87.2.0.0/20

Public

Class A — /20 prefix — 4,094 usable hosts

Network Address
87.2.0.0
Broadcast Address
87.2.15.255
Subnet Mask
255.255.240.0
Usable Hosts
4,094
First Usable IP
87.2.0.1
Last Usable IP
87.2.15.254
Total IPs
4,096
Prefix Length
/20

Network address — the base address of the block (87.2.0.0). All devices in this subnet share this prefix. Cannot be assigned to a host.

Broadcast address — packets sent to 87.2.15.255 are delivered to every device in the subnet. Also reserved — not assignable.

Usable hosts — the 4,094 addresses between those two that you can assign to servers, VMs, or interfaces.

Subnet mask255.255.240.0 is the dotted-decimal equivalent of /20. Older tools and Cisco configs use this format instead of CIDR slash notation.

Full Details

CIDR Notation 87.2.0.0/20
Network Address 87.2.0.0
Broadcast Address 87.2.15.255
Subnet Mask 255.255.240.0
Wildcard Mask 0.0.15.255
Prefix Length /20
IP Address Class Class A
Total IP Addresses 4,096
Usable Host Addresses 4,094
First Usable IP 87.2.0.1
Last Usable IP 87.2.15.254
Network (Hex) 0x57020000
Broadcast (Hex) 0x57020FFF
Address Type Public / Globally Routable

Binary Representation

Network Address
01010111.00000010 01010111.00000010.00000000.00000000
Subnet Mask
11111111.11111111.11110000.00000000

The first 20 bits (1s in the mask) identify the network. The remaining 12 bits identify hosts within the network.

Split into Equal Subnets

Split 87.2.0.0/20 into 2 equal /21 subnets (2,046 usable hosts each).

# CIDR Network First Usable Last Usable Broadcast Hosts
1 87.2.0.0/21 87.2.0.0 87.2.0.1 87.2.7.254 87.2.7.255 2,046
2 87.2.8.0/21 87.2.8.0 87.2.8.1 87.2.15.254 87.2.15.255 2,046

/20 Subnet Reference

Total IPs 4,096
Usable Hosts 4,094
Subnet Mask 255.255.240.0
Wildcard 0.0.15.255

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