How to Use the VLSM (Variable Length Subnet Mask) Calculator
- Enter your Major Network CIDR (e.g. 192.168.1.0/24 or 10.0.0.0/16).
- Enter required host counts for each department/subnet on separate lines.
- The engine automatically applies VLSM descending rules and generates the complete allocation matrix.
Key Features & Capabilities
- Automatic descending host sort order per official Cisco VLSM rules.
- Itemized allocation table: Network IP, Prefix, Subnet Mask, Usable Range, and Broadcast.
- 100% private client-side computation with zero data logging.
Technical Architecture & Privacy
VLSM (Variable Length Subnet Mask) Calculator is engineered with a focus on performance, mathematical accuracy, and maximum user privacy. Operating entirely in-browser on the client side, all processing takes place locally within your browser's JavaScript engine. None of your financial numbers, text entries, or private inputs are ever transmitted to or stored on remote servers.