NAS pSEO Landing

10x 16TB RAID-Z2 NAS Calculator | Usable TB

Estimate usable TB, parity overhead, and fault tolerance for 10x 16TB in RAID-Z2. Includes reserve planning for NAS and homelab arrays.

Capacity Snapshot

Raw Capacity

160.00 TB

Usable Capacity

115.20 TB

Fault Tolerance

2 drives

Efficiency

80.0%

Popular TrueNAS default for medium arrays; dual-parity with good safety margin. This scenario applies a 10% filesystem reserve.

Run Interactive Calculator →

Alternative Mode Comparison

Mode	Usable	Tolerance	Efficiency
RAID 5	129.60 TB	1 drive	90.0%
RAID 6	115.20 TB	2 drives	80.0%
RAID 10	72.00 TB	1 drive per mirror pair*	50.0%
RAID-Z1	129.60 TB	1 drive	90.0%
RAID-Z2	115.20 TB	2 drives	80.0%

NAS Cluster Guides

NAS Hub RAID Level Compare RAID Capacity Matrix Planning Quick Sheet RAID Selector NAS FAQ

Related Long-Tail Calculators

2x 4TB RAID 1 2x 6TB RAID 1 2x 8TB RAID 1 2x 10TB RAID 1 2x 12TB RAID 1 2x 14TB RAID 1 2x 16TB RAID 1 2x 18TB RAID 1 2x 20TB RAID 1 3x 4TB RAID 1 3x 4TB RAID 5 3x 4TB RAID-Z1 3x 6TB RAID 1 3x 6TB RAID 5 3x 6TB RAID-Z1 3x 8TB RAID 1

Sequential Long-Tail Navigation

← Previous: 10x 16TB RAID-Z1 NAS Calculator | Usable TB Next: 10x 18TB RAID 1 NAS Calculator | Usable TB →

FAQ

Is RAID-Z2 still practical with 16TB drives?

It can be practical, but larger drives increase rebuild windows. Validate parity choice and backup policy before committing to the final layout.

How much effective storage does 10x 16TB RAID-Z2 provide?

This NAS planning scenario estimates 115.20 TB usable after a 10% reserve from 160.00 TB raw.

Can this calculator replace real-world benchmark and rebuild testing?

No. Use this page for pre-purchase sizing, then validate with workload benchmarks, SMART health policy, and a tested restore plan.

Why include a 10% reserve when planning NAS available space?

Keeping free space improves filesystem behavior for snapshots, metadata, and write performance. Full arrays often perform worse and rebuild more slowly.