DevPrism
Network

IPv4 Subnet Calculatorclient-side

Break an IPv4 CIDR block down into its network and broadcast address, usable host range, mask, and size.

IPv4 Range Expander

Enter the first and last address of a range and get the smallest CIDR block that covers it.

IPv6 ULA Generator

Roll a random IPv6 unique local address prefix (fd00::/8) for private networks, following RFC 4193.