/24 vs /27 — Subnet Comparison
A /24 subnet is 8× larger than a /27. Every additional bit in the prefix halves the address space — the 3-bit difference between these two means /24 has 23 = 8 times as many addresses.
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
30 usable hosts — small workgroup
Typical Uses
- →Small workgroup LAN
- →Network device management subnet
- →Cloud NAT gateway subnet
Key Differences
How 8 /27 Subnets Divide a /24
Example using 10.0.0.0/24 as the parent block.
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 10.0.0.0/27 | 10.0.0.0 | 10.0.0.1 | 10.0.0.30 | 10.0.0.31 | 30 |
| 2 | 10.0.0.32/27 | 10.0.0.32 | 10.0.0.33 | 10.0.0.62 | 10.0.0.63 | 30 |
| 3 | 10.0.0.64/27 | 10.0.0.64 | 10.0.0.65 | 10.0.0.94 | 10.0.0.95 | 30 |
| 4 | 10.0.0.96/27 | 10.0.0.96 | 10.0.0.97 | 10.0.0.126 | 10.0.0.127 | 30 |
| 5 | 10.0.0.128/27 | 10.0.0.128 | 10.0.0.129 | 10.0.0.158 | 10.0.0.159 | 30 |
| 6 | 10.0.0.160/27 | 10.0.0.160 | 10.0.0.161 | 10.0.0.190 | 10.0.0.191 | 30 |
| 7 | 10.0.0.192/27 | 10.0.0.192 | 10.0.0.193 | 10.0.0.222 | 10.0.0.223 | 30 |
| 8 | 10.0.0.224/27 | 10.0.0.224 | 10.0.0.225 | 10.0.0.254 | 10.0.0.255 | 30 |
FAQ
What is the difference between /24 and /27?
A /24 has 254 usable hosts
and a /27 has 30.
The subnet masks differ: /24 uses 255.255.255.0
while /27 uses 255.255.255.224.
Every additional bit in the prefix halves the number of addresses — so the 3-bit gap means
/24 is exactly 8× larger.
How many /27 subnets fit in a /24?
Exactly 8 /27 subnets fit perfectly inside one /24 with no wasted space. To split a /24 into /27s, just increment the last 3 bits of the network address for each new subnet.
Which should I choose?
/24 is typically used for: Standard subnet — home, office, cloud. /27 is better for: Small workgroup / management subnet. Choose the smallest prefix that comfortably fits your host count — over-allocating wastes address space, but under-allocating means painful renumbering later.