IPv6 for People Who Know IPv4

IPv6 has 128 bits instead of 32 — that is 340 undecillion addresses. The notation looks different but the ideas carry over.

Notation

Eight groups of four hex digits, separated by colons. Leading zeros drop, and one run of all-zero groups collapses to ::. So 2001:0db8:0000:0000:0000:0000:0000:0001 becomes 2001:db8::1.

Prefixes

A typical site gets a /48, each LAN a /64. Expand or compress any address with our IPv6 tool.