Subnet and CIDR calculator
Normalize a prefix, inspect its address boundaries and copy the result. Calculating a block does not perform an IP lookup.
8.8.8.0/24
Normalized IPv4 network
24 network bits8 host bits
- First address
- 8.8.8.0
- Last address
- 8.8.8.255
- Total addresses
- 256
- Prefix length
- /24
IPv4 host range
- Subnet mask
- 255.255.255.0
- Wildcard mask
- 0.0.0.255
- Usable addresses
- 254
- First usable
- 8.8.8.1
- Last usable
- 8.8.8.254
The usable count excludes the network and broadcast addresses. It describes address space, not reachable hosts.
No published network profile is available for this exact CIDR. The boundary calculation is still valid.
Reading the calculation
The prefix fixes the network bits. The remaining n bits give 2^n addresses. This is the size of the block, not an allocation, announced route or count of active devices.
IPv4 /31 point-to-point links use both addresses; a /32 identifies one address. IPv6 has no broadcast address. Documentation blocks such as 192.0.2.0/24 and 2001:db8::/32 do not imply public routability.