ip-calculator.uptool.net · tools
IPv6 subnet calculator
Paste an IPv6 address and prefix (or use address/prefix in one field).
IPv6 uses different on-link rules than IPv4 broadcast; /64 is common for LANs but not assumed here.
IPv6 has no IPv4-style broadcast; this tool shows the subnet ID (network), last address in the prefix, and how many addresses the prefix covers. A sample result is calculated when the page opens.
IPv6 planning
Useful when you:
- Check whether an address sits inside a delegated prefix
- Copy the compressed network string for templates
- Compare address counts across prefix lengths
Still pairs with IPv8 n field
Inside draft IPv8, the outer r scope is separate; this IPv6 page is for native IPv6 prefix math only.