a drive failure, not against accidental deletion, ransomware, or damage to the whole array, so you still need a separate backup regardless of which level you run.
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