10.0.1.0/25

Private (RFC 1918) RFC 1918

Class A — /25 prefix — 126 usable hosts

Network Address
10.0.1.0
Broadcast Address
10.0.1.127
Subnet Mask
255.255.255.128
Usable Hosts
126
First Usable IP
10.0.1.1
Last Usable IP
10.0.1.126
Total IPs
128
Prefix Length
/25

Network address — the base address of the block (10.0.1.0). All devices in this subnet share this prefix. Cannot be assigned to a host.

Broadcast address — packets sent to 10.0.1.127 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 10.0.1.0/25
Network Address 10.0.1.0
Broadcast Address 10.0.1.127
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 10.0.1.1
Last Usable IP 10.0.1.126
Network (Hex) 0x0A000100
Broadcast (Hex) 0x0A00017F
Governing RFC RFC 1918
Address Type Private (RFC 1918)

Binary Representation

Network Address
00001010.00000000.00000001 00001010.00000000.00000001.00000000
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.

Subnet Breakdown — splitting into /26

This /25 block can be divided into 2 /26 subnets.

CIDR Network Broadcast First Usable Last Usable Hosts
10.0.1.0/26 10.0.1.0 10.0.1.63 10.0.1.1 10.0.1.62 62
10.0.1.64/26 10.0.1.64 10.0.1.127 10.0.1.65 10.0.1.126 62

IP Address Sample

Showing first 16 of 128 total IPs.

10.0.1.0 net
10.0.1.1
10.0.1.2
10.0.1.3
10.0.1.4
10.0.1.5
10.0.1.6
10.0.1.7
10.0.1.8
10.0.1.9
10.0.1.10
10.0.1.11
10.0.1.12
10.0.1.13
10.0.1.14
10.0.1.15
… 112 more IPs …

/25 Subnet Reference

Total IPs 128
Usable Hosts 126
Subnet Mask 255.255.255.128
Wildcard 0.0.0.127

Calculate Another