130.176.64.0/21

Public

Class B — /21 prefix — 2,046 usable hosts

Network Address
130.176.64.0
Broadcast Address
130.176.71.255
Subnet Mask
255.255.248.0
Usable Hosts
2,046
First Usable IP
130.176.64.1
Last Usable IP
130.176.71.254
Total IPs
2,048
Prefix Length
/21

Network address — the base address of the block (130.176.64.0). All devices in this subnet share this prefix. Cannot be assigned to a host.

Broadcast address — packets sent to 130.176.71.255 are delivered to every device in the subnet. Also reserved — not assignable.

Usable hosts — the 2,046 addresses between those two that you can assign to servers, VMs, or interfaces.

Subnet mask255.255.248.0 is the dotted-decimal equivalent of /21. Older tools and Cisco configs use this format instead of CIDR slash notation.

Full Details

CIDR Notation 130.176.64.0/21
Network Address 130.176.64.0
Broadcast Address 130.176.71.255
Subnet Mask 255.255.248.0
Wildcard Mask 0.0.7.255
Prefix Length /21
IP Address Class Class B
Total IP Addresses 2,048
Usable Host Addresses 2,046
First Usable IP 130.176.64.1
Last Usable IP 130.176.71.254
Network (Hex) 0x82B04000
Broadcast (Hex) 0x82B047FF
Address Type Public / Globally Routable

Binary Representation

Network Address
10000010.10110000 10000010.10110000.01000000.00000000
Subnet Mask
11111111.11111111.11111000.00000000

The first 21 bits (1s in the mask) identify the network. The remaining 11 bits identify hosts within the network.

Subnet Breakdown — splitting into /22

This /21 block can be divided into 2 /22 subnets.

CIDR Network Broadcast First Usable Last Usable Hosts
130.176.64.0/22 130.176.64.0 130.176.67.255 130.176.64.1 130.176.67.254 1,022
130.176.68.0/22 130.176.68.0 130.176.71.255 130.176.68.1 130.176.71.254 1,022

/21 Subnet Reference

Total IPs 2,048
Usable Hosts 2,046
Subnet Mask 255.255.248.0
Wildcard 0.0.7.255

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