Enter an IPv4 address with a prefix or subnet mask. You get the network and broadcast addresses, the usable host range, host count, masks, and how the subnet splits into smaller ones. It runs in your browser.
| Subnet | Usable range | Broadcast | Hosts |
|---|
In NetworkSketch, every VLAN area holds its subnet and gateway, and the network check flags any device whose IP falls outside it. Check a whole list at once with the IP plan checker.
Every prefix length with its mask and host counts. /31 is for point-to-point links (both addresses usable) and /32 is a single host.
| Prefix | Subnet mask | Addresses | Usable hosts |
|---|
The first address in a subnet is the network address and the last is the broadcast address; neither can be assigned to a device. The exception is a /31, used on point-to-point links, where both addresses are usable (RFC 3021).
The inverse of the subnet mask (0.0.0.255 for a /24). Cisco ACLs and OSPF network statements use it to say which bits must match.
No. The calculator runs on this page in your browser, and the page has no analytics or tracking. The address you enter is kept in the part of the link after the # so you can share it, and browsers never send that part to the server.