IPRangeExplorer

51.237.0.0/18

Public

Class A — /18 prefix — 16,382 usable hosts

Network Address
51.237.0.0
Broadcast Address
51.237.63.255
Subnet Mask
255.255.192.0
Usable Hosts
16,382
First Usable IP
51.237.0.1
Last Usable IP
51.237.63.254
Total IPs
16,384
Prefix Length
/18

Network address — the base address of the block (51.237.0.0). All devices in this subnet share this prefix. Cannot be assigned to a host.

Broadcast address — packets sent to 51.237.63.255 are delivered to every device in the subnet. Also reserved — not assignable.

Usable hosts — the 16,382 addresses between those two that you can assign to servers, VMs, or interfaces.

Subnet mask — 255.255.192.0 is the dotted-decimal equivalent of /18. Older tools and Cisco configs use this format instead of CIDR slash notation.

Full Details

CIDR Notation 51.237.0.0/18
Network Address 51.237.0.0
Broadcast Address 51.237.63.255
Subnet Mask 255.255.192.0
Wildcard Mask 0.0.63.255
Prefix Length /18
IP Address Class Class A
Total IP Addresses 16,384
Usable Host Addresses 16,382
First Usable IP 51.237.0.1
Last Usable IP 51.237.63.254
Network (Hex) 0x33ED0000
Broadcast (Hex) 0x33ED3FFF
Address Type Public / Globally Routable

Binary Representation

Network Address
00110011.11101101 00110011.11101101.00000000.00000000
Subnet Mask
11111111.11111111.11000000.00000000

The first 18 bits (1s in the mask) identify the network. The remaining 14 bits identify hosts within the network.

Split into Equal Subnets

Split 51.237.0.0/18 into 2 equal /19 subnets (8,190 usable hosts each).

# CIDR Network First Usable Last Usable Broadcast Hosts
1 51.237.0.0/19 51.237.0.0 51.237.0.1 51.237.31.254 51.237.31.255 8,190
2 51.237.32.0/19 51.237.32.0 51.237.32.1 51.237.63.254 51.237.63.255 8,190

/18 Subnet Reference

Total IPs 16,384
Usable Hosts 16,382
Subnet Mask 255.255.192.0
Wildcard 0.0.63.255
Full /18 reference →

Related Ranges

Parent /17 block 51.237.0.0/17 Sibling /18 block 51.237.64.0/18

Adjacent Prefix Sizes

/16 65,534 hosts /17 32,766 hosts /18 16,382 hosts /19 8,190 hosts /20 4,094 hosts

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