# It's FOSS launches open-source RAID calculator for Linux storage planning

> **Key takeaway:** It's FOSS has released a browser-based, open-source RAID calculator that supports traditional RAID levels, ZFS RAIDZ variants, mixed drive sizes, and power consumption estimates.

**Published:** 2026-10-24T06:13:58+00:00 
**Source:** It's FOSS Community News 
**Category:** distro-news 
**Canonical URL:** https://fosswire.org/news/its-foss-launches-open-source-raid-calculator-for-linux-stor.html 

## Summary
It's FOSS has published a web-based RAID calculator designed for Linux users and system administrators planning storage arrays. The tool covers traditional RAID levels from RAID 0 through RAID 10, as well as ZFS-specific configurations including mirrors, RAIDZ1, RAIDZ2, and RAIDZ3. Users can specify drive counts, capacities in terabytes or gigabytes, and whether all drives match or are mixed sizes. The calculator estimates usable capacity, fault tolerance, storage efficiency, and power draw for four drive types: 3.5-inch HDDs, 2.5-inch HDDs, 2.5-inch SATA SSDs, and NVMe SSDs. It also factors in unrecoverable read error rates by drive class, using manufacturer specifications for consumer versus NAS or enterprise drives. Configurations can be saved and shared via generated links. The tool is implemented as an embeddable web widget with CSS custom properties for theme adaptation.

## What the RAID calculator covers
- **RAID levels supported:** The calculator handles RAID 0 (striping), RAID 1 (mirroring), RAID 5 (single parity), RAID 6 (double parity), RAID 10 (striped mirrors), ZFS mirror, RAIDZ1, RAIDZ2, and RAIDZ3.
- **Drive configuration options:** Users can set the number of drives, choose between uniform or mixed sizes, specify capacity in TB or GB, and select drive class with corresponding URE rates—consumer at 1 in 10¹⁴ bits or NAS/enterprise at 1 in 10¹⁵ bits.
- **ZFS-specific considerations:** The tool notes that real-world ZFS usable space runs 3–8% lower than calculated due to metadata, padding, and pool reservations, and flags this as an upper bound.
- **Power estimation methodology:** Draw estimates use fixed per-drive averages (3.5" HDD at 6.5W, 2.5" HDD at 2.5W, 2.5" SATA SSD at 2.0W, NVMe SSD at 4.0W), multiplied by drive count, with yearly kWh calculated at 24/7 operation—explicitly excluding CPU, motherboard, and PSU overhead.
- **Implementation details:** The widget uses CSS custom properties with `color-mix()` for automatic light/dark theme adaptation, falls back to `rgba()` for older browsers, and supports saving configurations and copying shareable links.

## Why it matters
For Linux administrators and home NAS builders, this tool fills a practical gap by combining traditional mdadm-style RAID and ZFS planning in one interface, with explicit handling of ZFS metadata overhead and URE risks that generic calculators often omit. The open-source implementation and embeddable widget design mean it can be integrated into documentation, forums, or distribution-specific sites, lowering the barrier to informed storage decisions in a community where ZFS adoption continues to grow but expertise remains unevenly distributed.