Why I Built This
When I was studying networking (and later when I was actually deploying networks for work), the available subnet calculators were either ugly, full of ads, or worse — gave wrong answers on edge cases like /31 and /32 subnets without telling you.
"A tool that doesn't explain itself isn't a tool — it's a black box."
That's the philosophy behind SubnetCalc.io. The calculator is fast because all the math happens in your browser — no server round-trip. But I wanted it to be more than just a number generator. The educational content exists to explain why a /30 has 4 IPs, what a wildcard mask actually represents, and when broadcast addresses do and don't apply.
My day job is building GIS infrastructure and developer tools. SubnetCalc.io is a personal project, built on evenings and weekends, because I genuinely enjoy networking and wanted to contribute something useful to the IT community. It's also, honestly, a project I use myself — I got tired of googling "what's the broadcast address for 10.0.0.0/16" and getting ads in the results.
Background
- GIS & Infrastructure: Several years building systems that ingest, process, and serve large geospatial datasets
- Networking: CCNA-level knowledge applied in real environments — designing small-to-medium network segments, VPNs, cloud VPCs, and container networking (Docker, Kubernetes)
- Writing: Believes that good technical writing explains the "why" alongside the "what"
What the Site Is — and Isn't
SubnetCalc.io is a one-person project. I'm not a big media company, I'm not funded, and I'm not trying to build the next TechCrunch. It's a tool and a blog, maintained by one person who cares about the subject matter.
That also means:
- Content is written and updated by me — not generated or aggregated from third-party feeds
- If you find an error, I want to know about it — email me
- I update articles when networking standards or cloud provider behavior changes
- No investors, no sponsors, no paid placements — just ads to keep the hosting costs covered
Contact
The best way to reach me is by email:
Email: [email protected]
I read every email and do my best to respond. I can't always answer individual networking questions (I have a day job), but I'm genuinely interested in feedback about the site, corrections to articles, and suggestions for new content.
Elsewhere
I occasionally post site updates and networking tips on social media. The best way to reach me is by email at [email protected].