Calculate Your Perfect RAID in Seconds
Find out how much real space you get, which RAID fits your project, and what it will actually cost. No surprises, just precise data.
Real Space
No surprises
Total Cost
3-year TCO
Power Usage
Per year
What is RAID and How Does It Work?
RAID (Redundant Array of Independent Disks) is a technology that combines multiple hard drives into a single logical unit to improve performance, redundancy, or both. Different RAID levels exist, each with its own characteristics of capacity, speed, and data protection.
Interactive RAID Calculator
Storage Configuration
Calculation Results
Raw Capacity
32 TB
Usable Space
16 TB
Redundancy
50%
Capacity Distribution
Rebuild Time Estimated time to rebuild the array after a disk failure. Times >24h increase the risk of a second failure.
Estimated time to rebuild the array after a disk failure. Times >24h increase the risk of a second failure.
Hardware Cost
€756
3-Year TCO
€1,017
Power (per year)
€87
Cost per TB
€63.56
Verdict
Excellent Balance
RAID 1 with 4x 8TB offers complete mirroring with solid redundancy. Your usable 16 TB will cost €1,017 over 3 years including electricity.
Compare RAID Configurations
| Configuration | Usable Space | Hardware Cost | 3-Year TCO | Cost per TB | Best For |
|---|---|---|---|---|---|
| RAID 0 (4x 8TB) No Redundancy | 32 TB | €756 | €1,017 | €31.78 | Speed |
| RAID 1 (4x 8TB) ★ Current Selection | 16 TB | €756 | €1,017 | €63.56 | Balance |
| RAID 5 (4x 8TB) Single Parity | 24 TB | €756 | €1,017 | €42.38 | Efficiency |
| RAID 6 (4x 8TB) Double Parity | 16 TB | €756 | €1,017 | €63.56 | Safety |
Pro Tip
RAID 5 offers the best cost per TB, but requires minimum 3 disks. RAID 1 is simpler and faster for small arrays.
RAID Levels Comparison
RAID 0 - Striping (Maximum Capacity, No Redundancy)
RAID 0 splits data across all disks. Offers maximum capacity and speed, but any disk failure causes total data loss.
RAID 1 - Mirroring (Maximum Safety)
RAID 1 duplicates data across all disks. Offers maximum protection with 50% storage efficiency.
RAID 5 - Striping with Parity
RAID 5 distributes data and parity across all disks. Can lose 1 disk without data loss. Requires minimum 3 disks.
RAID 6 - Double Parity
RAID 6 uses distributed double parity. Can lose up to 2 disks simultaneously. Requires minimum 4 disks.
RAID 10 - Mirroring and Striping
RAID 10 combines mirroring and striping. Offers excellent performance and redundancy. Ideal for databases.
Frequently Asked Questions about RAID
How much usable space does RAID 5 give with 4 x 4TB drives?
With 4 x 4TB drives in RAID 5 you get 12TB of usable space. The formula is (N-1) × disk_capacity, where N is the number of disks. One disk equivalent is used for distributed parity.
What is the difference between RAID 5 and RAID 6?
RAID 5 uses single parity and can tolerate the failure of 1 disk. RAID 6 uses double parity and can tolerate the simultaneous failure of up to 2 disks. RAID 6 is safer but requires a minimum of 4 disks and has slightly lower efficiency.
How many disks does each RAID level require?
RAID 0: minimum 2 disks. RAID 1: minimum 2 disks. RAID 5: minimum 3 disks. RAID 6: minimum 4 disks. RAID 10: minimum 4 disks (even number).
Does RAID replace backups?
No. RAID protects against hardware failures (broken disk) but not against accidental deletion, ransomware, fire or theft. You should always maintain independent backups following the 3-2-1 rule: 3 copies, 2 different media, 1 offsite.
How long does a RAID 5 rebuild take after a failure?
It depends on capacity. A 4TB HDD takes approximately 10-20 hours to rebuild. During reconstruction the array is vulnerable to a second failure. That's why RAID 6 is recommended for high-capacity arrays.