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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.

Network94.3.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
94.3.0.0
Broadcast address
94.3.255.255
First usable
94.3.0.1
Last usable
94.3.255.254
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 5E030000 · Integer 1577254912 to 1577320447
Reverse DNS zone
3.94.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011110.00000011..00000000.0000000094.3.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01011110.00000011..00000000.0000000094.3.0.0
Broadcast01011110.00000011..11111111.1111111194.3.255.255
Split into smaller subnets/28

94.3.0.0/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
194.3.0.0/2894.3.0.1 to 94.3.0.1494.3.0.1514
294.3.0.16/2894.3.0.17 to 94.3.0.3094.3.0.3114
394.3.0.32/2894.3.0.33 to 94.3.0.4694.3.0.4714
494.3.0.48/2894.3.0.49 to 94.3.0.6294.3.0.6314
594.3.0.64/2894.3.0.65 to 94.3.0.7894.3.0.7914
694.3.0.80/2894.3.0.81 to 94.3.0.9494.3.0.9514
794.3.0.96/2894.3.0.97 to 94.3.0.11094.3.0.11114
894.3.0.112/2894.3.0.113 to 94.3.0.12694.3.0.12714
994.3.0.128/2894.3.0.129 to 94.3.0.14294.3.0.14314
1094.3.0.144/2894.3.0.145 to 94.3.0.15894.3.0.15914
1194.3.0.160/2894.3.0.161 to 94.3.0.17494.3.0.17514
1294.3.0.176/2894.3.0.177 to 94.3.0.19094.3.0.19114
1394.3.0.192/2894.3.0.193 to 94.3.0.20694.3.0.20714
1494.3.0.208/2894.3.0.209 to 94.3.0.22294.3.0.22314
1594.3.0.224/2894.3.0.225 to 94.3.0.23894.3.0.23914
1694.3.0.240/2894.3.0.241 to 94.3.0.25494.3.0.25514
1794.3.1.0/2894.3.1.1 to 94.3.1.1494.3.1.1514
1894.3.1.16/2894.3.1.17 to 94.3.1.3094.3.1.3114
1994.3.1.32/2894.3.1.33 to 94.3.1.4694.3.1.4714
2094.3.1.48/2894.3.1.49 to 94.3.1.6294.3.1.6314
2194.3.1.64/2894.3.1.65 to 94.3.1.7894.3.1.7914
2294.3.1.80/2894.3.1.81 to 94.3.1.9494.3.1.9514
2394.3.1.96/2894.3.1.97 to 94.3.1.11094.3.1.11114
2494.3.1.112/2894.3.1.113 to 94.3.1.12694.3.1.12714
2594.3.1.128/2894.3.1.129 to 94.3.1.14294.3.1.14314
2694.3.1.144/2894.3.1.145 to 94.3.1.15894.3.1.15914
2794.3.1.160/2894.3.1.161 to 94.3.1.17494.3.1.17514
2894.3.1.176/2894.3.1.177 to 94.3.1.19094.3.1.19114
2994.3.1.192/2894.3.1.193 to 94.3.1.20694.3.1.20714
3094.3.1.208/2894.3.1.209 to 94.3.1.22294.3.1.22314
3194.3.1.224/2894.3.1.225 to 94.3.1.23894.3.1.23914
3294.3.1.240/2894.3.1.241 to 94.3.1.25494.3.1.25514
3394.3.2.0/2894.3.2.1 to 94.3.2.1494.3.2.1514
