A /27 has 32 addresses, 30 usable, mask 255.255.255.224. Blocks start every 32 addresses: .0, .32, .64 and so on. It fits small segments such as a server rack, a set of printers or a small office, and it’s a frequent answer in VLSM exercises that ask for about 25 hosts.
Facts
- Prefix
- /27
- Subnet mask
- 255.255.255.224
- Wildcard mask
- 0.0.0.31
- Binary mask
- 11111111.11111111.11111111.11100000
- Total addresses
- 32
- Usable hosts
- 30
- Example range
- 192.168.1.0/27: 192.168.1.0 – 192.168.1.31
- Typical use
- Small network segments.
Try it
Try: , ,
- CIDR block
- 192.168.1.0/27
- IP range
- 192.168.1.0 – 192.168.1.31
- Addresses
- 32
- Usable hosts
- 30
- Subnet mask
- 255.255.255.224
- Wildcard mask
- 0.0.0.31
Frequently asked questions
How many hosts are in a /27?
A /27 has 32 addresses. Subtracting the network and broadcast addresses leaves 30 usable hosts.
What is the subnet mask for /27?
/27 is 255.255.255.224 (wildcard mask 0.0.0.31). In binary that’s 27 ones followed by 5 zeros.