Do cool things with IP addresses in this Excel sheet. No macros! !!
Features: CALCULATE NETWORK - Given an IP address and CIDR, calculate its individual network SUBNETTING - See relation between the number of Hosts and Networks based on CIDR. FORMAT - Format an IP address so it has 3 digites in each octect. RESERVED IP ADDRESSES AND CLASSES - The amount of reserved space is a little more complicated than what I knew about.