Open Source JavaScript IT Subnet Calculators

teemIP is an open source, web-based IP Address Management (IPAM) and DDI solution built on the iTop framework. It provides comprehensive IP management: IPv4/IPv6 plan management, subnet hierarchy, IP lifecycle, VLAN and DNS/DHCP integration. teemIP is now maintained by the teemIP SAS founding team: Christophe Naud (original creator), Martin de Laval and Quentin Ville. The company is being officially incorporated in July 2026. The project remains open source under AGPL v3. Professional support, integration services and subscriptions: https://www.teemip.com

phpipam is an open-source web IP address management application (IPAM). Its goal is to provide light, modern and useful IP address management. It is php-based application with MySQL database backend, using jQuery libraries, ajax and some HTML5/CSS3 features.

A web browser based calculator written in HTML and JavaScript that will calculate the Variable Length Subnet Masking for your network. Simply enter your CIDR block address/mask and the number of addresses you need in each network, and it does the rest.