Network math,
solved.
Professional-grade calculators for subnetting, bandwidth planning, PoE budgets, and more. No sign-ups. No tracking. Just tools that work.
Featured Calculators
Subnet Calculator
Divide networks into subnets, calculate IP ranges, broadcast addresses, and available hosts.
Bandwidth Planner
Determine ISP speed requirements based on user count and activity types.
PoE Budget Calculator
Match devices to Power-over-Ethernet switch capacity and plan your power requirements.
Common Questions
Is my network data safe?
Yes, 100%. All calculations run entirely in your browser using JavaScript. Your IP addresses, subnet configurations, and other network data never leave your device. We don't have servers that process your inputs — there's literally nowhere for the data to go. Check your browser's network tab if you want to verify.
How accurate are the calculations?
We base our calculators on IEEE, IETF, and TIA/EIA standards. Unlike tools that only show theoretical maximums, we account for real-world overhead like protocol headers, efficiency losses, and typical usage patterns. Check our methodology page for detailed references on each calculator.
Is this really free? What's the catch?
No catch. No premium tiers, no "contact sales," no sign-up walls. The site is cheap to run (static hosting), and we built it because we needed these tools ourselves. If you find it useful, tell a colleague.
Can I use this for commercial projects?
Absolutely. Use it for client proposals, network designs, capacity planning, whatever you need. The calculators are tools — what you do with the results is up to you. Just remember these are estimates; always validate critical decisions with actual testing.
I found a bug or have a suggestion. How do I report it?
We'd love to hear from you! Head to our contact page and let us know what's wrong or what you'd like to see. We take accuracy seriously and will investigate any reported issues.
Do you support IPv6?
Not yet, but it's on our roadmap. Currently our subnet and IP tools focus on IPv4. We're planning to add IPv6 support in a future update.
Ready to simplify your network math?
Stop wrestling with spreadsheets and manual calculations. Get accurate results in seconds.
Get Started — It's Free