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ASNmap

Go CLI and Library for quickly mapping organization network ranges using ASN information.

Netmasks / Subnetting

Overview of network CIDR, Addresses, Hosts, Netmask and amount of clients.

cidr2ip

This program converts IPv4 CIDR blocks into their constituent IP addresses.

Subnet Calculator

Subnet calculator written in Python. It takes IP address and subnet mask as an input and returns for a given subnet network and broadcast address, first and last IP host, wildcard mask and number of usable hosts.