100.40.39.0/25

Public

Class A — /25 prefix — 126 usable hosts

Network Address
100.40.39.0
Broadcast Address
100.40.39.127
Subnet Mask
255.255.255.128
Usable Hosts
126
First Usable IP
100.40.39.1
Last Usable IP
100.40.39.126
Total IPs
128
Prefix Length
/25

Network address — the base address of the block (100.40.39.0). All devices in this subnet share this prefix. Cannot be assigned to a host.

Broadcast address — packets sent to 100.40.39.127 are delivered to every device in the subnet. Also reserved — not assignable.

Usable hosts — the 126 addresses between those two that you can assign to servers, VMs, or interfaces.

Subnet mask255.255.255.128 is the dotted-decimal equivalent of /25. Older tools and Cisco configs use this format instead of CIDR slash notation.

Full Details

CIDR Notation 100.40.39.0/25
Network Address 100.40.39.0
Broadcast Address 100.40.39.127
Subnet Mask 255.255.255.128
Wildcard Mask 0.0.0.127
Prefix Length /25
IP Address Class Class A
Total IP Addresses 128
Usable Host Addresses 126
First Usable IP 100.40.39.1
Last Usable IP 100.40.39.126
Network (Hex) 0x64282700
Broadcast (Hex) 0x6428277F
Address Type Public / Globally Routable

Binary Representation

Network Address
01100100.00101000.00100111 01100100.00101000.00100111.00000000
Subnet Mask
11111111.11111111.11111111.10000000

The first 25 bits (1s in the mask) identify the network. The remaining 7 bits identify hosts within the network.

Split into Equal Subnets

Split 100.40.39.0/25 into 2 equal /26 subnets (62 usable hosts each).

# CIDR Network First Usable Last Usable Broadcast Hosts
1 100.40.39.0/26 100.40.39.0 100.40.39.1 100.40.39.62 100.40.39.63 62
2 100.40.39.64/26 100.40.39.64 100.40.39.65 100.40.39.126 100.40.39.127 62

IP Address Sample

Showing first 16 of 128 total IPs.

100.40.39.0 net
100.40.39.1
100.40.39.2
100.40.39.3
100.40.39.4
100.40.39.5
100.40.39.6
100.40.39.7
100.40.39.8
100.40.39.9
100.40.39.10
100.40.39.11
100.40.39.12
100.40.39.13
100.40.39.14
100.40.39.15
… 112 more IPs …

/25 Subnet Reference

Total IPs 128
Usable Hosts 126
Subnet Mask 255.255.255.128
Wildcard 0.0.0.127

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