IPv4 / IPv6 Subnet & CIDR Calculator
Enter an address in CIDR notation. IPv4 and IPv6 are both supported and detected automatically. Everything is computed locally in your browser.
📖 Guide: CIDR & subnetting explained
Last updated: August 29, 2026
Enter an address in CIDR notation. IPv4 and IPv6 are both supported and detected automatically. Everything is computed locally in your browser.
📖 Guide: CIDR & subnetting explained
Last updated: August 29, 2026