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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Network67.231.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
67.231.0.0
Broadcast address
67.231.255.255
First usable
67.231.0.1
Last usable
67.231.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
A (default /8)
As numbers
Hex 43E70000 · Integer 1139212288 to 1139277823
Reverse DNS zone
231.67.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01000011.11100111..00000000.0000000067.231.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01000011.11100111..00000000.0000000067.231.0.0
Broadcast01000011.11100111..11111111.1111111167.231.255.255
Split into smaller subnets/28

67.231.0.0/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
167.231.0.0/2867.231.0.1 to 67.231.0.1467.231.0.1514
267.231.0.16/2867.231.0.17 to 67.231.0.3067.231.0.3114
367.231.0.32/2867.231.0.33 to 67.231.0.4667.231.0.4714
467.231.0.48/2867.231.0.49 to 67.231.0.6267.231.0.6314
567.231.0.64/2867.231.0.65 to 67.231.0.7867.231.0.7914
667.231.0.80/2867.231.0.81 to 67.231.0.9467.231.0.9514
767.231.0.96/2867.231.0.97 to 67.231.0.11067.231.0.11114
867.231.0.112/2867.231.0.113 to 67.231.0.12667.231.0.12714
967.231.0.128/2867.231.0.129 to 67.231.0.14267.231.0.14314
1067.231.0.144/2867.231.0.145 to 67.231.0.15867.231.0.15914
1167.231.0.160/2867.231.0.161 to 67.231.0.17467.231.0.17514
1267.231.0.176/2867.231.0.177 to 67.231.0.19067.231.0.19114
1367.231.0.192/2867.231.0.193 to 67.231.0.20667.231.0.20714
1467.231.0.208/2867.231.0.209 to 67.231.0.22267.231.0.22314
1567.231.0.224/2867.231.0.225 to 67.231.0.23867.231.0.23914
1667.231.0.240/2867.231.0.241 to 67.231.0.25467.231.0.25514
1767.231.1.0/2867.231.1.1 to 67.231.1.1467.231.1.1514
1867.231.1.16/2867.231.1.17 to 67.231.1.3067.231.1.3114
1967.231.1.32/2867.231.1.33 to 67.231.1.4667.231.1.4714
2067.231.1.48/2867.231.1.49 to 67.231.1.6267.231.1.6314
2167.231.1.64/2867.231.1.65 to 67.231.1.7867.231.1.7914
2267.231.1.80/2867.231.1.81 to 67.231.1.9467.231.1.9514
2367.231.1.96/2867.231.1.97 to 67.231.1.11067.231.1.11114
2467.231.1.112/2867.231.1.113 to 67.231.1.12667.231.1.12714
2567.231.1.128/2867.231.1.129 to 67.231.1.14267.231.1.14314
2667.231.1.144/2867.231.1.145 to 67.231.1.15867.231.1.15914
2767.231.1.160/2867.231.1.161 to 67.231.1.17467.231.1.17514
2867.231.1.176/2867.231.1.177 to 67.231.1.19067.231.1.19114
2967.231.1.192/2867.231.1.193 to 67.231.1.20667.231.1.20714
3067.231.1.208/2867.231.1.209 to 67.231.1.22267.231.1.22314
3167.231.1.224/2867.231.1.225 to 67.231.1.23867.231.1.23914
3267.231.1.240/2867.231.1.241 to 67.231.1.25467.231.1.25514
3367.231.2.0/2867.231.2.1 to 67.231.2.1467.231.2.1514
3467.231.2.16/2867.231.2.17 to 67.231.2.3067.231.2.3114
