RAID 60 Calculator
RAID 60 stripes data across two or more RAID 6 groups. Each group gives two drives to parity and survives two failures of its own, which suits large arrays of high-capacity drives.
RAID 60 at a glance
- 14 × 24TB in RAID 60 = 240TB usable (218.28 TiB), 71% of raw capacity; survives at least 2 drive failures, up to 4 if each is in a different group.
- 200TB usable from 24TB drives in RAID 60 takes 14 drives (240TB usable).
Identical drives; decimal TB as drives are sold, binary TiB as most operating systems show it; before filesystem overhead. Hot spares are extra drives and add no capacity.
RAID 60 usable capacity by drive count
| Drives | 1.92TB | 3.84TB | 8TB | 12TB | 16TB | 24TB |
|---|---|---|---|---|---|---|
| 8 (2 groups) | 7.68TB | 15.36TB | 32TB | 48TB | 64TB | 96TB |
| 10 (2 groups) | 11.52TB | 23.04TB | 48TB | 72TB | 96TB | 144TB |
| 12 (2 groups) | 15.36TB | 30.72TB | 64TB | 96TB | 128TB | 192TB |
| 16 (2 groups) | 23.04TB | 46.08TB | 96TB | 144TB | 192TB | 288TB |
| 20 (2 groups) | 30.72TB | 61.44TB | 128TB | 192TB | 256TB | 384TB |
| 24 (2 groups) | 38.4TB | 76.8TB | 160TB | 240TB | 320TB | 480TB |
Usable capacity in decimal TB, before filesystem overhead. — means the drive count is not valid for RAID 60.
RAID 60 formula
Usable capacity = (n − 2g) × S, where g is the number of RAID 6 groups (at least 2, each with at least 4 drives and the same drive count). Minimum 8 drives. Example: 24 × 20TB in 2 groups = 400TB (363.8 TiB).
Fault tolerance
Two drives per group are guaranteed: the array survives any 2 failures, and up to 2 × g if they are spread across groups. Three failures in the same group lose the array.
When to choose RAID 60
Large shelves of nearline drives for backup, archive and video, where one RAID 6 group would be too wide to rebuild quickly. Splitting into groups keeps each rebuild smaller.
24TB drives for this array
In-stock 24TB drives from our catalogue, with the price for the 14 drives in the example above. Hot spares are extra.
- Western 0F62798 Western Digital 0F62798 Ultrastar DC HC580 24TB 7200RPM 6Gb/s SATA 512e $960.00 each · 14 drives $13,440.00
- Seagate ST24000NM007H Exos X24 24TB 7200RPM 12Gb/s SAS 512MB Cache 512e 3.5-Inch Hard $1,450.00 each · 14 drives $20,300.00
- Western WUH722424ALE604 Western Digital WUH722424ALE604 Ultrastar DC HC580 24TB 7200RPM $960.00 each · 14 drives $13,440.00
- Dell GPP63 Dell 0GPP63 / GPP63 24TB 7200RPM 12Gb/s SAS 512MB Cache 512e Hot-Pluggable $1,589.47 each · 14 drives $22,252.58
- Western WD240EDGZ Western Digital WD240EDGZ 24TB 7200RPM SATA 6Gb/s 3.5-inch Internal $960.00 each · 14 drives $13,440.00
- 400-BRRZ - Dell 24TB SAS 12Gb/s 7.2K 512e 3.5-inch LFF Brand New Hard Drive for PowerEdge $1,950.00 each · 14 drives $27,300.00
- Seagate ST24000NM000H Exos X24 24TB SATA 6Gb/s 3.5-Inch Hard Drive $987.37 each · 14 drives $13,823.18
- Western 0F62835 Western Digital 0F62835 Ultrastar DC HC580 24TB 7200RPM 12Gb/s SAS 512MB $2,068.42 each · 14 drives $28,957.88
Frequently asked questions
How many 24TB drives do I need for 200TB usable in RAID 60?
14 drives in 2 groups of 7: 240TB usable (218.28 TiB), before filesystem overhead. The same target takes 11 drives in a single RAID 6 group.
What is the usable capacity of 24 × 20TB drives in RAID 60?
400TB with 2 groups of 12: 20 drives of data, 4 of parity.
What is the minimum number of drives for RAID 60?
Eight: two RAID 6 groups of four drives each.
How many drives can fail in RAID 60?
At least two, and up to two per RAID 6 group, as long as no group loses three drives.
RAID calculators by level
- RAID calculator (all levels)
- RAID 0 calculator
- RAID 1 calculator
- RAID 5 calculator
- RAID 6 calculator
- RAID 10 calculator
- RAID 50 calculator
RAID planning guides
- How Many Drives Can Fail in Each RAID Level?
- RAID Hot Spare: What It Does and How It Affects Capacity
- TB vs TiB: Why a 24TB Drive Shows 21.8 TiB
- RAID Write Penalty by Level
- Best RAID Level for 2, 3, 4, 5, 6 or 8 Drives
- RAID 50 vs RAID 60
- RAID 6 vs RAID 60
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Updated 2026-10-22.