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StashRaid

Storage Parameters

Usable Capacity

12 TB

Fault Tolerance

4

Array Resilience

Architecture

RAID 5 • Parity

Fault Tolerance

1 Concurrent Failures Allowed

Current Configuration

RAID 5 (Parity)

12 TB Usable

Total RAW: 16 TB

Disk 01DATA
Disk 02DATA
Disk 03DATA
Disk 04PARITY

Total Drives

4 x 4 TB

Efficiency

75% Utilized

Usable: 12 TBWasted to redundancy: 4 TB

Pros & Cons

  • PRO: Good balance of capacity/speed/safety

  • PRO: Cost-effective redundancy

  • CON: Slower writes due to parity calculation

    This setup prioritizes redundancy but has associated performance or capacity costs.

RAID 5 Calculator

Use the RAID 5 calculator above to see how much usable space you'll get when pooling drives with single-parity redundancy.

How RAID 5 Capacity Works

RAID 5 stripes data and parity information across all drives. Because the parity calculation is distributed, exactly one drive's worth of capacity is lost to structural overhead. The formula is simply: (Number of Drives - 1) × Size of Smallest Drive.

How Much Space RAID 5 Uses for Parity

No matter how many drives you add to the array, RAID 5 only uses the equivalent of one single drive for parity. However, the more drives you add, the slower a rebuild becomes if a failure occurs.

When RAID 5 Makes Sense

RAID 5 is perfect for small arrays (3-5 drives) or when using SSDs where rebuild times are fast. It provides a great balance of storage space without sacrificing complete redundancy. Want more safety? Compare RAID 5 vs RAID 6 or view our full comparison guide.

RAID 5 FAQ

How much space do I lose in RAID 5?

You lose exactly one drive's capacity. If you have 4x 10TB drives, you lose 10TB to parity, giving you roughly 30TB raw (or ~27TB usable).

What happens when a drive fails?

The array enters a "degraded" state but your data is still accessible. You must replace the broken drive immediately and wait for the array to rebuild before you are safe again.