TrueNAS RAID 10 vs RAID 6 Calculator

Compare usable TB, parity, and failure tolerance between RAID 10 and RAID 6 for TrueNAS NAS users.

Comparison Notes

This page compares RAID 10 and RAID 6 on identical hardware assumptions to help homelab builders choose between capacity efficiency and fault tolerance.

Disk size baseline: 8TB drives
Reserve policy: 10% filesystem headroom
Use the interactive tool for exact real-world constraints

Open Interactive Planner →

Storage Capacity Table

Drives	RAID 10	RAID 6	Delta
4x 8TB	14.40 TB	14.40 TB	+0.00 TB
6x 8TB	21.60 TB	28.80 TB	-7.20 TB
8x 8TB	28.80 TB	43.20 TB	-14.40 TB
10x 8TB	36.00 TB	57.60 TB	-21.60 TB
12x 8TB	43.20 TB	72.00 TB	-28.80 TB

TrueNAS / ZFS Planning Notes

TrueNAS and ZFS planners usually care about parity width, scrub cadence, and healthy operating headroom. Capacity is only one part of pool durability.

• Treat RAID-Z2 as a common baseline for medium and large homelab pools.
• Keep meaningful free space to reduce fragmentation pressure under snapshots.
• Plan vdev growth strategy early, since expansion paths affect long-term efficiency.

Brand / Region Glossary

vdev

A virtual device group in ZFS; multiple vdevs form a storage pool.

Scrub

Background integrity scan that verifies checksums and repairs parity mismatches.

RAID-Z Expansion

ZFS feature set and planning topic for growing parity groups safely.

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: QNAP RAID 10 vs RAID 6 Calculator Next: Unraid RAID 10 vs RAID 6 Calculator →

FAQ

Does this comparison include filesystem reserve?

Yes. The comparison table applies a 10% reserve baseline to reflect realistic operating headroom in NAS and homelab environments.

Can two layouts with similar available space still have very different rebuild risk?

Yes. Similar usable TB does not imply similar failure tolerance or rebuild exposure. Capacity and resiliency should be evaluated together.

How should I select between RAID 10 and RAID 6?

Choose based on your risk tolerance, rebuild window, and performance profile. Higher parity usually lowers capacity but improves resilience.

Does RAID 10 rebuild faster than RAID 6?

Rebuild behavior depends on array width, disk size, and workload pressure. This page focuses on capacity and tolerance; benchmark your actual platform before final choice.