3567.231.2.32/2867.231.2.33 to 67.231.2.4667.231.2.4714
3667.231.2.48/2867.231.2.49 to 67.231.2.6267.231.2.6314
3767.231.2.64/2867.231.2.65 to 67.231.2.7867.231.2.7914
3867.231.2.80/2867.231.2.81 to 67.231.2.9467.231.2.9514
3967.231.2.96/2867.231.2.97 to 67.231.2.11067.231.2.11114
4067.231.2.112/2867.231.2.113 to 67.231.2.12667.231.2.12714
4167.231.2.128/2867.231.2.129 to 67.231.2.14267.231.2.14314
4267.231.2.144/2867.231.2.145 to 67.231.2.15867.231.2.15914
4367.231.2.160/2867.231.2.161 to 67.231.2.17467.231.2.17514
4467.231.2.176/2867.231.2.177 to 67.231.2.19067.231.2.19114
4567.231.2.192/2867.231.2.193 to 67.231.2.20667.231.2.20714
4667.231.2.208/2867.231.2.209 to 67.231.2.22267.231.2.22314
4767.231.2.224/2867.231.2.225 to 67.231.2.23867.231.2.23914
4867.231.2.240/2867.231.2.241 to 67.231.2.25467.231.2.25514
4967.231.3.0/2867.231.3.1 to 67.231.3.1467.231.3.1514
5067.231.3.16/2867.231.3.17 to 67.231.3.3067.231.3.3114
5167.231.3.32/2867.231.3.33 to 67.231.3.4667.231.3.4714
5267.231.3.48/2867.231.3.49 to 67.231.3.6267.231.3.6314
5367.231.3.64/2867.231.3.65 to 67.231.3.7867.231.3.7914
5467.231.3.80/2867.231.3.81 to 67.231.3.9467.231.3.9514
5567.231.3.96/2867.231.3.97 to 67.231.3.11067.231.3.11114
5667.231.3.112/2867.231.3.113 to 67.231.3.12667.231.3.12714
5767.231.3.128/2867.231.3.129 to 67.231.3.14267.231.3.14314
5867.231.3.144/2867.231.3.145 to 67.231.3.15867.231.3.15914
5967.231.3.160/2867.231.3.161 to 67.231.3.17467.231.3.17514
6067.231.3.176/2867.231.3.177 to 67.231.3.19067.231.3.19114
6167.231.3.192/2867.231.3.193 to 67.231.3.20667.231.3.20714
6267.231.3.208/2867.231.3.209 to 67.231.3.22267.231.3.22314
6367.231.3.224/2867.231.3.225 to 67.231.3.23867.231.3.23914
6467.231.3.240/2867.231.3.241 to 67.231.3.25467.231.3.25514
6567.231.4.0/2867.231.4.1 to 67.231.4.1467.231.4.1514
6667.231.4.16/2867.231.4.17 to 67.231.4.3067.231.4.3114
6767.231.4.32/2867.231.4.33 to 67.231.4.4667.231.4.4714
6867.231.4.48/2867.231.4.49 to 67.231.4.6267.231.4.6314
6967.231.4.64/2867.231.4.65 to 67.231.4.7867.231.4.7914
7067.231.4.80/2867.231.4.81 to 67.231.4.9467.231.4.9514
7167.231.4.96/2867.231.4.97 to 67.231.4.11067.231.4.11114
7267.231.4.112/2867.231.4.113 to 67.231.4.12667.231.4.12714
7367.231.4.128/2867.231.4.129 to 67.231.4.14267.231.4.14314
7467.231.4.144/2867.231.4.145 to 67.231.4.15867.231.4.15914
7567.231.4.160/2867.231.4.161 to 67.231.4.17467.231.4.17514
7667.231.4.176/2867.231.4.177 to 67.231.4.19067.231.4.19114
7767.231.4.192/2867.231.4.193 to 67.231.4.20667.231.4.20714
7867.231.4.208/2867.231.4.209 to 67.231.4.22267.231.4.22314
7967.231.4.224/2867.231.4.225 to 67.231.4.23867.231.4.23914
8067.231.4.240/2867.231.4.241 to 67.231.4.25467.231.4.25514
