Work out network address, broadcast, host range, and usable hosts from any IPv4 CIDR. See the network and host bits laid out in binary, split a block into smaller subnets, and keep a CIDR cheat sheet on hand.
Invalid CIDR notation. Example: 192.168.1.0/24
Enter an IPv4 address with a prefix length. For example 10.0.0.0/8, 172.16.0.0/12, or 192.168.1.100/26.
Quick Examples
Additional Details
Every IPv4 address is 32 bits. The prefix length decides how many bits are the network portion (orange) and how many are the host portion (blue).
Split this network into equal subnets by choosing a larger prefix. Shows the first 32 subnets.
| # | Network | First Host | Last Host | Broadcast | Hosts |
|---|
Standard IPv4 CIDR reference. Click any row to load that subnet.
| CIDR | Subnet Mask | Usable Hosts | Typical Use |
|---|
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