Subnet Finder: A Simple Tool That Makes Networking Easier
Building Subnet Finder with Copilot (AI)
I recently built a small utility called Subnet Finder, using Copilot (AI) to speed up the process. The tool does one simple thing: you enter an IPv4 address, and it instantly tells you its default subnet (like /8, /16, /24) and IP class (A–E).
Why I Built It
When working with networks, I often need to quickly recall default subnets or identify an IP class. Instead of doing it manually each time, I wanted a fast, reliable helper—something lightweight I could reuse.
How Copilot Helped
Copilot assisted with:
Building the logic for checking the IP's first octet
Mapping ranges to the correct class
Returning the right default CIDR
Improving validation and error handling
It saved me time and removed the repetitive parts of coding.
How It Works
Enter any IPv4 address.
The tool reads the first octet.
It returns the IP class and default subnet.
It also flags common private ranges.
Simple, fast, and great for quick network checks.
You can play with it yourself at: https://www.iamtheconzo.com/subnetfinder
