Subnets·IPv6 /62
IPv6
/62
2^66

IPv6 /62 prefix

/62 means the first 62 bits are the network and 66 are left for hosts. That is 2^66 addresses.

Addresses are 128 bits, so nobody writes a mask — only the prefix length. A home gets a /56, a single network a /64.

Prefix
/62
Host bits
66
Addresses
2^66
Usable hosts
2^66
/64 networks inside
2^66
Nibble boundary
No

Prefixes either side

How to read this

  • /24 means the first 24 bits are the network; the remaining 8 hold the addresses inside it.
  • Each extra bit splits the network in two and halves the addresses.
  • Usable addresses are normally the total minus two — the network and broadcast addresses.
  • IPv6 has no broadcast, so nothing is subtracted. One network is conventionally a /64.

Frequently asked questions

Q. How many addresses are in a /62?

2^66, of which 2^66 can actually be handed out.

Q. How is a /62 written?

IPv6 uses no mask — you simply write /62.

Q. How many /64 networks fit in a /62?

2^66.

Q. How many host bits are there?

66. Each extra network bit halves the addresses.