IPv6 Address Types: GUA, ULA, Link-Local
Unlike IPv4, an IPv6 interface normally holds several addresses at once, each with a different scope.
| Type | Prefix | Scope / Use |
|---|---|---|
| Global Unicast (GUA) | 2000::/3 |
Public, globally routable |
| Unique Local (ULA) | fc00::/7 |
Private, like RFC 1918 in IPv4 |
| Link-Local | fe80::/10 |
One link only; auto-configured, always present |
| Loopback | ::1 |
The host itself |
| Unspecified | :: |
"No address yet" |
| Multicast | ff00::/8 |
Group delivery (replaces broadcast) |
Link-Local Is Always There
Every IPv6-enabled interface automatically generates a link-local fe80:: address used for neighbor discovery and routing on the local segment. It is not routable beyond the link.
ULA vs GUA
ULA (fc00::/7, in practice fd00::/8) is for internal networks that should not appear on the public Internet — the IPv6 equivalent of private IPv4 ranges. GUA is what you get for public, end-to-end reachable addresses.
Paste any IPv6 address into the IP converter to expand or compress it, or into the subnet calculator to see its range.