/16 vs /24 — Subnet Comparison
A /16 subnet is 256× larger than a /24. Every additional bit in the prefix halves the address space — the 8-bit difference between these two means /16 has 28 = 256 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
254 usable hosts — the industry standard
Typical Uses
- →Home and SOHO LAN (192.168.1.0/24)
- →Standard office VLAN
- →AWS/Azure subnet per AZ
Key Differences
How 256 /24 Subnets Divide a /16
Example using 10.0.0.0/16 as the parent block.
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 10.0.0.0/24 | 10.0.0.0 | 10.0.0.1 | 10.0.0.254 | 10.0.0.255 | 254 |
| 2 | 10.0.1.0/24 | 10.0.1.0 | 10.0.1.1 | 10.0.1.254 | 10.0.1.255 | 254 |
| 3 | 10.0.2.0/24 | 10.0.2.0 | 10.0.2.1 | 10.0.2.254 | 10.0.2.255 | 254 |
| 4 | 10.0.3.0/24 | 10.0.3.0 | 10.0.3.1 | 10.0.3.254 | 10.0.3.255 | 254 |
| 5 | 10.0.4.0/24 | 10.0.4.0 | 10.0.4.1 | 10.0.4.254 | 10.0.4.255 | 254 |
| 6 | 10.0.5.0/24 | 10.0.5.0 | 10.0.5.1 | 10.0.5.254 | 10.0.5.255 | 254 |
| 7 | 10.0.6.0/24 | 10.0.6.0 | 10.0.6.1 | 10.0.6.254 | 10.0.6.255 | 254 |
| 8 | 10.0.7.0/24 | 10.0.7.0 | 10.0.7.1 | 10.0.7.254 | 10.0.7.255 | 254 |
| 9 | 10.0.8.0/24 | 10.0.8.0 | 10.0.8.1 | 10.0.8.254 | 10.0.8.255 | 254 |
| 10 | 10.0.9.0/24 | 10.0.9.0 | 10.0.9.1 | 10.0.9.254 | 10.0.9.255 | 254 |
| 11 | 10.0.10.0/24 | 10.0.10.0 | 10.0.10.1 | 10.0.10.254 | 10.0.10.255 | 254 |
| 12 | 10.0.11.0/24 | 10.0.11.0 | 10.0.11.1 | 10.0.11.254 | 10.0.11.255 | 254 |
| 13 | 10.0.12.0/24 | 10.0.12.0 | 10.0.12.1 | 10.0.12.254 | 10.0.12.255 | 254 |
| 14 | 10.0.13.0/24 | 10.0.13.0 | 10.0.13.1 | 10.0.13.254 | 10.0.13.255 | 254 |
| 15 | 10.0.14.0/24 | 10.0.14.0 | 10.0.14.1 | 10.0.14.254 | 10.0.14.255 | 254 |
| 16 | 10.0.15.0/24 | 10.0.15.0 | 10.0.15.1 | 10.0.15.254 | 10.0.15.255 | 254 |
| … 240 more /24 subnets … | ||||||
FAQ
What is the difference between /16 and /24?
A /16 has 65,534 usable hosts
and a /24 has 254.
The subnet masks differ: /16 uses 255.255.0.0
while /24 uses 255.255.255.0.
Every additional bit in the prefix halves the number of addresses — so the 8-bit gap means
/16 is exactly 256× larger.
How many /24 subnets fit in a /16?
Exactly 256 /24 subnets fit perfectly inside one /16 with no wasted space. To split a /16 into /24s, just increment the last 8 bits of the network address for each new subnet.
Which should I choose?
/16 is typically used for: Cloud VPC CIDR, campus network. /24 is better for: Standard subnet — home, office, cloud. Choose the smallest prefix that comfortably fits your host count — over-allocating wastes address space, but under-allocating means painful renumbering later.