RAID Usable Capacity Calculator
Pick the HDD count and size to compare usable capacity for each RAID level.
- Raw capacity
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- Most common (RAID 5)
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Usable Capacity by RAID Level
RAID Levels
- RAID 1Copies the same data to two drives. The safest option, but only 50% capacity efficiency.
- RAID 5Spreads data and parity across drives. Uses one drive's worth for parity and survives one failure.
- RAID 6Dual parity protects data even if two drives fail at once.
- RAID 10Combines RAID 1 and 0 for performance and reliability. Needs an even number of drives, at least 4.