TrueNAS SCALE vs Unraid vs OpenMediaVault in 2026

If you are choosing a home NAS operating system in 2026, three names dominate the shortlist: TrueNAS SCALE, Unraid, and OpenMediaVault (OMV). They are not minor variations on the same idea — they make genuinely different trade-offs about the filesystem, how you grow an array, what hardware they want, and what they cost. Picking the right one is mostly about being honest with yourself about which trade-offs you care about.

This guide compares them on the axes that actually decide the choice.

The one-line summary

• TrueNAS SCALE — ZFS-first, the strongest data integrity story, wants more RAM, grows by adding whole vdevs. The “do it properly” choice.
• Unraid — a unique parity-array model that lets you mix drive sizes and add one disk at a time, with a friendly UI and excellent app/VM support. The “flexible and easy” choice. Paid license.
• OpenMediaVault — lightweight Debian-based NAS that runs on almost anything, including very low-spec hardware. Free. The “repurpose old hardware” choice.

Filesystem and data integrity — the biggest split

This is where the three diverge most.

TrueNAS SCALE is built on OpenZFS. That means copy-on-write, end-to-end checksumming, self-healing (it detects and repairs silent corruption from a redundant copy), snapshots, compression, and replication — all native and integrated. For protecting data against bit rot and silent corruption, ZFS is the strongest option of the three by a wide margin.

Unraid uses a custom parity model on top of individual filesystems (historically XFS/BTRFS per drive), with a dedicated parity disk. Notably, Unraid has added ZFS pool support in recent versions, so you can run ZFS pools alongside the classic array — but the signature Unraid array itself is not ZFS and does not give you ZFS’s end-to-end checksumming on the parity-protected array.

OpenMediaVault uses traditional Linux storage — typically mdadm RAID or single disks with ext4/XFS, and ZFS only via a plugin. Out of the box it lacks the checksumming/self-healing that ZFS provides.

If data integrity is your top priority, this axis alone points to TrueNAS SCALE (or ZFS pools under Unraid).

Array expansion and mixing drives

Unraid’s headline feature: you can add one drive at a time and mix drive sizes freely (the only rule is the parity disk must be at least as large as the largest data disk). For a homelab that grows organically — “I’ll add another disk when I fill up” — this is genuinely excellent and is the main reason people choose Unraid.

TrueNAS SCALE historically grows by adding whole vdevs, and within a vdev disks should match capacity. (OpenZFS RAIDZ expansion now allows adding single disks to an existing RAIDZ vdev on current releases, which softens this, but the planning discipline of ZFS pool design still applies — see our pool design guide.) If you want to drop in one mismatched disk casually, ZFS resists you.

OMV with mdadm allows growing arrays with some effort, but it’s less slick than Unraid’s model.

Apps, containers, and VMs

All three can run apps now, which narrows what used to be a big gap.

• Unraid has long had a polished Docker and VM experience with a large Community Applications catalog — historically the easiest of the three for self-hosting.
• TrueNAS SCALE moved to a native Docker app system in the “Electric Eel” generation (replacing the older Kubernetes-based mechanism), so you can deploy catalog apps or paste a Docker Compose file directly. SCALE also runs KVM VMs. See our SCALE apps guide.
• OMV runs Docker via plugins (Portainer/compose), but app management is more DIY than the other two.

For turnkey self-hosting, Unraid and current SCALE are close; OMV is the more hands-on option.

Hardware requirements

• TrueNAS SCALE / ZFS wants RAM — 8 GB is a practical floor, 16 GB+ is comfortable, more if you run apps/VMs. ZFS uses RAM for its ARC read cache. See the TrueNAS hardware guide.
• Unraid is comparatively modest; the parity model doesn’t demand ZFS-level RAM unless you opt into ZFS pools.
• OMV runs on “toaster-class” hardware — it’ll happily live on an old PC or even an SBC with 1-2 GB of RAM. This is its superpower for repurposing.

Cost

• TrueNAS SCALE — free and open source. No license tiers.
• OpenMediaVault — free and open source. No license tiers.
• Unraid — paid license, tiered by device count. Current pricing is a Starter tier (limited device count), an Unleashed tier (unlimited devices), and a Lifetime tier; the non-Lifetime tiers include a year of updates and then charge an optional annual extension fee for continued updates. Confirm current numbers on Unraid’s site before buying, as pricing changes.

Which one for you

Choose TrueNAS SCALE if data integrity matters most, you can give it the RAM, and you’re willing to plan your pool layout up front. It’s the most “enterprise-grade” of the three at home, and it’s free.

Choose Unraid if you value mixing drive sizes and adding disks one at a time, want the friendliest app/VM experience, and don’t mind paying for a license. It trades ZFS’s integrity guarantees (on the classic array) for unmatched flexibility.

Choose OpenMediaVault if you’re reviving old/low-power hardware, want a free lightweight file server, and don’t need ZFS or polished app management. It’s the lean, frugal option.

There’s no universally “best” answer — there’s the one whose trade-offs match your situation. If you’re protecting irreplaceable data and can afford the RAM, SCALE; if you’re building a flexible media box that grows a disk at a time, Unraid; if you’re standing up a cheap file dump on a spare machine, OMV.

Next steps

• TrueNAS SCALE vs CORE in 2026 if you’ve settled on TrueNAS and need to pick the edition.
• ZFS Pool Design: RAIDZ vs Mirrors to plan a SCALE pool before you install.
• The TrueNAS Hardware Guide for sizing RAM and drives.

See also

• Docker homelab tutorials ↗
• mini PC homelab builds ↗