IP subnet calculator (CIDR)
Enter something like 192.168.1.10/24, or an address and a mask separately.
| Network address | — |
| Broadcast address | — |
| First host | — |
| Last host | — |
| Usable hosts | — |
| Total addresses | — |
| Subnet mask | — |
| Wildcard mask | — |
| Prefix (CIDR) | — |
| Private range | — |
How to use
- Enter an address with a prefix such as 192.168.1.10/24.
- Or enter the mask separately, such as 255.255.255.0.
- The network range and host count appear in the table.
Questions
Why two fewer usable hosts?
The network and broadcast addresses are excluded. /31 is treated as a point-to-point link using both addresses (RFC 3021), /32 as a single address.
Which ranges are private?
10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16 (RFC 1918).
IPv6?
IPv4 only for now.
Is my input saved or sent?
No. It is processed in your browser only.
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