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/ipv6-subnet-calculator
IPv6 Subnet Calculator
Calculate the network address and range for an IPv6 CIDR block.
About IPv6 Subnet Calculator
IPv6 Subnet Calculator takes an IPv6 CIDR block and works out its network address, its last address, and the total number of addresses it contains, entirely in your browser.
Reach for this when planning how to divide an IPv6 allocation into smaller subnets, or when trying to build an intuition for just how large IPv6's address space is compared to IPv4's.
IPv6 has no concept of a reserved broadcast address the way IPv4 does, so the total address count shown here is the full size of the block, not a smaller usable-hosts figure with two addresses subtracted.
Tutorials
How IP Lookup, ASN and Geolocation Data Actually WorksWhat an autonomous system is, why an IP's location is only ever approximate, and what an IP or ASN lookup can honestly tell you about an address.6 min readIPv4 vs IPv6, and Why Some Sites Still Are Not Reachable Over ItThe practical difference between the two addressing systems, why IPv6 adoption is still incomplete after more than two decades, and how to check whether a domain supports it.5 min readMAC Addresses and IP Addresses, What They RevealThe difference between a device's hardware address and its network address, and what each one can and cannot tell you about a device.6 min read