WintelGuy.com
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:

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

Hypervisor host specification:

# of CPUs
Cores per CPU
CPU speed (GHz)
Hyper-threading
RAM (GB)
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

The Get Link button generates a URL for this page with all currently entered data and then shortens it using the Google URL Shortener service goo.gl. If you save or bookmark the short link, you can return to your calculation at a later time.

Note that, as stated by Google, "All goo.gl URLs and click analytics are public and can be accessed by anyone" - so use at your discretion.