Subnet calculator
Find the network address, mask, broadcast and host range for an IPv4 subnet.
About this calculator
Enter an IPv4 address and a prefix length such as 24. The calculator gives the network address, subnet mask, broadcast address, first and last usable address and the number of hosts.
A /24 has 256 addresses, of which 254 can be given to devices.
Common questions
What is a prefix length?
The number of bits in the network part of the address. /24 means a mask of 255.255.255.0.
Why are two addresses not usable?
The first is the network address and the last is the broadcast address.
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