No. RAID improves availability, not backup protection.

Why differs from NAS UI?

Vendors use different overhead and filesystem assumptions.

Can I compare SSD and HDD?

Yes, for rough multipliers only.

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RAID Calculator

Estimate usable capacity, fault tolerance, and rough throughput for RAID setups.

RAID Level Disk Type Disk Count Per-disk Capacity (TB)

Usable capacity: -

Fault tolerance: -

Estimated sequential speed: -

RAID feature quick table

Level	Min disks	Usable capacity	Fault tolerance	Notes

Overview

Estimate RAID usable capacity, fault tolerance, and rough read/write multipliers across RAID 0/1/5/6/10/50/60 and RAIDZ1/Z2.

How to use

Select RAID level and disk type.
Set disk count and per-disk size.
Run calculation and review capacity/tolerance/speed.

Examples

RAID 5

Input: 4 disks × 2TB

Output: Usable approx 6TB, 1-disk tolerance.
RAID 10

Input: 6 disks × 1TB

Output: Usable approx 3TB with mirrored-pair constraints.

Notes

Values are estimates and controller dependent.
Rebuild performance and random I/O are not fully modeled.
Always keep backups regardless of RAID level.

FAQ

Is RAID a backup?: No. RAID improves availability, not backup protection.
Why differs from NAS UI?: Vendors use different overhead and filesystem assumptions.
Can I compare SSD and HDD?: Yes, for rough multipliers only.

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Guides

RAID Level Comparison Guide