CIDR prefix

/27

255.255.255.224

30 usable hosts · 32 addresses

The mask for /27 is 255.255.255.22432 addresses, 30 usable hosts. Small office/VLAN segments.

Mask
255.255.255.224
Wildcard
0.0.0.31
Addresses
32
Hosts
30

Worked example: 192.168.0.0/27

Network address192.168.0.0/27
Broadcast address192.168.0.31
First host192.168.0.1
Last host192.168.0.30

FAQ — /27

What is the subnet mask for /27?

The subnet mask for /27 is 255.255.255.224 (wildcard: 0.0.0.31). The first 27 bits are the network part, the remaining 5 are the host part.

How many hosts fit in a /27?

A /27 block holds 32 addresses, of which 30 are usable hosts (the network and broadcast addresses are excluded).

How many /27 subnets fit in a /24?

A /24 network divides into 8 /27 subnets.

What is a /27 used for?

Small office/VLAN segments.

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