How Many Windows Server Standard Licenses Do I Need for My ESXi Setup?

You might want to check out the unofficial Windows licensing calculator; it could help clarify things. Generally speaking, when you hit about 80-90% of your core limit, it might be time to consider switching to Datacenter for better value. If you're planning on deploying more VMs in the future, Datacenter could be the way to go.

If you're just running these VMs on a single host, stacking Standard licenses is fine. But if you end up clustering multiple hosts, remember that each host needs licensing for all potential VMs. That’s when it can get confusing, and Datacenter might just be the easier, cost-effective solution.

You’ll need to purchase 5 licenses to cover the 80 physical cores on your server since each Windows Server Standard license covers 16 cores. The vCPU setup for the VMs doesn’t factor into this calculation at all.

Just in case it’s helpful, each Standard license allows two OS environments (VMs) per license, so you'd need enough to cover your total cores. Keep an eye on your future plans because Datacenter may be cheaper if you want to run many more VMs.