EU 10x 12TB RAID-Z1 NAS Calculator

Estimate usable TB, parity, and fault tolerance for EU homelab buyers using 10x 12TB in RAID-Z1.

Capacity Snapshot

Raw Capacity

120.00 TB

Usable Capacity

97.20 TB

Fault Tolerance

1 drive

Efficiency

90.0%

ZFS single-parity equivalent of RAID 5; common for smaller homelab pools. This scenario applies a 10% filesystem reserve.

Mode	Usable	Tolerance	Efficiency
RAID 5	97.20 TB	1 drive	90.0%
RAID 6	86.40 TB	2 drives	80.0%
RAID 10	54.00 TB	1 drive per mirror pair*	50.0%
RAID-Z1	97.20 TB	1 drive	90.0%
RAID-Z2	86.40 TB	2 drives	80.0%

EU deployments often place additional emphasis on energy efficiency and predictable lifecycle upgrades, especially for always-on NAS fleets.

• Choose a layout that minimizes emergency rebuild risk under continuous operation.
• Prefer capacity plans that survive one upgrade cycle without pool redesign.

Capacity and reliability strategy across multiple hardware refresh cycles.

Intentional free-space margin to protect performance and snapshot behavior.

This setup can tolerate 1 drive. Real-world survivability depends on mirror placement, rebuild stress, and drive health.

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

For EU homelab buyers, this NAS planning scenario estimates 97.20 TB usable after a 10% reserve from 120.00 TB raw.

For long-lived NAS pools, resiliency first is usually safer. Capacity can be expanded later, while a risky parity choice can force migration sooner.