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NAS / RAID Calculator
Calculate usable capacity, fault tolerance, and cost per TB for any RAID or ZFS configuration.
2TB500TB
$200$10,000
ZFS — 1 drive failure
ZFS RAIDZ1 Layout
Drives needed
3
Drive size
24TB
Usable capacity
48TB
Raw capacity
72TB
Overhead
33%
Fault tolerance
1 drive
Estimated cost
$2,847
Cost per TB
$59.31/TB
Idle power
~18W
Rebuild risk
~98%
Total cost ($2847) exceeds budget ($2000). Consider fewer drives or smaller capacity.
⚠ ~98% statistical chance of an unrecoverable read error during rebuild (simplified model — scrubbing and enterprise drives reduce real risk). Consider RAIDZ2 / RAID 6 for double-parity protection at this array size.
Recommended drive
WD Red Pro — 24TB NAS HDD
24TB · SATA III 6Gb/s · 3.5" CMR · 7200 RPM · 512MB · $39.542/TB
$949 eachBuy →
RAID protects against drive failure, not ransomware or accidental deletion. Always maintain offsite backups.
FAQ
What RAID levels are supported?
RAID 1, 5, 6, and ZFS RAIDZ1/RAIDZ2/RAIDZ3. We recommend ZFS RAIDZ1 or RAIDZ2 for new builds.
Does RAID replace backups?
No. RAID protects against drive failure, not accidental deletion, ransomware, or site-level disasters. Always maintain offsite backups.
Which RAID level should I choose?
RAIDZ1 for home NAS with 3-6 drives. RAIDZ2 for larger arrays or critical data. RAID 6 for compatibility with non-ZFS systems.