8167.231.5.0/2867.231.5.1 to 67.231.5.1467.231.5.1514
8267.231.5.16/2867.231.5.17 to 67.231.5.3067.231.5.3114
8367.231.5.32/2867.231.5.33 to 67.231.5.4667.231.5.4714
8467.231.5.48/2867.231.5.49 to 67.231.5.6267.231.5.6314
8567.231.5.64/2867.231.5.65 to 67.231.5.7867.231.5.7914
8667.231.5.80/2867.231.5.81 to 67.231.5.9467.231.5.9514
8767.231.5.96/2867.231.5.97 to 67.231.5.11067.231.5.11114
8867.231.5.112/2867.231.5.113 to 67.231.5.12667.231.5.12714
8967.231.5.128/2867.231.5.129 to 67.231.5.14267.231.5.14314
9067.231.5.144/2867.231.5.145 to 67.231.5.15867.231.5.15914
9167.231.5.160/2867.231.5.161 to 67.231.5.17467.231.5.17514
9267.231.5.176/2867.231.5.177 to 67.231.5.19067.231.5.19114
9367.231.5.192/2867.231.5.193 to 67.231.5.20667.231.5.20714
9467.231.5.208/2867.231.5.209 to 67.231.5.22267.231.5.22314
9567.231.5.224/2867.231.5.225 to 67.231.5.23867.231.5.23914
9667.231.5.240/2867.231.5.241 to 67.231.5.25467.231.5.25514
9767.231.6.0/2867.231.6.1 to 67.231.6.1467.231.6.1514
9867.231.6.16/2867.231.6.17 to 67.231.6.3067.231.6.3114
9967.231.6.32/2867.231.6.33 to 67.231.6.4667.231.6.4714
10067.231.6.48/2867.231.6.49 to 67.231.6.6267.231.6.6314
10167.231.6.64/2867.231.6.65 to 67.231.6.7867.231.6.7914
10267.231.6.80/2867.231.6.81 to 67.231.6.9467.231.6.9514
10367.231.6.96/2867.231.6.97 to 67.231.6.11067.231.6.11114
10467.231.6.112/2867.231.6.113 to 67.231.6.12667.231.6.12714
10567.231.6.128/2867.231.6.129 to 67.231.6.14267.231.6.14314
10667.231.6.144/2867.231.6.145 to 67.231.6.15867.231.6.15914
10767.231.6.160/2867.231.6.161 to 67.231.6.17467.231.6.17514
10867.231.6.176/2867.231.6.177 to 67.231.6.19067.231.6.19114
10967.231.6.192/2867.231.6.193 to 67.231.6.20667.231.6.20714
11067.231.6.208/2867.231.6.209 to 67.231.6.22267.231.6.22314
11167.231.6.224/2867.231.6.225 to 67.231.6.23867.231.6.23914
11267.231.6.240/2867.231.6.241 to 67.231.6.25467.231.6.25514
11367.231.7.0/2867.231.7.1 to 67.231.7.1467.231.7.1514
11467.231.7.16/2867.231.7.17 to 67.231.7.3067.231.7.3114
11567.231.7.32/2867.231.7.33 to 67.231.7.4667.231.7.4714
11667.231.7.48/2867.231.7.49 to 67.231.7.6267.231.7.6314
11767.231.7.64/2867.231.7.65 to 67.231.7.7867.231.7.7914
11867.231.7.80/2867.231.7.81 to 67.231.7.9467.231.7.9514
11967.231.7.96/2867.231.7.97 to 67.231.7.11067.231.7.11114
12067.231.7.112/2867.231.7.113 to 67.231.7.12667.231.7.12714
12167.231.7.128/2867.231.7.129 to 67.231.7.14267.231.7.14314
12267.231.7.144/2867.231.7.145 to 67.231.7.15867.231.7.15914
12367.231.7.160/2867.231.7.161 to 67.231.7.17467.231.7.17514
12467.231.7.176/2867.231.7.177 to 67.231.7.19067.231.7.19114
12567.231.7.192/2867.231.7.193 to 67.231.7.20667.231.7.20714
12667.231.7.208/2867.231.7.209 to 67.231.7.22267.231.7.22314
