100.64.78.0/27

Public

Class A — /27 prefix — 30 usable hosts

Network Address
100.64.78.0
Broadcast Address
100.64.78.31
Subnet Mask
255.255.255.224
Usable Hosts
30
First Usable IP
100.64.78.1
Last Usable IP
100.64.78.30
Total IPs
32
Prefix Length
/27

Network address — the base address of the block (100.64.78.0). All devices in this subnet share this prefix. Cannot be assigned to a host.

Broadcast address — packets sent to 100.64.78.31 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 100.64.78.0/27
Network Address 100.64.78.0
Broadcast Address 100.64.78.31
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 100.64.78.1
Last Usable IP 100.64.78.30
Network (Hex) 0x64404E00
Broadcast (Hex) 0x64404E1F
Address Type Public / Globally Routable

Binary Representation

Network Address
01100100.01000000.01001110 01100100.01000000.01001110.00000000
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 100.64.78.0/27 into 2 equal /28 subnets (14 usable hosts each).

# CIDR Network First Usable Last Usable Broadcast Hosts
1 100.64.78.0/28 100.64.78.0 100.64.78.1 100.64.78.14 100.64.78.15 14
2 100.64.78.16/28 100.64.78.16 100.64.78.17 100.64.78.30 100.64.78.31 14

IP Address Sample

Showing first 16 of 32 total IPs.

100.64.78.0 net
100.64.78.1
100.64.78.2
100.64.78.3
100.64.78.4
100.64.78.5
100.64.78.6
100.64.78.7
100.64.78.8
100.64.78.9
100.64.78.10
100.64.78.11
100.64.78.12
100.64.78.13
100.64.78.14
100.64.78.15
… 16 more IPs …

/27 Subnet Reference

Total IPs 32
Usable Hosts 30
Subnet Mask 255.255.255.224
Wildcard 0.0.0.31

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