What Is Subnet Calculator?
The Subnet Calculator takes an IPv4 address and CIDR prefix and returns the network address, broadcast address, host range, subnet mask, wildcard mask, usable host count, and IP class. It can also split a subnet into smaller ones.
Who Uses the Subnet Calculator?
Network engineers and IT students use it to plan address space and check a subnet mask at a glance, without memorising every conversion.
How to Use the Subnet Calculator
- Enter an IPv4 address and its prefix length.
- Read the network, broadcast, and usable host range.
- Optionally split the subnet into smaller /26 to /30 pieces.
Why Choose Our Subnet Calculator?
- Wildcard mask included for ACLs
- Flags private, public, and CGNAT ranges
- Subnets a block down into smaller ranges
Try the Subnet Calculator above — it is free, fast, and works on any device. Bookmark this page to return whenever you need it.