12767.231.7.224/2867.231.7.225 to 67.231.7.23867.231.7.23914
12867.231.7.240/2867.231.7.241 to 67.231.7.25467.231.7.25514
12967.231.8.0/2867.231.8.1 to 67.231.8.1467.231.8.1514
13067.231.8.16/2867.231.8.17 to 67.231.8.3067.231.8.3114
13167.231.8.32/2867.231.8.33 to 67.231.8.4667.231.8.4714
13267.231.8.48/2867.231.8.49 to 67.231.8.6267.231.8.6314
13367.231.8.64/2867.231.8.65 to 67.231.8.7867.231.8.7914
13467.231.8.80/2867.231.8.81 to 67.231.8.9467.231.8.9514
13567.231.8.96/2867.231.8.97 to 67.231.8.11067.231.8.11114
13667.231.8.112/2867.231.8.113 to 67.231.8.12667.231.8.12714
13767.231.8.128/2867.231.8.129 to 67.231.8.14267.231.8.14314
13867.231.8.144/2867.231.8.145 to 67.231.8.15867.231.8.15914
13967.231.8.160/2867.231.8.161 to 67.231.8.17467.231.8.17514
14067.231.8.176/2867.231.8.177 to 67.231.8.19067.231.8.19114
14167.231.8.192/2867.231.8.193 to 67.231.8.20667.231.8.20714
14267.231.8.208/2867.231.8.209 to 67.231.8.22267.231.8.22314
14367.231.8.224/2867.231.8.225 to 67.231.8.23867.231.8.23914
14467.231.8.240/2867.231.8.241 to 67.231.8.25467.231.8.25514
14567.231.9.0/2867.231.9.1 to 67.231.9.1467.231.9.1514
14667.231.9.16/2867.231.9.17 to 67.231.9.3067.231.9.3114
14767.231.9.32/2867.231.9.33 to 67.231.9.4667.231.9.4714
14867.231.9.48/2867.231.9.49 to 67.231.9.6267.231.9.6314
14967.231.9.64/2867.231.9.65 to 67.231.9.7867.231.9.7914
15067.231.9.80/2867.231.9.81 to 67.231.9.9467.231.9.9514
15167.231.9.96/2867.231.9.97 to 67.231.9.11067.231.9.11114
15267.231.9.112/2867.231.9.113 to 67.231.9.12667.231.9.12714
15367.231.9.128/2867.231.9.129 to 67.231.9.14267.231.9.14314
15467.231.9.144/2867.231.9.145 to 67.231.9.15867.231.9.15914
15567.231.9.160/2867.231.9.161 to 67.231.9.17467.231.9.17514
15667.231.9.176/2867.231.9.177 to 67.231.9.19067.231.9.19114
15767.231.9.192/2867.231.9.193 to 67.231.9.20667.231.9.20714
15867.231.9.208/2867.231.9.209 to 67.231.9.22267.231.9.22314
15967.231.9.224/2867.231.9.225 to 67.231.9.23867.231.9.23914
16067.231.9.240/2867.231.9.241 to 67.231.9.25467.231.9.25514
16167.231.10.0/2867.231.10.1 to 67.231.10.1467.231.10.1514
16267.231.10.16/2867.231.10.17 to 67.231.10.3067.231.10.3114
16367.231.10.32/2867.231.10.33 to 67.231.10.4667.231.10.4714
16467.231.10.48/2867.231.10.49 to 67.231.10.6267.231.10.6314
16567.231.10.64/2867.231.10.65 to 67.231.10.7867.231.10.7914
16667.231.10.80/2867.231.10.81 to 67.231.10.9467.231.10.9514
16767.231.10.96/2867.231.10.97 to 67.231.10.11067.231.10.11114
16867.231.10.112/2867.231.10.113 to 67.231.10.12667.231.10.12714
16967.231.10.128/2867.231.10.129 to 67.231.10.14267.231.10.14314
17067.231.10.144/2867.231.10.145 to 67.231.10.15867.231.10.15914
17167.231.10.160/2867.231.10.161 to 67.231.10.17467.231.10.17514