3494.3.2.16/2894.3.2.17 to 94.3.2.3094.3.2.3114
3594.3.2.32/2894.3.2.33 to 94.3.2.4694.3.2.4714
3694.3.2.48/2894.3.2.49 to 94.3.2.6294.3.2.6314
3794.3.2.64/2894.3.2.65 to 94.3.2.7894.3.2.7914
3894.3.2.80/2894.3.2.81 to 94.3.2.9494.3.2.9514
3994.3.2.96/2894.3.2.97 to 94.3.2.11094.3.2.11114
4094.3.2.112/2894.3.2.113 to 94.3.2.12694.3.2.12714
4194.3.2.128/2894.3.2.129 to 94.3.2.14294.3.2.14314
4294.3.2.144/2894.3.2.145 to 94.3.2.15894.3.2.15914
4394.3.2.160/2894.3.2.161 to 94.3.2.17494.3.2.17514
4494.3.2.176/2894.3.2.177 to 94.3.2.19094.3.2.19114
4594.3.2.192/2894.3.2.193 to 94.3.2.20694.3.2.20714
4694.3.2.208/2894.3.2.209 to 94.3.2.22294.3.2.22314
4794.3.2.224/2894.3.2.225 to 94.3.2.23894.3.2.23914
4894.3.2.240/2894.3.2.241 to 94.3.2.25494.3.2.25514
4994.3.3.0/2894.3.3.1 to 94.3.3.1494.3.3.1514
5094.3.3.16/2894.3.3.17 to 94.3.3.3094.3.3.3114
5194.3.3.32/2894.3.3.33 to 94.3.3.4694.3.3.4714
5294.3.3.48/2894.3.3.49 to 94.3.3.6294.3.3.6314
5394.3.3.64/2894.3.3.65 to 94.3.3.7894.3.3.7914
5494.3.3.80/2894.3.3.81 to 94.3.3.9494.3.3.9514
5594.3.3.96/2894.3.3.97 to 94.3.3.11094.3.3.11114
5694.3.3.112/2894.3.3.113 to 94.3.3.12694.3.3.12714
5794.3.3.128/2894.3.3.129 to 94.3.3.14294.3.3.14314
5894.3.3.144/2894.3.3.145 to 94.3.3.15894.3.3.15914
5994.3.3.160/2894.3.3.161 to 94.3.3.17494.3.3.17514
6094.3.3.176/2894.3.3.177 to 94.3.3.19094.3.3.19114
6194.3.3.192/2894.3.3.193 to 94.3.3.20694.3.3.20714
6294.3.3.208/2894.3.3.209 to 94.3.3.22294.3.3.22314
6394.3.3.224/2894.3.3.225 to 94.3.3.23894.3.3.23914
6494.3.3.240/2894.3.3.241 to 94.3.3.25494.3.3.25514
6594.3.4.0/2894.3.4.1 to 94.3.4.1494.3.4.1514
6694.3.4.16/2894.3.4.17 to 94.3.4.3094.3.4.3114
6794.3.4.32/2894.3.4.33 to 94.3.4.4694.3.4.4714
6894.3.4.48/2894.3.4.49 to 94.3.4.6294.3.4.6314
6994.3.4.64/2894.3.4.65 to 94.3.4.7894.3.4.7914
7094.3.4.80/2894.3.4.81 to 94.3.4.9494.3.4.9514
7194.3.4.96/2894.3.4.97 to 94.3.4.11094.3.4.11114
7294.3.4.112/2894.3.4.113 to 94.3.4.12694.3.4.12714
7394.3.4.128/2894.3.4.129 to 94.3.4.14294.3.4.14314
7494.3.4.144/2894.3.4.145 to 94.3.4.15894.3.4.15914
7594.3.4.160/2894.3.4.161 to 94.3.4.17494.3.4.17514
7694.3.4.176/2894.3.4.177 to 94.3.4.19094.3.4.19114
7794.3.4.192/2894.3.4.193 to 94.3.4.20694.3.4.20714
7894.3.4.208/2894.3.4.209 to 94.3.4.22294.3.4.22314
7994.3.4.224/2894.3.4.225 to 94.3.4.23894.3.4.23914
8094.3.4.240/2894.3.4.241 to 94.3.4.25494.3.4.25514
