IPv4 Subnet Calculator

Convert an IPv4 address and CIDR prefix into network, broadcast, mask, wildcard and usable-host ranges.

richie woods

A practical IPv4 addressing aid for GCS, payload, sensor and edge-network planning.

Local calculation: values are processed in your browser and are not transmitted. Optional profiles are stored only in this browser.
Active profile: Manual values
/bits

Planning output only. Verify assumptions and results against authoritative data, manufacturer information, approved procedures, test evidence and competent engineering or regulatory review before use.

Calculation basis

The IPv4 address is converted to a 32-bit integer. The CIDR prefix creates the subnet mask; bitwise AND gives the network address and the inverse mask gives the broadcast address. /31 and /32 networks are reported using point-to-point and host-route conventions.

Limitations and verification

  • Does not discover devices, test reachability, configure routes, check VLANs or validate an operational network design.
  • Usable-host conventions can vary for specialist implementations.
  • Avoid publishing operational addressing schemes or sensitive network details.

Version and review status

Formula set: v1.2
Staging review date: 17 August 2026
Status: Staging beta pending user acceptance and cross-browser checks.