21.64.120.136/29

Public

Class A — /29 prefix — 6 usable hosts

Network Address
21.64.120.136
Broadcast Address
21.64.120.143
Subnet Mask
255.255.255.248
Usable Hosts
6
First Usable IP
21.64.120.137
Last Usable IP
21.64.120.142
Total IPs
8
Prefix Length
/29

Network address — the base address of the block (21.64.120.136). All devices in this subnet share this prefix. Cannot be assigned to a host.

Broadcast address — packets sent to 21.64.120.143 are delivered to every device in the subnet. Also reserved — not assignable.

Usable hosts — the 6 addresses between those two that you can assign to servers, VMs, or interfaces.

Subnet mask255.255.255.248 is the dotted-decimal equivalent of /29. Older tools and Cisco configs use this format instead of CIDR slash notation.

Full Details

CIDR Notation 21.64.120.136/29
Network Address 21.64.120.136
Broadcast Address 21.64.120.143
Subnet Mask 255.255.255.248
Wildcard Mask 0.0.0.7
Prefix Length /29
IP Address Class Class A
Total IP Addresses 8
Usable Host Addresses 6
First Usable IP 21.64.120.137
Last Usable IP 21.64.120.142
Network (Hex) 0x15407888
Broadcast (Hex) 0x1540788F
Address Type Public / Globally Routable

Binary Representation

Network Address
00010101.01000000.01111000 00010101.01000000.01111000.10001000
Subnet Mask
11111111.11111111.11111111.11111000

The first 29 bits (1s in the mask) identify the network. The remaining 3 bits identify hosts within the network.

Split into Equal Subnets

Split 21.64.120.136/29 into 2 equal /30 subnets (2 usable hosts each).

# CIDR Network First Usable Last Usable Broadcast Hosts
1 21.64.120.136/30 21.64.120.136 21.64.120.137 21.64.120.138 21.64.120.139 2
2 21.64.120.140/30 21.64.120.140 21.64.120.141 21.64.120.142 21.64.120.143 2

All 8 IP Addresses in this Range

21.64.120.136 net
21.64.120.137
21.64.120.138
21.64.120.139
21.64.120.140
21.64.120.141
21.64.120.142
21.64.120.143 bcast

/29 Subnet Reference

Total IPs 8
Usable Hosts 6
Subnet Mask 255.255.255.248
Wildcard 0.0.0.7

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