100.80.165.0/27

Public

Class A — /27 prefix — 30 usable hosts

Network Address
100.80.165.0
Broadcast Address
100.80.165.31
Subnet Mask
255.255.255.224
Usable Hosts
30
First Usable IP
100.80.165.1
Last Usable IP
100.80.165.30
Total IPs
32
Prefix Length
/27

Network address — the base address of the block (100.80.165.0). All devices in this subnet share this prefix. Cannot be assigned to a host.

Broadcast address — packets sent to 100.80.165.31 are delivered to every device in the subnet. Also reserved — not assignable.

Usable hosts — the 30 addresses between those two that you can assign to servers, VMs, or interfaces.

Subnet mask255.255.255.224 is the dotted-decimal equivalent of /27. Older tools and Cisco configs use this format instead of CIDR slash notation.

Full Details

CIDR Notation 100.80.165.0/27
Network Address 100.80.165.0
Broadcast Address 100.80.165.31
Subnet Mask 255.255.255.224
Wildcard Mask 0.0.0.31
Prefix Length /27
IP Address Class Class A
Total IP Addresses 32
Usable Host Addresses 30
First Usable IP 100.80.165.1
Last Usable IP 100.80.165.30
Network (Hex) 0x6450A500
Broadcast (Hex) 0x6450A51F
Address Type Public / Globally Routable

Binary Representation

Network Address
01100100.01010000.10100101 01100100.01010000.10100101.00000000
Subnet Mask
11111111.11111111.11111111.11100000

The first 27 bits (1s in the mask) identify the network. The remaining 5 bits identify hosts within the network.

Split into Equal Subnets

Split 100.80.165.0/27 into 2 equal /28 subnets (14 usable hosts each).

# CIDR Network First Usable Last Usable Broadcast Hosts
1 100.80.165.0/28 100.80.165.0 100.80.165.1 100.80.165.14 100.80.165.15 14
2 100.80.165.16/28 100.80.165.16 100.80.165.17 100.80.165.30 100.80.165.31 14

IP Address Sample

Showing first 16 of 32 total IPs.

100.80.165.0 net
100.80.165.1
100.80.165.2
100.80.165.3
100.80.165.4
100.80.165.5
100.80.165.6
100.80.165.7
100.80.165.8
100.80.165.9
100.80.165.10
100.80.165.11
100.80.165.12
100.80.165.13
100.80.165.14
100.80.165.15
… 16 more IPs …

/27 Subnet Reference

Total IPs 32
Usable Hosts 30
Subnet Mask 255.255.255.224
Wildcard 0.0.0.31

Calculate Another