The Same Company, Two Completely Different Products
You search "best home server OS" and two names keep coming up: CasaOS and ZimaOS. The screenshots look almost identical. The websites point at each other. And yes — both are made by the same company, IceWhale. So which one do you install?
Here's the one-sentence answer: CasaOS is a dashboard you add to an existing Linux computer. ZimaOS is a complete operating system you install on a dedicated machine. They solve the same problem from opposite directions, and picking the wrong one means reinstalling everything later.
The short version:
| CasaOS | ZimaOS | |
|---|---|---|
| What it is | Dashboard on top of Linux | Full NAS operating system |
| Hardware | Any x86 or ARM (Raspberry Pi, old laptop, VPS) | x86-64 PCs only (mini-PC, ZimaBoard) |
| Install | One command, 5 minutes | USB installer, 20 minutes |
| Built-in RAID | No | Yes (0/1/5/6/JBOD) |
| Virtual machines | No | Yes |
| Open source | Fully (MIT) | Partially |
| Best for | Reusing what you have | A dedicated NAS appliance |
If you already know you want the friendly dashboard route, our CasaOS beginner's guide walks through the full setup on an old PC. This article is the decision guide — read it before you commit.
What Is CasaOS?
Think of CasaOS as Android for home servers. On a phone, Android is a friendly app store and home screen wrapped around Linux. CasaOS does the same for a server: you install it on top of an existing Linux system (Debian or Ubuntu recommended, Raspberry Pi OS also works), and suddenly that command-line machine has a polished web dashboard with a one-click app store.
The install is one command:
curl -fsSL https://get.casaos.io | bash
Five minutes later you open http://your-server-ip in a browser and you're done. Under the hood, CasaOS manages Docker for you — you never need to know Docker exists.
What you get:
- An app store with 150+ one-click apps — Jellyfin, Immich, Nextcloud, Pi-hole, Syncthing, and more
- Runs on almost anything — a 2012 laptop, a Raspberry Pi 4, a cloud VPS, anything with Linux and Docker
- Fully open source (MIT license), community-driven, no accounts required
- Docker Compose support for apps outside the store — full control when you want it
What you don't get: any disk management. There's no RAID setup wizard, no built-in redundancy. If you attach three drives and want them to behave like one protected pool, that's entirely on you (usually MergerFS + SnapRAID, the DIY route). CasaOS is an app platform first, a storage appliance second.
Current version as of August 2026 is v0.4.25, and updates come on a slow quarterly cadence. If you want to learn Docker itself before adding a dashboard, that path is always there too.
What Is ZimaOS?
ZimaOS is what happened when IceWhale looked at CasaOS and said: "what if we rebuilt this as a real NAS operating system, not a layer on top of one?" It started from CasaOS's code and became something different: a complete OS you flash onto a computer, like installing Windows — no Linux underneath to set up first.
Installation is the USB-stick flow: download the installer image, write it to an 8 GB USB drive with Balena Etcher, boot the computer from it, and follow the on-screen wizard. The whole thing is point-and-click; there's no terminal at all. (Note: our test hardware for this article was an Ubuntu server and a Raspberry Pi, and ZimaOS requires a spare x86 PC to boot — so the ZimaOS install steps below follow the official docs rather than our own hands-on test.)
What ZimaOS adds over CasaOS:
- Software RAID managed from the GUI — RAID 0/1/5/6 and JBOD pools with a few clicks, the Synology-style experience on your own hardware
- A built-in VM manager for running full virtual machines
- One-click SMB and NFS file sharing so any computer on your network sees your drives
- Modern filesystem support — ZFS, Btrfs, ext4
- Over-the-air updates from the settings page
- A polished dashboard with a Files app, backups, and remote access built in
The trade-offs: it's x86-64 only (no Raspberry Pi, no ARM boards, no 32-bit machines), and it's not fully open source. The free tier covers most home users — 4 drives and 3 users — with an optional paid ZimaOS+ tier on top. Pre-installed on IceWhale's ZimaBoard and ZimaCube hardware, it also runs on generic mini-PCs like an Intel NUC.
Current version as of August 2026 is v1.6.0. One honest caveat: community forums reported some rough edges in the v1.6.0 upgrade (missing USB drives and broken cron jobs on a few systems), so the safe habit is testing major updates before trusting them with your only copy of important data.
Hardware Requirements, Side by Side
The requirements question decides most cases before any other feature matters. Here's what each actually needs:
| Requirement | CasaOS | ZimaOS |
|---|---|---|
| CPU | Any x86 or ARM (Raspberry Pi 3B+ and up) | x86-64 only |
| RAM | 1 GB minimum, 2 GB comfortable | 2 GB minimum, 4 GB+ recommended |
| Storage | Whatever the OS uses — a 16 GB SD card is fine | 16 GB minimum, 32 GB+ recommended |
| Boot mode | BIOS or UEFI | UEFI only (Secure Boot off) |
| OS to start from | Existing Debian/Ubuntu install | Nothing — installs from its own USB |
The CasaOS system requirements are forgiving because it borrows the host system. The ZimaOS system requirements are stricter because it is the system. If your "spare computer" is a Raspberry Pi or a 2011 laptop without UEFI, ZimaOS is simply off the table — and CasaOS becomes the answer by default. If you have a recent mini-PC, both are options and the feature table below decides.
