I've seen network administrator at work recently. He was configuring Windows machine in .240 subnet, with address somewhere in the middle of range, and I could virtually see his brains figuring out gateway address, which is usually the first available address of the subnet. I do not know why there were no DHCP, but anyway, this was a good reason to write a calculator.
Subnetting is a technique used to divide a network into smaller subnetworks, providing benefits such as more efficient routing, improved security, and easier management. Our IP address and subnet mask calculator is a tool designed to determine subnet parameters for a given IP address and subnet mask. The calculator calculates the following information: subnet network address, first and last available subnet addresses, subnet broadcast address, and the number of hosts in the subnet. I hope this calculator will be a useful resource for those in the field of networking, as well as students and individuals interested in the technical aspects of networking.
Subnet mask can be entered "windows" style, like 255.255.255.240, and "router" style - with simple number of bits in the mask, like 24.