121.2.155.0/25
PublicClass A — /25 prefix — 126 usable hosts
Network address — the base address of the block (121.2.155.0). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 121.2.155.127 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 mask — 255.255.255.128 is the dotted-decimal equivalent of /25. Older tools and Cisco configs use this format instead of CIDR slash notation.
Full Details
| CIDR Notation | 121.2.155.0/25 |
| Network Address | 121.2.155.0 |
| Broadcast Address | 121.2.155.127 |
| 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 | 121.2.155.1 |
| Last Usable IP | 121.2.155.126 |
| Network (Hex) | 0x79029B00 |
| Broadcast (Hex) | 0x79029B7F |
| Address Type | Public / Globally Routable |
Binary Representation
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 121.2.155.0/25 into 2 equal /26 subnets (62 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 121.2.155.0/26 | 121.2.155.0 | 121.2.155.1 | 121.2.155.62 | 121.2.155.63 | 62 |
| 2 | 121.2.155.64/26 | 121.2.155.64 | 121.2.155.65 | 121.2.155.126 | 121.2.155.127 | 62 |
Split 121.2.155.0/25 into 4 equal /27 subnets (30 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 121.2.155.0/27 | 121.2.155.0 | 121.2.155.1 | 121.2.155.30 | 121.2.155.31 | 30 |
| 2 | 121.2.155.32/27 | 121.2.155.32 | 121.2.155.33 | 121.2.155.62 | 121.2.155.63 | 30 |
| 3 | 121.2.155.64/27 | 121.2.155.64 | 121.2.155.65 | 121.2.155.94 | 121.2.155.95 | 30 |
| 4 | 121.2.155.96/27 | 121.2.155.96 | 121.2.155.97 | 121.2.155.126 | 121.2.155.127 | 30 |
Split 121.2.155.0/25 into 8 equal /28 subnets (14 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 121.2.155.0/28 | 121.2.155.0 | 121.2.155.1 | 121.2.155.14 | 121.2.155.15 | 14 |
| 2 | 121.2.155.16/28 | 121.2.155.16 | 121.2.155.17 | 121.2.155.30 | 121.2.155.31 | 14 |
| 3 | 121.2.155.32/28 | 121.2.155.32 | 121.2.155.33 | 121.2.155.46 | 121.2.155.47 | 14 |
| 4 | 121.2.155.48/28 | 121.2.155.48 | 121.2.155.49 | 121.2.155.62 | 121.2.155.63 | 14 |
| 5 | 121.2.155.64/28 | 121.2.155.64 | 121.2.155.65 | 121.2.155.78 | 121.2.155.79 | 14 |
| 6 | 121.2.155.80/28 | 121.2.155.80 | 121.2.155.81 | 121.2.155.94 | 121.2.155.95 | 14 |
| 7 | 121.2.155.96/28 | 121.2.155.96 | 121.2.155.97 | 121.2.155.110 | 121.2.155.111 | 14 |
| 8 | 121.2.155.112/28 | 121.2.155.112 | 121.2.155.113 | 121.2.155.126 | 121.2.155.127 | 14 |
Split 121.2.155.0/25 into 16 equal /29 subnets (6 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 121.2.155.0/29 | 121.2.155.0 | 121.2.155.1 | 121.2.155.6 | 121.2.155.7 | 6 |
| 2 | 121.2.155.8/29 | 121.2.155.8 | 121.2.155.9 | 121.2.155.14 | 121.2.155.15 | 6 |
| 3 | 121.2.155.16/29 | 121.2.155.16 | 121.2.155.17 | 121.2.155.22 | 121.2.155.23 | 6 |
| 4 | 121.2.155.24/29 | 121.2.155.24 | 121.2.155.25 | 121.2.155.30 | 121.2.155.31 | 6 |
| 5 | 121.2.155.32/29 | 121.2.155.32 | 121.2.155.33 | 121.2.155.38 | 121.2.155.39 | 6 |
| 6 | 121.2.155.40/29 | 121.2.155.40 | 121.2.155.41 | 121.2.155.46 | 121.2.155.47 | 6 |
| 7 | 121.2.155.48/29 | 121.2.155.48 | 121.2.155.49 | 121.2.155.54 | 121.2.155.55 | 6 |
| 8 | 121.2.155.56/29 | 121.2.155.56 | 121.2.155.57 | 121.2.155.62 | 121.2.155.63 | 6 |
| 9 | 121.2.155.64/29 | 121.2.155.64 | 121.2.155.65 | 121.2.155.70 | 121.2.155.71 | 6 |
| 10 | 121.2.155.72/29 | 121.2.155.72 | 121.2.155.73 | 121.2.155.78 | 121.2.155.79 | 6 |
| 11 | 121.2.155.80/29 | 121.2.155.80 | 121.2.155.81 | 121.2.155.86 | 121.2.155.87 | 6 |
| 12 | 121.2.155.88/29 | 121.2.155.88 | 121.2.155.89 | 121.2.155.94 | 121.2.155.95 | 6 |
| 13 | 121.2.155.96/29 | 121.2.155.96 | 121.2.155.97 | 121.2.155.102 | 121.2.155.103 | 6 |
| 14 | 121.2.155.104/29 | 121.2.155.104 | 121.2.155.105 | 121.2.155.110 | 121.2.155.111 | 6 |
| 15 | 121.2.155.112/29 | 121.2.155.112 | 121.2.155.113 | 121.2.155.118 | 121.2.155.119 | 6 |
| 16 | 121.2.155.120/29 | 121.2.155.120 | 121.2.155.121 | 121.2.155.126 | 121.2.155.127 | 6 |
IP Address Sample
Showing first 16 of 128 total IPs.