Safety boundary: Use these instructions only for a router or network you own or are authorised to manage. Never enter a router password, Wi-Fi password, SSID, serial number or private network data into Router Portal.
Calculate an IPv4 network
Results will show network, broadcast, range, total and conventional usable hosts.
Outputs
| Output | Meaning |
|---|---|
| Network | Block identifier |
| Broadcast | Last conventional IPv4 address |
| First/last usable | Typical host range |
| Total | 2^(32-prefix) |
| Usable | Convention; /31 and /32 differ |
Examples
192.168.1.0/24 can be split into two aligned /25 blocks. A /30 is a small block; /31 and /32 need special handling.
1/24 network
↓
2Network/host boundary
↓
3First /25
↓
4Second /25
Accuracy and privacy
Validate every octet, prefix 0–32, non-aligned input and reverse ranges. Do not send private IP input to analytics. This tool does not configure a router.
Frequently asked questions
Does it change my router?
No. It only calculates values.
Why is input normalised?
A non-aligned address is converted to its containing network block.
Are usable hosts always total minus two?
No. /31 and /32 are important exceptions.