Technology & Computing
IPv6 Subnetting & Prefix Sizer
Estimate how many /48, /56 or /64 subnets fit inside a given IPv6 allocation and vice versa.
Your inputs
Change any value to update the result instantly.
Subnets available
65,536
Bits available for subnetting
16
Host bits per subnet
80
Parent prefix
32
Child prefix
48
Each /64 subnet still has 2^64 host addresses — IPv6 is designed to never be host-address constrained at that size.
Formula and working
Number of subnets = 2^(childPrefix − parentPrefix)
- 1
Collect the inputs
Allocated prefix = 32; Subnet size to allocate = 48
- 2
Apply the formula
Number of subnets = 2^(childPrefix − parentPrefix)
- 3
Result
Subnets available = 65,536
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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