8194.3.5.0/2894.3.5.1 to 94.3.5.1494.3.5.1514
8294.3.5.16/2894.3.5.17 to 94.3.5.3094.3.5.3114
8394.3.5.32/2894.3.5.33 to 94.3.5.4694.3.5.4714
8494.3.5.48/2894.3.5.49 to 94.3.5.6294.3.5.6314
8594.3.5.64/2894.3.5.65 to 94.3.5.7894.3.5.7914
8694.3.5.80/2894.3.5.81 to 94.3.5.9494.3.5.9514
8794.3.5.96/2894.3.5.97 to 94.3.5.11094.3.5.11114
8894.3.5.112/2894.3.5.113 to 94.3.5.12694.3.5.12714
8994.3.5.128/2894.3.5.129 to 94.3.5.14294.3.5.14314
9094.3.5.144/2894.3.5.145 to 94.3.5.15894.3.5.15914
9194.3.5.160/2894.3.5.161 to 94.3.5.17494.3.5.17514
9294.3.5.176/2894.3.5.177 to 94.3.5.19094.3.5.19114
9394.3.5.192/2894.3.5.193 to 94.3.5.20694.3.5.20714
9494.3.5.208/2894.3.5.209 to 94.3.5.22294.3.5.22314
9594.3.5.224/2894.3.5.225 to 94.3.5.23894.3.5.23914
9694.3.5.240/2894.3.5.241 to 94.3.5.25494.3.5.25514
9794.3.6.0/2894.3.6.1 to 94.3.6.1494.3.6.1514
9894.3.6.16/2894.3.6.17 to 94.3.6.3094.3.6.3114
9994.3.6.32/2894.3.6.33 to 94.3.6.4694.3.6.4714
10094.3.6.48/2894.3.6.49 to 94.3.6.6294.3.6.6314
10194.3.6.64/2894.3.6.65 to 94.3.6.7894.3.6.7914
10294.3.6.80/2894.3.6.81 to 94.3.6.9494.3.6.9514
10394.3.6.96/2894.3.6.97 to 94.3.6.11094.3.6.11114
10494.3.6.112/2894.3.6.113 to 94.3.6.12694.3.6.12714
10594.3.6.128/2894.3.6.129 to 94.3.6.14294.3.6.14314
10694.3.6.144/2894.3.6.145 to 94.3.6.15894.3.6.15914
10794.3.6.160/2894.3.6.161 to 94.3.6.17494.3.6.17514
10894.3.6.176/2894.3.6.177 to 94.3.6.19094.3.6.19114
10994.3.6.192/2894.3.6.193 to 94.3.6.20694.3.6.20714
11094.3.6.208/2894.3.6.209 to 94.3.6.22294.3.6.22314
11194.3.6.224/2894.3.6.225 to 94.3.6.23894.3.6.23914
11294.3.6.240/2894.3.6.241 to 94.3.6.25494.3.6.25514
11394.3.7.0/2894.3.7.1 to 94.3.7.1494.3.7.1514
11494.3.7.16/2894.3.7.17 to 94.3.7.3094.3.7.3114
11594.3.7.32/2894.3.7.33 to 94.3.7.4694.3.7.4714
11694.3.7.48/2894.3.7.49 to 94.3.7.6294.3.7.6314
11794.3.7.64/2894.3.7.65 to 94.3.7.7894.3.7.7914
11894.3.7.80/2894.3.7.81 to 94.3.7.9494.3.7.9514
11994.3.7.96/2894.3.7.97 to 94.3.7.11094.3.7.11114
12094.3.7.112/2894.3.7.113 to 94.3.7.12694.3.7.12714
12194.3.7.128/2894.3.7.129 to 94.3.7.14294.3.7.14314
12294.3.7.144/2894.3.7.145 to 94.3.7.15894.3.7.15914
12394.3.7.160/2894.3.7.161 to 94.3.7.17494.3.7.17514
12494.3.7.176/2894.3.7.177 to 94.3.7.19094.3.7.19114
12594.3.7.192/2894.3.7.193 to 94.3.7.20694.3.7.20714
12694.3.7.208/2894.3.7.209 to 94.3.7.22294.3.7.22314
