Virtual Infrastructure Sizing
Determine how many hosts, CPU cores, memory and storage your virtual environment needs — including N+1 redundancy. All values are calculated live, nothing is stored.
Your virtual environment
Your sizing
Guide value based on a reference host with 32 physical cores and 768 GB usable RAM. Real sizing also accounts for peak loads, NUMA, licensing, storage performance and networking — we're happy to size this together with you.
Sizing virtual environments properly
Undersized means performance problems and risky maintenance — oversized means dead capital. Three figures matter: the vCPU-to-core ratio, memory, and N+1 redundancy.
The calculator transparently shows whether CPU or RAM drives your host count, based on an openly stated reference host. Fine-tuning — peak loads, NUMA, licensing — is something we do together.
Frequently asked questions
What does CPU overcommit mean?
Several vCPUs share one physical core, because VMs rarely run at full load simultaneously. 3:1 to 5:1 is common for mixed workloads; latency-critical systems such as databases are planned more conservatively.
Why N+1 redundancy?
The cluster must survive the loss of one host — during incidents as well as planned maintenance. N+1 keeps one full host's capacity free for that.
How much RAM per host makes sense?
Enough for the VMs of a failed host to fit without swapping. The calculator rounds up to common configuration sizes.