Feature by Feature
| Feature | CasaOS | ZimaOS |
|---|---|---|
| One-click app store | ✅ 150+ apps | ✅ same store, same apps |
| Software RAID in GUI | ❌ DIY only | ✅ 0/1/5/6/JBOD |
| Virtual machines | ❌ | ✅ built-in manager |
| SMB/NFS sharing wizard | ⚠️ manual setup | ✅ one click |
| ARM / Raspberry Pi | ✅ | ❌ |
| Full open source | ✅ MIT | ⚠️ partially |
| Over-the-air updates | ⚠️ rare, manual | ✅ built in |
| Runs on a VPS | ✅ | ❌ (needs bare metal) |
Notice the app store row: both use the same CasaOS App Store, so the apps you can run — Jellyfin for a cheap media server, Nextcloud, Immich, Pi-hole — are identical. The difference is everything around the apps: storage, VMs, sharing, updates.
Which Should You Choose?
Walk through these scenarios and pick the first one that matches:
"I already have Ubuntu/Debian running on this machine." → CasaOS. One command adds the dashboard without touching your existing setup. ZimaOS would wipe it and start over.
"My spare hardware is a Raspberry Pi." → CasaOS. ZimaOS won't boot on ARM, period.
"I have an old laptop in a drawer." → Either works. Choose CasaOS to keep it dual-purpose (it can still be a laptop), or ZimaOS if it's becoming a headless server forever.
"I want two or more drives working as one protected pool." → ZimaOS. The RAID wizard alone justifies it; with CasaOS you'd be hand-editing config files.
"I want to run full virtual machines on it." → ZimaOS.
"I care about pure open source and zero vendor lock-in." → CasaOS. Its MIT license means no one can ever put features behind a paywall.
"I've never used Linux and don't want to." → ZimaOS on a mini-PC gives the most appliance-like experience; CasaOS still requires getting Debian onto the machine first (our old PC home server guide covers that route step by step).
One more consideration: if you want a project to learn on, CasaOS on a repurposed machine teaches you more, because the Linux underneath is right there when you're ready to peek. ZimaOS hides it, which is the point.
Can You Switch Later?
Not with one click. There's no official CasaOS → ZimaOS migration tool — they're different installs with different storage stacks, so switching means reinstalling and setting up your apps again. The good news: your media and documents usually live on separate data drives, and those survive a reinstall either way. The app configuration is what you redo.
Which means the low-regret path is: start with CasaOS (zero cost, works on anything), and if you later hit the RAID/VM wall, move to ZimaOS with your data intact. The reverse is also common — ZimaOS users who want to reclaim an older ARM box switch to CasaOS for that hardware.
FAQ
What are the CasaOS system requirements? Any Linux machine with Docker 20 or newer: 1 GB RAM minimum (Raspberry Pi 3B+ or Pi 4 comfortable), a few GB of disk, x86 or ARM. Debian and Ubuntu are the recommended hosts.
What are the ZimaOS system requirements? An x86-64 PC with UEFI boot (Secure Boot disabled), 2 GB RAM minimum (4 GB or more recommended), 16 GB of storage minimum (32 GB+ recommended). No ARM, no BIOS-only machines.
Can I install ZimaOS on a Raspberry Pi? No. ZimaOS is x86-64 only. Raspberry Pi owners should use CasaOS.
Is ZimaOS free? Yes, with limits — the free tier covers 4 drives and 3 users, which fits most home setups. An optional paid tier (ZimaOS+) removes those limits.
Is CasaOS still maintained in 2026? Yes — v0.4.25 is current, though updates come quarterly rather than monthly. The project is community-driven and the app store keeps growing.
Which is better for a beginner? ZimaOS is the most polished out of the box but demands a specific kind of hardware. CasaOS is simpler to try (one command) and works on anything, but you're expected to bring your own Linux. If you have a mini-PC, go ZimaOS; if you have anything else, go CasaOS.
Does either need a monthly subscription? No. Both are free to install and use for home purposes; only ZimaOS has an optional paid tier, and you can run forever without it.
Next Steps
Now that you've picked a side, here's the path forward:
- Going with CasaOS? Follow the full setup on an old PC — USB stick to app store in under an hour.
- Prefer the traditional route? Turning an old PC into a home server with Ubuntu teaches you the layers CasaOS hides.
- First app either way? A cheap Jellyfin server turns any of this hardware into your own personal Netflix.
- Want access from anywhere? Tailscale gets you into your dashboard from your phone without opening router ports.
- Still not sure self-hosting is for you? See what else you can replace cloud services with — the list might surprise you.
Pick one, start this weekend, and in a month you'll wonder why you paid for cloud storage.
All code in this article was tested and runs successfully on Ubuntu 24.04 with Docker 29.1.3 — verified August 2026. The CasaOS installer script was downloaded and inspected (v0.4.25 frontend), and get.casaos.io responds HTTP 200. ZimaOS install steps are based on the official docs and were not executed on bare metal — no spare x86 hardware was available.