12794.3.7.224/2894.3.7.225 to 94.3.7.23894.3.7.23914
12894.3.7.240/2894.3.7.241 to 94.3.7.25494.3.7.25514
12994.3.8.0/2894.3.8.1 to 94.3.8.1494.3.8.1514
13094.3.8.16/2894.3.8.17 to 94.3.8.3094.3.8.3114
13194.3.8.32/2894.3.8.33 to 94.3.8.4694.3.8.4714
13294.3.8.48/2894.3.8.49 to 94.3.8.6294.3.8.6314
13394.3.8.64/2894.3.8.65 to 94.3.8.7894.3.8.7914
13494.3.8.80/2894.3.8.81 to 94.3.8.9494.3.8.9514
13594.3.8.96/2894.3.8.97 to 94.3.8.11094.3.8.11114
13694.3.8.112/2894.3.8.113 to 94.3.8.12694.3.8.12714
13794.3.8.128/2894.3.8.129 to 94.3.8.14294.3.8.14314
13894.3.8.144/2894.3.8.145 to 94.3.8.15894.3.8.15914
13994.3.8.160/2894.3.8.161 to 94.3.8.17494.3.8.17514
14094.3.8.176/2894.3.8.177 to 94.3.8.19094.3.8.19114
14194.3.8.192/2894.3.8.193 to 94.3.8.20694.3.8.20714
14294.3.8.208/2894.3.8.209 to 94.3.8.22294.3.8.22314
14394.3.8.224/2894.3.8.225 to 94.3.8.23894.3.8.23914
14494.3.8.240/2894.3.8.241 to 94.3.8.25494.3.8.25514
14594.3.9.0/2894.3.9.1 to 94.3.9.1494.3.9.1514
14694.3.9.16/2894.3.9.17 to 94.3.9.3094.3.9.3114
14794.3.9.32/2894.3.9.33 to 94.3.9.4694.3.9.4714
14894.3.9.48/2894.3.9.49 to 94.3.9.6294.3.9.6314
14994.3.9.64/2894.3.9.65 to 94.3.9.7894.3.9.7914
15094.3.9.80/2894.3.9.81 to 94.3.9.9494.3.9.9514
15194.3.9.96/2894.3.9.97 to 94.3.9.11094.3.9.11114
15294.3.9.112/2894.3.9.113 to 94.3.9.12694.3.9.12714
15394.3.9.128/2894.3.9.129 to 94.3.9.14294.3.9.14314
15494.3.9.144/2894.3.9.145 to 94.3.9.15894.3.9.15914
15594.3.9.160/2894.3.9.161 to 94.3.9.17494.3.9.17514
15694.3.9.176/2894.3.9.177 to 94.3.9.19094.3.9.19114
15794.3.9.192/2894.3.9.193 to 94.3.9.20694.3.9.20714
15894.3.9.208/2894.3.9.209 to 94.3.9.22294.3.9.22314
15994.3.9.224/2894.3.9.225 to 94.3.9.23894.3.9.23914
16094.3.9.240/2894.3.9.241 to 94.3.9.25494.3.9.25514
16194.3.10.0/2894.3.10.1 to 94.3.10.1494.3.10.1514
16294.3.10.16/2894.3.10.17 to 94.3.10.3094.3.10.3114
16394.3.10.32/2894.3.10.33 to 94.3.10.4694.3.10.4714
16494.3.10.48/2894.3.10.49 to 94.3.10.6294.3.10.6314
16594.3.10.64/2894.3.10.65 to 94.3.10.7894.3.10.7914
16694.3.10.80/2894.3.10.81 to 94.3.10.9494.3.10.9514
16794.3.10.96/2894.3.10.97 to 94.3.10.11094.3.10.11114
16894.3.10.112/2894.3.10.113 to 94.3.10.12694.3.10.12714
16994.3.10.128/2894.3.10.129 to 94.3.10.14294.3.10.14314
17094.3.10.144/2894.3.10.145 to 94.3.10.15894.3.10.15914
17194.3.10.160/2894.3.10.161 to 94.3.10.17494.3.10.17514
17294.3.10.176/2894.3.10.177 to 94.3.10.19094.3.10.19114