17267.231.10.176/2867.231.10.177 to 67.231.10.19067.231.10.19114
17367.231.10.192/2867.231.10.193 to 67.231.10.20667.231.10.20714
17467.231.10.208/2867.231.10.209 to 67.231.10.22267.231.10.22314
17567.231.10.224/2867.231.10.225 to 67.231.10.23867.231.10.23914
17667.231.10.240/2867.231.10.241 to 67.231.10.25467.231.10.25514
17767.231.11.0/2867.231.11.1 to 67.231.11.1467.231.11.1514
17867.231.11.16/2867.231.11.17 to 67.231.11.3067.231.11.3114
17967.231.11.32/2867.231.11.33 to 67.231.11.4667.231.11.4714
18067.231.11.48/2867.231.11.49 to 67.231.11.6267.231.11.6314
18167.231.11.64/2867.231.11.65 to 67.231.11.7867.231.11.7914
18267.231.11.80/2867.231.11.81 to 67.231.11.9467.231.11.9514
18367.231.11.96/2867.231.11.97 to 67.231.11.11067.231.11.11114
18467.231.11.112/2867.231.11.113 to 67.231.11.12667.231.11.12714
18567.231.11.128/2867.231.11.129 to 67.231.11.14267.231.11.14314
18667.231.11.144/2867.231.11.145 to 67.231.11.15867.231.11.15914
18767.231.11.160/2867.231.11.161 to 67.231.11.17467.231.11.17514
18867.231.11.176/2867.231.11.177 to 67.231.11.19067.231.11.19114
18967.231.11.192/2867.231.11.193 to 67.231.11.20667.231.11.20714
19067.231.11.208/2867.231.11.209 to 67.231.11.22267.231.11.22314
19167.231.11.224/2867.231.11.225 to 67.231.11.23867.231.11.23914
19267.231.11.240/2867.231.11.241 to 67.231.11.25467.231.11.25514
19367.231.12.0/2867.231.12.1 to 67.231.12.1467.231.12.1514
19467.231.12.16/2867.231.12.17 to 67.231.12.3067.231.12.3114
19567.231.12.32/2867.231.12.33 to 67.231.12.4667.231.12.4714
19667.231.12.48/2867.231.12.49 to 67.231.12.6267.231.12.6314
19767.231.12.64/2867.231.12.65 to 67.231.12.7867.231.12.7914
19867.231.12.80/2867.231.12.81 to 67.231.12.9467.231.12.9514
19967.231.12.96/2867.231.12.97 to 67.231.12.11067.231.12.11114
20067.231.12.112/2867.231.12.113 to 67.231.12.12667.231.12.12714
20167.231.12.128/2867.231.12.129 to 67.231.12.14267.231.12.14314
20267.231.12.144/2867.231.12.145 to 67.231.12.15867.231.12.15914
20367.231.12.160/2867.231.12.161 to 67.231.12.17467.231.12.17514
20467.231.12.176/2867.231.12.177 to 67.231.12.19067.231.12.19114
20567.231.12.192/2867.231.12.193 to 67.231.12.20667.231.12.20714
20667.231.12.208/2867.231.12.209 to 67.231.12.22267.231.12.22314
20767.231.12.224/2867.231.12.225 to 67.231.12.23867.231.12.23914
20867.231.12.240/2867.231.12.241 to 67.231.12.25467.231.12.25514
20967.231.13.0/2867.231.13.1 to 67.231.13.1467.231.13.1514
21067.231.13.16/2867.231.13.17 to 67.231.13.3067.231.13.3114
21167.231.13.32/2867.231.13.33 to 67.231.13.4667.231.13.4714
21267.231.13.48/2867.231.13.49 to 67.231.13.6267.231.13.6314
21367.231.13.64/2867.231.13.65 to 67.231.13.7867.231.13.7914
21467.231.13.80/2867.231.13.81 to 67.231.13.9467.231.13.9514
