IPv6 Subnet Calculator
Enter an IPv6 address with a prefix to see its network, address range, number of /64 subnets, and its full and short forms. You can also split the prefix into smaller subnets.
documentation2001:db8:cd00::/40
network2001:db8:cd00::/40
first host2001:db8:cd00::
last host2001:db8:cdff:ffff:ffff:ffff:ffff:ffff
addresses2⁸⁸ = 309,485,009,821,345,068,724,781,056
/64 subnets16,777,216
short form2001:db8:cd00::
ipcalc 2001:db8:cd00::/40
address2001:0db8:cd00:0000:0000:0000:0000:0000
network2001:0db8:cd00:0000:0000:0000:0000:0000
last host2001:0db8:cdff:ffff:ffff:ffff:ffff:ffff
green = network digits, amber = digit split by the prefix
full form2001:0db8:cd00:0000:0000:0000:0000:0000
reverse dns0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.d.c.8.b.d.0.1.0.0.2.ip6.arpa
01 / table
IPv6 prefix table.
Click a prefix longer than your network to split it into subnets.
| prefix | addresses | /64 subnets | in your /40 |
|---|---|---|---|
| /8 | 2¹²⁰ | 2⁵⁶ | - |
| /12 | 2¹¹⁶ | 2⁵² | - |
| /16 | 2¹¹² | 2⁴⁸ | - |
| /20 | 2¹⁰⁸ | 2⁴⁴ | - |
| /24 | 2¹⁰⁴ | 2⁴⁰ | - |
| /28 | 2¹⁰⁰ | 2³⁶ | - |
| /32 | 2⁹⁶ | 4,294,967,296 | - |
| /36 | 2⁹² | 268,435,456 | - |
| /40 | 2⁸⁸ | 16,777,216 | 1 |
| /44 | 2⁸⁴ | 1,048,576 | 16 split → |
| /48 | 2⁸⁰ | 65,536 | 256 split → |
| /52 | 2⁷⁶ | 4,096 | 4,096 split → |
| /56 | 2⁷² | 256 | 65,536 split → |
| /60 | 2⁶⁸ | 16 | 1,048,576 split → |
| /64 | 2⁶⁴ | 1 | 16,777,216 split → |
| /72 | 2⁵⁶ | - | 4,294,967,296 split → |
| /80 | 2⁴⁸ | - | 2⁴⁰ split → |
| /96 | 4,294,967,296 | - | 2⁵⁶ split → |
| /112 | 65,536 | - | 2⁷² split → |
| /120 | 256 | - | 2⁸⁰ split → |
| /124 | 16 | - | 2⁸⁴ split → |
| /126 | 4 | - | 2⁸⁶ split → |
| /127 | 2 | - | 2⁸⁷ split → |
| /128 | 1 | - | 2⁸⁸ split → |
02 / faq
About this calculator.
How do I use this IPv6 calculator?
▼
Type an IPv6 address followed by a prefix, like 2001:db8:abcd::1/48. Without a prefix it uses /64. The address can be written in full or shortened with ::.
Why does IPv6 have no broadcast address?
▼
IPv6 replaced broadcast with multicast, so no address is set aside for it. That is why this calculator shows the whole range, from the network address to the last address.
What prefix do ISPs usually hand out?
▼
A single LAN is almost always a /64. Home customers usually get a /56 or /60, and an organization or site usually gets a /48. One /48 holds 65,536 /64 subnets.