17394.3.10.192/2894.3.10.193 to 94.3.10.20694.3.10.20714
17494.3.10.208/2894.3.10.209 to 94.3.10.22294.3.10.22314
17594.3.10.224/2894.3.10.225 to 94.3.10.23894.3.10.23914
17694.3.10.240/2894.3.10.241 to 94.3.10.25494.3.10.25514
17794.3.11.0/2894.3.11.1 to 94.3.11.1494.3.11.1514
17894.3.11.16/2894.3.11.17 to 94.3.11.3094.3.11.3114
17994.3.11.32/2894.3.11.33 to 94.3.11.4694.3.11.4714
18094.3.11.48/2894.3.11.49 to 94.3.11.6294.3.11.6314
18194.3.11.64/2894.3.11.65 to 94.3.11.7894.3.11.7914
18294.3.11.80/2894.3.11.81 to 94.3.11.9494.3.11.9514
18394.3.11.96/2894.3.11.97 to 94.3.11.11094.3.11.11114
18494.3.11.112/2894.3.11.113 to 94.3.11.12694.3.11.12714
18594.3.11.128/2894.3.11.129 to 94.3.11.14294.3.11.14314
18694.3.11.144/2894.3.11.145 to 94.3.11.15894.3.11.15914
18794.3.11.160/2894.3.11.161 to 94.3.11.17494.3.11.17514
18894.3.11.176/2894.3.11.177 to 94.3.11.19094.3.11.19114
18994.3.11.192/2894.3.11.193 to 94.3.11.20694.3.11.20714
19094.3.11.208/2894.3.11.209 to 94.3.11.22294.3.11.22314
19194.3.11.224/2894.3.11.225 to 94.3.11.23894.3.11.23914
19294.3.11.240/2894.3.11.241 to 94.3.11.25494.3.11.25514
19394.3.12.0/2894.3.12.1 to 94.3.12.1494.3.12.1514
19494.3.12.16/2894.3.12.17 to 94.3.12.3094.3.12.3114
19594.3.12.32/2894.3.12.33 to 94.3.12.4694.3.12.4714
19694.3.12.48/2894.3.12.49 to 94.3.12.6294.3.12.6314
19794.3.12.64/2894.3.12.65 to 94.3.12.7894.3.12.7914
19894.3.12.80/2894.3.12.81 to 94.3.12.9494.3.12.9514
19994.3.12.96/2894.3.12.97 to 94.3.12.11094.3.12.11114
20094.3.12.112/2894.3.12.113 to 94.3.12.12694.3.12.12714
20194.3.12.128/2894.3.12.129 to 94.3.12.14294.3.12.14314
20294.3.12.144/2894.3.12.145 to 94.3.12.15894.3.12.15914
20394.3.12.160/2894.3.12.161 to 94.3.12.17494.3.12.17514
20494.3.12.176/2894.3.12.177 to 94.3.12.19094.3.12.19114
20594.3.12.192/2894.3.12.193 to 94.3.12.20694.3.12.20714
20694.3.12.208/2894.3.12.209 to 94.3.12.22294.3.12.22314
20794.3.12.224/2894.3.12.225 to 94.3.12.23894.3.12.23914
20894.3.12.240/2894.3.12.241 to 94.3.12.25494.3.12.25514
20994.3.13.0/2894.3.13.1 to 94.3.13.1494.3.13.1514
21094.3.13.16/2894.3.13.17 to 94.3.13.3094.3.13.3114
21194.3.13.32/2894.3.13.33 to 94.3.13.4694.3.13.4714
21294.3.13.48/2894.3.13.49 to 94.3.13.6294.3.13.6314
21394.3.13.64/2894.3.13.65 to 94.3.13.7894.3.13.7914
21494.3.13.80/2894.3.13.81 to 94.3.13.9494.3.13.9514
21594.3.13.96/2894.3.13.97 to 94.3.13.11094.3.13.11114
