CIDR / Subnet Calculator
Enter a CIDR block and get network address, broadcast, usable host range, wildcard mask, and subnet size — all computed locally.
The Network Knife for Developers
Network engineering tools that work without a network
Build software without cloud dependencies. The Network Knife gives developers 6 specialised tools in a single HTML file that runs entirely offline.
The Network Knife packages six essential network engineering utilities into a single HTML file. Calculate subnets, plan VLSM allocations, inspect MAC addresses, convert IP addresses to binary, look up HTTP status codes, and reference well-known ports — all without an internet connection. Because the best network tools shouldn't require one.
WHAT'S INSIDE
6 tools in a single HTML file
IP Binary Viewer
Convert IPv4 addresses to binary with colour-coded octets. See exactly which bits belong to the network and which to the host.
MAC Address Inspector
Paste a MAC address and identify the vendor (OUI lookup), format it in common notations, and check if it's unicast, multicast, or locally administered.
VLSM Architect
Plan Variable Length Subnet Mask allocations from a base network. Enter subnet requirements and get an optimised, non-overlapping allocation plan with waste analysis.
HOW IT WORKS
Three steps. No setup.
1
Download the file
Purchase The Network Knife and download a single HTML file. No installer, no account, no setup.
2
Open in any browser
Double-click to open in Chrome, Firefox, Safari, or Edge. Works on any operating system.
3
Start working
Your data stays in your browser's local storage. Nothing is uploaded. Ever.
COMPLIANCE & GEOGRAPHY
Global
Works in any country. No server dependency, no regional restrictions.
FAQ
Frequently Asked Questions
Why should Developers use The Network Knife?
The Network Knife is built for developers who need code & tech tools without cloud dependencies. CIDR calculator, IP binary viewer, MAC inspector, VLSM architect, HTTP status codes, and port reference. The irony: network tools that don't need a network.
Does The Network Knife work offline?
Yes. The Network Knife is a single HTML file that runs entirely in your browser. No internet connection required. Your data never leaves your machine.
Is The Network Knife a subscription?
No. The Network Knife is a one-time purchase ($39). No monthly fees, no renewals, no price increases.
What tools are included in The Network Knife?
The Network Knife includes 6 tools: CIDR / Subnet Calculator, IP Binary Viewer, MAC Address Inspector, VLSM Architect, HTTP Status Code Reference, Port Reference Table. All accessible from a single HTML file.
Can I try The Network Knife before buying?
Yes. Every product page includes an interactive demo you can try in your browser. No signup required.
No cloud One fileOne-time purchase
Get The Network Knife — $39Sovereignty as a Service