Server Virtualization Calculator

This tool calculates the number of hosts in a vSphere ESXi cluster based on the planned VM workload and host configuration.

Virtual server / VM specification:

RAM (GB): 
# of VMs: 
RAM (GB): 
# of VMs: 
RAM (GB): 
# of VMs: 
RAM (GB): 
# of VMs: 
RAM (GB): 
# of VMs: 

Hypervisor host specification:

# of CPUs
Cores per CPU
CPU speed (GHz)
Cluster maximum CPU core allocation (%):
Cluster maximum memory allocation (%):
Hypervisor memory overhead per host (GB):
Hypervisor CPU overhead per host (GHz):
Hypervisor memory overhead per VM (GB):

VM Workload:
Total configured vCPUs:60
Total configured memory (GB):320
Total number of VMs:30
Average VM configuration: 
  - number of vCPUs:2
  - Memory (GB):10.6667
Hosts & Cluster: N hostsN+1 hosts
Number of hosts: 23
Total number of physical CPUs or sockets: 46
Total number of physical CPU cores: 3248
Total number of logical processors: 6496
Total cluster CPU capacity (GHz): 76.8115.2
Total hypervisor CPU overhead (GHz): 3.45.1
Total hypervisor CPU overhead (Cores): 1.41672.1250
Cluster CPU capacity available for VMs (GHz): 73.4110.1
Cluster CPU cores available for VMs: 30.583345.875
Configured vCPUs: 6060
Physical CPU core overcommitment ratio: 1.9619 (196.19%) 1.3079 (130.79%)
Average number of configured vCPUs per host: 3020
Total cluster memory capacity (GB): 512768
Total hypervisor memory overhead (GB): 5.27.8
Cluster memory capacity available for VMs (GB):  506.8760.2
Configured VM memory (GB): 320320
Total VM memory overhead (GB): 33
Total memory required for VMs (GB): 323323
Memory overcommitment ratio 0.6314 (63.14%) 0.4209 (42.09%)
Average number of VMs per host: 1510