/16 vs /28 — Subnet Comparison
A /16 subnet is 4,096× larger than a /28. Every additional bit in the prefix halves the address space — the 12-bit difference between these two means /16 has 212 = 4,096 times as many addresses.
65K IPs — standard VPC or site block
Typical Uses
- →AWS / Azure VPC or VNet CIDR
- →Enterprise campus or data centre segment
- →Docker overlay network
14 usable hosts — tiny segment
Typical Uses
- →AWS VPC endpoint subnet
- →NAT gateway dedicated subnet
- →Small server cluster
Key Differences
FAQ
What is the difference between /16 and /28?
A /16 has 65,534 usable hosts
and a /28 has 14.
The subnet masks differ: /16 uses 255.255.0.0
while /28 uses 255.255.255.240.
Every additional bit in the prefix halves the number of addresses — so the 12-bit gap means
/16 is exactly 4,096× larger.
How many /28 subnets fit in a /16?
Exactly 4,096 /28 subnets fit perfectly inside one /16 with no wasted space. To split a /16 into /28s, just increment the last 12 bits of the network address for each new subnet.
Which should I choose?
/16 is typically used for: Cloud VPC CIDR, campus network. /28 is better for: AWS NAT/endpoint dedicated subnet. Choose the smallest prefix that comfortably fits your host count — over-allocating wastes address space, but under-allocating means painful renumbering later.