21567.231.13.96/2867.231.13.97 to 67.231.13.11067.231.13.11114
21667.231.13.112/2867.231.13.113 to 67.231.13.12667.231.13.12714
21767.231.13.128/2867.231.13.129 to 67.231.13.14267.231.13.14314
21867.231.13.144/2867.231.13.145 to 67.231.13.15867.231.13.15914
21967.231.13.160/2867.231.13.161 to 67.231.13.17467.231.13.17514
22067.231.13.176/2867.231.13.177 to 67.231.13.19067.231.13.19114
22167.231.13.192/2867.231.13.193 to 67.231.13.20667.231.13.20714
22267.231.13.208/2867.231.13.209 to 67.231.13.22267.231.13.22314
22367.231.13.224/2867.231.13.225 to 67.231.13.23867.231.13.23914
22467.231.13.240/2867.231.13.241 to 67.231.13.25467.231.13.25514
22567.231.14.0/2867.231.14.1 to 67.231.14.1467.231.14.1514
22667.231.14.16/2867.231.14.17 to 67.231.14.3067.231.14.3114
22767.231.14.32/2867.231.14.33 to 67.231.14.4667.231.14.4714
22867.231.14.48/2867.231.14.49 to 67.231.14.6267.231.14.6314
22967.231.14.64/2867.231.14.65 to 67.231.14.7867.231.14.7914
23067.231.14.80/2867.231.14.81 to 67.231.14.9467.231.14.9514
23167.231.14.96/2867.231.14.97 to 67.231.14.11067.231.14.11114
23267.231.14.112/2867.231.14.113 to 67.231.14.12667.231.14.12714
23367.231.14.128/2867.231.14.129 to 67.231.14.14267.231.14.14314
23467.231.14.144/2867.231.14.145 to 67.231.14.15867.231.14.15914
23567.231.14.160/2867.231.14.161 to 67.231.14.17467.231.14.17514
23667.231.14.176/2867.231.14.177 to 67.231.14.19067.231.14.19114
23767.231.14.192/2867.231.14.193 to 67.231.14.20667.231.14.20714
23867.231.14.208/2867.231.14.209 to 67.231.14.22267.231.14.22314
23967.231.14.224/2867.231.14.225 to 67.231.14.23867.231.14.23914
24067.231.14.240/2867.231.14.241 to 67.231.14.25467.231.14.25514
24167.231.15.0/2867.231.15.1 to 67.231.15.1467.231.15.1514
24267.231.15.16/2867.231.15.17 to 67.231.15.3067.231.15.3114
24367.231.15.32/2867.231.15.33 to 67.231.15.4667.231.15.4714
24467.231.15.48/2867.231.15.49 to 67.231.15.6267.231.15.6314
24567.231.15.64/2867.231.15.65 to 67.231.15.7867.231.15.7914
24667.231.15.80/2867.231.15.81 to 67.231.15.9467.231.15.9514
24767.231.15.96/2867.231.15.97 to 67.231.15.11067.231.15.11114
24867.231.15.112/2867.231.15.113 to 67.231.15.12667.231.15.12714
24967.231.15.128/2867.231.15.129 to 67.231.15.14267.231.15.14314
25067.231.15.144/2867.231.15.145 to 67.231.15.15867.231.15.15914
25167.231.15.160/2867.231.15.161 to 67.231.15.17467.231.15.17514
25267.231.15.176/2867.231.15.177 to 67.231.15.19067.231.15.19114
25367.231.15.192/2867.231.15.193 to 67.231.15.20667.231.15.20714
25467.231.15.208/2867.231.15.209 to 67.231.15.22267.231.15.22314
25567.231.15.224/2867.231.15.225 to 67.231.15.23867.231.15.23914
25667.231.15.240/2867.231.15.241 to 67.231.15.25467.231.15.25514

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses