How many usable hosts does a /24 have?
A /24 has 256 addresses, and 254 are usable hosts. The network and broadcast addresses are reserved, so subtract two from the total.
Subnet Calculator
Enter an IPv4 address with its prefix to get the network, broadcast, mask, wildcard and the range of usable hosts.
Runs in your browser — nothing is uploaded
About the Subnet Calculator
Subnetting divides an IP network into smaller networks. The CIDR prefix, such as /24, says how many leading bits identify the network. The rest identify hosts, so a /24 leaves 8 host bits, or 256 addresses in total.
The calculator shows the network address, which is the first address, and the broadcast address, which is the last. The usable hosts lie between them, because the first and last are reserved for the network and broadcast.
FAQ
Subnet Calculator — frequently asked
What is a wildcard mask?
A wildcard mask is the inverse of the subnet mask. Access control lists in routers use it. For a /24, the subnet mask is 255.255.255.0 and the wildcard mask is 0.0.0.255.
What are /31 and /32 used for?
A /31 is used for point-to-point links between two routers, where both addresses are usable because a broadcast is not needed. A /32 identifies a single host, often for loopback or host routes.
Which addresses are private?
The private ranges are 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. Addresses in these ranges are not routed on the public internet and are used inside homes and offices.
Can I split a network into smaller subnets with this?
Enter the subnet you want to inspect. To plan splits, use the prefix of each target subnet and check that the new ranges fit inside the original network.
Is my network data stored?
No. The calculation runs in your browser and nothing is sent to a server.
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