FieldengNetworking & Communications
IPv4 Subnet
Network, broadcast, mask, and usable host range from an IPv4 address and prefix or mask.
Networking & Communications
Network, broadcast, mask, and usable host range from an IPv4 address and prefix or mask.
App id: NET-01. Reference version 1.0.
How to fill it
Fill the inputs. The tool shows the outputs.
On the tool screen, Calc is the working sheet. Presets stores values you reuse. Reference is the formula, assumptions, and provenance below.
Formula
network = address AND mask; hosts = 2^(32−prefix) − 2 (/31 and /32 special-cased)Inputs
| Name | Unit |
|---|---|
| IPv4 address | ipv4 |
| Prefix length (optional) | 1 |
| Subnet mask (optional) | ipv4 |
Outputs
| Name | Unit |
|---|---|
| Network address (hero result) | ipv4 |
| Broadcast address | ipv4 |
| Subnet mask | ipv4 |
| Prefix length | 1 |
| Usable hosts | 1 |
| First usable address | ipv4 |
| Last usable address | ipv4 |
Diagnose
This tool does not attach diagnose observations.
Assumptions
- Provide a prefix length or a dotted-decimal mask. If both are given they must agree.
- /31 and /32 do not subtract network and broadcast from the host count.
Provenance
- IPv4 subnetting. /31 is treated as a point-to-point pair (RFC 3021). /32 is a single host.