RAID Calculator
RAID Comparisons
☾
RAIDZ2 vs RAIDZ3 — 8×12 TB
You have 8 drives of 12 TB (96 TB raw) and are deciding between RAIDZ2 (ZFS double parity with checksums) and RAIDZ3 (ZFS triple parity). The table shows what each choice actually gives you.
| Metric | RAIDZ2 | RAIDZ3 |
|---|---|---|
| Usable capacity | 72 TB | 60 TB |
| Redundancy overhead | 24 TB | 36 TB |
| Storage efficiency | 75% | 62% |
| Fault tolerance (drives) | 2 | 3 |
| Minimum drives | 4 | 5 |
RAIDZ2 gives you 12 TB more usable space on this configuration.
RAIDZ3 survives more simultaneous drive failures — with 8 drives of 12 TB, rebuild windows are long, and that margin is what saves the array when a second drive acts up mid-rebuild.
See it live
Open this exact configuration in the calculator and tweak drives, sizes and levels freely.
More comparisons
RAID 5 vs RAID 64× 4 TB · 12 vs 8 TBRAID 5 vs RAID 64× 8 TB · 24 vs 16 TBRAID 5 vs RAID 64× 12 TB · 36 vs 24 TBRAID 5 vs RAID 66× 8 TB · 40 vs 32 TBRAID 5 vs RAID 68× 8 TB · 56 vs 48 TBRAID 5 vs RAID 104× 8 TB · 24 vs 16 TBRAID 6 vs RAID 108× 8 TB · 48 vs 32 TBRAID 6 vs RAID 104× 12 TB · 24 vs 24 TB