Python Subnet Calculator

A simple CLI tool to compute network details for IPv4/IPv6 CIDR input.

• Inputs a CIDR (e.g., 192.168.10.0/24 or 2001:db8::/64)
• Outputs: network address, broadcast (v4), first/last usable (v4), total hosts, wildcard mask, and CIDR summary
• Supports bulk mode from a file of prefixes
• Tested with pytest

Quick Start

1. Create and activate a virtual environment

python3 -m venv .venv
source .venv/bin/activate

Re-run the source .venv/bin/activate command whenever you open a new terminal session so the virtual environment stays active.

2. Install dependencies

Choose one of the following approaches:

• Editable install (recommended for development) – installs the package along with dependencies and exposes the subnetcalc console shortcut declared in pyproject.toml:

  python3 -m pip install --editable .

• Requirements file – installs only third-party dependencies, after which you continue running the CLI through python3 -m subnet_calc:

  python3 -m pip install -r requirements.txt

3. Run the CLI

python3 -m subnet_calc --cidr 192.168.1.0/24
python3 -m subnet_calc --file prefixes.txt --summary

If you performed the editable install you can now invoke the shortcut directly:

subnetcalc --cidr 192.168.1.0/24
subnetcalc --file prefixes.txt --summary

4. Execute the test suite (optional)

python3 -m pytest -q