What Subnet Calculator helps you do

Enter an IPv4 address and CIDR prefix to calculate network address, broadcast, subnet mask, wildcard mask, host range, and usable host count. Built for planning and troubleshooting — not for live network configuration without verifying against your design standard.

Addresses you type are processed locally in your browser and are not sent to Haivix servers.

How it works

Haivix parses dotted-decimal IPv4, validates octets, applies the CIDR mask, and derives network/broadcast boundaries. /31 and /32 follow common IPv4 conventions shown in the results panel.

How to use Subnet Calculator

Enter an address in CIDR form such as 192.168.10.10/24 (prefix defaults to /24 when omitted in some inputs — confirm the prefix field).
Read network, mask, first/last host, total addresses, and usable hosts from the results.
Copy values into your IP plan or ticket, then validate against VLSM design, reserved addresses, and gateway placement.

When to use it

Planning lab or office subnet splits before deployment
Explaining CIDR boundaries during troubleshooting or study
Checking whether an address falls in a private RFC 1918 range

When not to use it

IPv6 planning (use an IPv6-specific tool)
Authoritative IPAM or DHCP configuration without change control
Determining effective policy routes or ACL hit counts in production

Example

192.168.1.10/24 yields network 192.168.1.0, broadcast 192.168.1.255, usable hosts 192.168.1.1–192.168.1.254 (254 usable addresses).

What to know before you start

IPv4 only; no VLSM planner across multiple subnets in one view.
Private/public scope is a heuristic label, not a routing policy decision.
Calculations happen locally but do not ping or validate live address usage.

Common mistakes

Forgetting that network and broadcast addresses are not usable on typical LAN subnets
Mixing up wildcard mask with subnet mask when writing ACLs
Applying /31 semantics from one vendor document without checking your platform

Subnet Calculator