58.210.40.0/21

Public

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

Network Address
58.210.40.0
Broadcast Address
58.210.47.255
Subnet Mask
255.255.248.0
Usable Hosts
2,046
First Usable IP
58.210.40.1
Last Usable IP
58.210.47.254
Total IPs
2,048
Prefix Length
/21

Network address — the base address of the block (58.210.40.0). All devices in this subnet share this prefix. Cannot be assigned to a host.

Broadcast address — packets sent to 58.210.47.255 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 58.210.40.0/21
Network Address 58.210.40.0
Broadcast Address 58.210.47.255
Subnet Mask 255.255.248.0
Wildcard Mask 0.0.7.255
Prefix Length /21
IP Address Class Class A
Total IP Addresses 2,048
Usable Host Addresses 2,046
First Usable IP 58.210.40.1
Last Usable IP 58.210.47.254
Network (Hex) 0x3AD22800
Broadcast (Hex) 0x3AD22FFF
Address Type Public / Globally Routable

Binary Representation

Network Address
00111010.11010010 00111010.11010010.00101000.00000000
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.

Split into Equal Subnets

Split 58.210.40.0/21 into 2 equal /22 subnets (1,022 usable hosts each).

# CIDR Network First Usable Last Usable Broadcast Hosts
1 58.210.40.0/22 58.210.40.0 58.210.40.1 58.210.43.254 58.210.43.255 1,022
2 58.210.44.0/22 58.210.44.0 58.210.44.1 58.210.47.254 58.210.47.255 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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