203.10.13.0/25

Public

Class C — /25 prefix — 126 usable hosts

Network Address
203.10.13.0
Broadcast Address
203.10.13.127
Subnet Mask
255.255.255.128
Usable Hosts
126
First Usable IP
203.10.13.1
Last Usable IP
203.10.13.126
Total IPs
128
Prefix Length
/25

Network address — the base address of the block (203.10.13.0). All devices in this subnet share this prefix. Cannot be assigned to a host.

Broadcast address — packets sent to 203.10.13.127 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 203.10.13.0/25
Network Address 203.10.13.0
Broadcast Address 203.10.13.127
Subnet Mask 255.255.255.128
Wildcard Mask 0.0.0.127
Prefix Length /25
IP Address Class Class C
Total IP Addresses 128
Usable Host Addresses 126
First Usable IP 203.10.13.1
Last Usable IP 203.10.13.126
Network (Hex) 0xCB0A0D00
Broadcast (Hex) 0xCB0A0D7F
Address Type Public / Globally Routable

Binary Representation

Network Address
11001011.00001010.00001101 11001011.00001010.00001101.00000000
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 203.10.13.0/25 into 2 equal /26 subnets (62 usable hosts each).

# CIDR Network First Usable Last Usable Broadcast Hosts
1 203.10.13.0/26 203.10.13.0 203.10.13.1 203.10.13.62 203.10.13.63 62
2 203.10.13.64/26 203.10.13.64 203.10.13.65 203.10.13.126 203.10.13.127 62

IP Address Sample

Showing first 16 of 128 total IPs.

203.10.13.0 net
203.10.13.1
203.10.13.2
203.10.13.3
203.10.13.4
203.10.13.5
203.10.13.6
203.10.13.7
203.10.13.8
203.10.13.9
203.10.13.10
203.10.13.11
203.10.13.12
203.10.13.13
203.10.13.14
203.10.13.15
… 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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