Short answer: Proxmox VE (Virtual Environment) is a free, open-source hypervisor platform for Linux: a Debian-based host OS with a web UI on top that manages KVM virtual machines and LXC containers, clustering, storage and backups from one place. It is what many VPS and dedicated-server providers run on their own hardware to carve it into customer VMs — you can also run it yourself on a dedicated server or at home, which is the common reason people ask what it actually is.
What Proxmox VE actually is
Proxmox VE installs directly onto physical hardware (Proxmox calls this installing onto “bare metal”) as its own Debian-based operating system, and everything else — virtual machines, containers, storage pools, backups, networking — is managed afterward through a web interface on port 8006, a CLI, or its REST API. It bundles two virtualization technologies rather than one:
- KVM (Kernel-based Virtual Machine) for full virtual machines: each one gets its own virtualized CPU, memory, disk and network devices, runs any guest OS (Linux, Windows, BSD), and is isolated from the host at the hardware level.
- LXC for lightweight containers that share the host’s kernel but otherwise behave like a small Linux VM — faster to start, less overhead, Linux guests only. See LXC vs Docker for how that compares to Docker’s very different container model.
Both run side by side on the same host, picked per workload: a Windows VM needs KVM, a small Debian service might run fine and faster as LXC.
Is Proxmox free?
Yes. Proxmox VE itself is free and open source (AGPLv3) with no feature gate and no VM count limit — everything in the web UI works without a subscription. What costs money is the Enterprise Repository, a more conservatively tested package feed, and commercial support; without a subscription, Proxmox nags about this at login and you instead use the No-Subscription repository, which gets the same updates slightly sooner and is what the large majority of self-hosted, single-admin installs run on.
Why run Proxmox instead of plain KVM or libvirt?
| Proxmox VE | Plain KVM + libvirt/virt-manager | |
|---|---|---|
| Setup | Installer builds the whole host OS for you | Install Linux yourself, then KVM, libvirt and a UI separately |
| Management | Web UI, CLI (qm, pct), REST API | virsh CLI, virt-manager (local GUI, not built for remote web use) |
| Containers (LXC) | Built in, same UI as VMs | Separate tooling (lxc-* commands) with no shared interface |
| Clustering | Built in: pool several hosts, migrate VMs live between them | Possible, but you assemble it yourself |
| Storage | ZFS, Ceph, LVM-thin, NFS — configured through the UI | Whatever libvirt supports, configured by hand |
| Backups | Built-in scheduler, incremental, to local or remote storage | Your own scripts, typically around virsh and qemu-img |
| Cost | Free; paid support optional | Free |
Proxmox is essentially the operational layer people end up building around plain KVM anyway — clustering, a web UI, backup scheduling, storage management — packaged and maintained as one product, which is why it is the default choice for anyone running more than a couple of VMs on their own hardware rather than assembling the pieces themselves.
Why hosting providers run Proxmox
A VPS provider’s own hypervisor layer rarely shows up to the customer at all — you get a KVM VM with full virtualization either way, and which management platform the provider runs underneath it is mostly invisible day to day. Proxmox is a common choice on the provider side specifically because of the clustering and live migration: a host can be drained and rebooted for maintenance by moving its VMs elsewhere first, with no downtime for the VMs themselves, and the same web UI scales from one server to a rack of them.
PVE vs PBS vs PMG: three different products
Proxmox the company ships three separate products that share only a naming convention:
- Proxmox VE (this article): the hypervisor platform.
- Proxmox Backup Server (PBS): a separate, dedicated backup target with deduplication and incremental backups, that PVE backs up to — not required to use PVE at all, but commonly paired with it.
- Proxmox Mail Gateway (PMG): an unrelated email spam/virus filtering appliance, also built on Debian, with no functional connection to PVE besides the vendor.
Running Proxmox yourself
Proxmox VE needs real hardware to install onto, or at minimum a hypervisor that itself permits nested virtualization — it is not something you run inside an already virtualized VPS in any useful way, since the whole point is managing hardware virtualization directly. The practical place to run it yourself is a dedicated server: install Proxmox as the host OS, then create your own KVM VMs and LXC containers on top, each isolated from the others exactly the way a hosting provider’s customer VMs are isolated from each other.
| Resource | Workable minimum | Why |
|---|---|---|
| CPU | A CPU with virtualization extensions (Intel VT-x or AMD-V) | KVM will not start a VM without it |
| RAM | 8 GB for a couple of small VMs; realistically 16 GB+ | Each VM reserves memory on top of what Proxmox itself uses |
| Storage | An SSD; ZFS wants more RAM for its own cache | VM disk I/O is the most common bottleneck on a busy host |
| Network | One NIC is enough to start; two if you want to separate management traffic | Clustering and storage replication want their own interface on a serious setup |
Proxmox vs other hypervisor platforms
The other names that come up in the same breath are VMware (ESXi/vSphere, now Broadcom, increasingly licensed for larger deployments only since the 2023 acquisition) and OpenVZ-based panels, which virtualize at the container level only and cannot run Windows guests at all. Proxmox sits between them: full KVM virtualization like VMware, LXC containers like an OpenVZ panel, free and open source like neither.
Frequently asked
Is Proxmox VE free?
Yes, fully — Proxmox VE is open source (AGPLv3) with no feature gate and no VM limit. What costs money is the Enterprise Repository (more conservatively tested updates) and commercial support; without a subscription you use the No-Subscription repository instead, which the large majority of self-managed installs run on.
What is the difference between Proxmox VE, PBS and PMG?
Proxmox VE is the hypervisor platform. Proxmox Backup Server (PBS) is a separate, dedicated backup target with deduplication that PVE can back up to, usable on its own too. Proxmox Mail Gateway (PMG) is an unrelated spam and virus filtering appliance from the same vendor, with no functional connection to PVE.
Does Proxmox use KVM or containers?
Both, side by side, picked per workload: full KVM virtual machines for anything that needs its own kernel or a non-Linux guest such as Windows, and LXC containers for lightweight Linux workloads that share the host kernel and start faster.
Can I run Proxmox on a VPS?
Not usefully — Proxmox needs to manage hardware virtualization directly, which an already-virtualized VPS does not expose. It is built to install onto real hardware, which in practice means a dedicated server if you want to run it yourself rather than renting a VM a provider already created with it.