About NetTools

NetTools is a free platform of professional network engineering tools designed for network engineers, students, and IT professionals.

Tools available

• Subnet Calculator — IPv4 CIDR calculator with wildcard masks, broadcast address, and binary representation
• VLSM Planner — Variable Length Subnet Masking planner for optimized IP addressing
• Cisco IOS Script Generator — Generate interface configs, OSPF, ACLs, VLANs, and DHCP ready for the console
• Topology Simulator — Drag-and-drop network design with automatic IP assignment

Philosophy

All tools run entirely in your browser. No login required, no data collected, no registration. Just open the tool and use it.

Open source

NetTools is open source. View the source code at github.com/AnderBarandiaran/nettools.