Technology & Computing
vCPU to pCPU Oversubscription Ratio Calculator
Calculate the virtual-to-physical CPU oversubscription ratio for a virtualization or cloud host.
Your inputs
Change any value to update the result instantly.
Oversubscription ratio
12.5 :1
Total vCPUs allocated
800
Physical cores
64
VMs on host
200
Max VMs at 4:1 ratio
64
Typical safe ratios: 3:1–5:1 for general workloads, closer to 1:1 for CPU-intensive apps.
Formula and working
Oversubscription ratio = total allocated vCPUs ÷ physical CPU cores
- 1
Collect the inputs
Physical CPU cores per host = 64 cores; vCPUs allocated per VM = 4 vCPU; Number of VMs on host = 200
- 2
Apply the formula
Oversubscription ratio = total allocated vCPUs ÷ physical CPU cores
- 3
Result
Oversubscription ratio = 12.5 :1
Frequently asked questions
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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