RAID capacity estimate

Estimate equal-drive usable capacity for RAID 0, 1, 5, 6 or 10 with optional hot spares.

Tool guide

How to use RAID capacity estimate

Estimate equal-drive usable capacity for RAID 0, 1, 5, 6 or 10 with optional hot spares.

  1. Enter the values and choose the operation or units. Read the supported limits beside the inputs; try the labelled sample to see an example.
  2. RAID is not backup. Equal-size capacity estimate excludes filesystem, formatting and vendor overhead; no speed, recovery or data-protection guarantee.
  3. Choose Estimate RAID capacity. Review the result, then download the text result. Editing inputs invalidates old results.
  4. Calculations are local and unmetered. Inputs and results are not uploaded or saved to your account; leaving the page clears them. Downloaded files remain on your device.
Read the full guide

Common questions

What are the limits of RAID capacity estimate?

2–64 drives. RAID 0/1 need 2 active, 5 needs 3, 6 needs 4, 10 needs even ≥4. Drive size (0,10^6]. RAID is not backup. Equal-size capacity estimate excludes filesystem, formatting and vendor overhead; no speed, recovery or data-protection guarantee.