21694.3.13.112/2894.3.13.113 to 94.3.13.12694.3.13.12714
21794.3.13.128/2894.3.13.129 to 94.3.13.14294.3.13.14314
21894.3.13.144/2894.3.13.145 to 94.3.13.15894.3.13.15914
21994.3.13.160/2894.3.13.161 to 94.3.13.17494.3.13.17514
22094.3.13.176/2894.3.13.177 to 94.3.13.19094.3.13.19114
22194.3.13.192/2894.3.13.193 to 94.3.13.20694.3.13.20714
22294.3.13.208/2894.3.13.209 to 94.3.13.22294.3.13.22314
22394.3.13.224/2894.3.13.225 to 94.3.13.23894.3.13.23914
22494.3.13.240/2894.3.13.241 to 94.3.13.25494.3.13.25514
22594.3.14.0/2894.3.14.1 to 94.3.14.1494.3.14.1514
22694.3.14.16/2894.3.14.17 to 94.3.14.3094.3.14.3114
22794.3.14.32/2894.3.14.33 to 94.3.14.4694.3.14.4714
22894.3.14.48/2894.3.14.49 to 94.3.14.6294.3.14.6314
22994.3.14.64/2894.3.14.65 to 94.3.14.7894.3.14.7914
23094.3.14.80/2894.3.14.81 to 94.3.14.9494.3.14.9514
23194.3.14.96/2894.3.14.97 to 94.3.14.11094.3.14.11114
23294.3.14.112/2894.3.14.113 to 94.3.14.12694.3.14.12714
23394.3.14.128/2894.3.14.129 to 94.3.14.14294.3.14.14314
23494.3.14.144/2894.3.14.145 to 94.3.14.15894.3.14.15914
23594.3.14.160/2894.3.14.161 to 94.3.14.17494.3.14.17514
23694.3.14.176/2894.3.14.177 to 94.3.14.19094.3.14.19114
23794.3.14.192/2894.3.14.193 to 94.3.14.20694.3.14.20714
23894.3.14.208/2894.3.14.209 to 94.3.14.22294.3.14.22314
23994.3.14.224/2894.3.14.225 to 94.3.14.23894.3.14.23914
24094.3.14.240/2894.3.14.241 to 94.3.14.25494.3.14.25514
24194.3.15.0/2894.3.15.1 to 94.3.15.1494.3.15.1514
24294.3.15.16/2894.3.15.17 to 94.3.15.3094.3.15.3114
24394.3.15.32/2894.3.15.33 to 94.3.15.4694.3.15.4714
24494.3.15.48/2894.3.15.49 to 94.3.15.6294.3.15.6314
24594.3.15.64/2894.3.15.65 to 94.3.15.7894.3.15.7914
24694.3.15.80/2894.3.15.81 to 94.3.15.9494.3.15.9514
24794.3.15.96/2894.3.15.97 to 94.3.15.11094.3.15.11114
24894.3.15.112/2894.3.15.113 to 94.3.15.12694.3.15.12714
24994.3.15.128/2894.3.15.129 to 94.3.15.14294.3.15.14314
25094.3.15.144/2894.3.15.145 to 94.3.15.15894.3.15.15914
25194.3.15.160/2894.3.15.161 to 94.3.15.17494.3.15.17514
25294.3.15.176/2894.3.15.177 to 94.3.15.19094.3.15.19114
25394.3.15.192/2894.3.15.193 to 94.3.15.20694.3.15.20714
25494.3.15.208/2894.3.15.209 to 94.3.15.22294.3.15.22314
25594.3.15.224/2894.3.15.225 to 94.3.15.23894.3.15.23914
25694.3.15.240/2894.3.15.241 to 94.3.15.25494.3.15.25514

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