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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.

Network1.167.0.0/17
Usable hosts32,766
Subnet mask255.255.128.0
Addresses32,768
Network address
1.167.0.0
Broadcast address
1.167.127.255
First usable
1.167.0.1
Last usable
1.167.127.254
Usable hosts
32,766 (32,768 less the network and broadcast addresses)
Subnet mask
255.255.128.0
Wildcard mask
0.0.127.255 (Cisco ACLs, OSPF)
Prefix length
/17
Type
Public public
Old class
A (default /8)
As numbers
Hex 01A70000 · Integer 27721728 to 27754495
Reverse DNS zones
0.167.1.in-addr.arpa
1.167.1.in-addr.arpa
2.167.1.in-addr.arpa
3.167.1.in-addr.arpa
4.167.1.in-addr.arpa
5.167.1.in-addr.arpa
6.167.1.in-addr.arpa
7.167.1.in-addr.arpa
8.167.1.in-addr.arpa
9.167.1.in-addr.arpa
10.167.1.in-addr.arpa
11.167.1.in-addr.arpa
12.167.1.in-addr.arpa
13.167.1.in-addr.arpa
14.167.1.in-addr.arpa
15.167.1.in-addr.arpa
and 112 more
/17 is not on a 8-bit boundary, so it takes 128 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00000001.10100111.00000000.000000001.167.0.0
Subnet mask11111111.11111111.10000000.00000000255.255.128.0
Network00000001.10100111.00000000.000000001.167.0.0
Broadcast00000001.10100111.01111111.111111111.167.127.255
Split into smaller subnets/28

1.167.0.0/17 makes 2,048 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
11.167.0.0/281.167.0.1 to 1.167.0.141.167.0.1514
21.167.0.16/281.167.0.17 to 1.167.0.301.167.0.3114
31.167.0.32/281.167.0.33 to 1.167.0.461.167.0.4714
41.167.0.48/281.167.0.49 to 1.167.0.621.167.0.6314
51.167.0.64/281.167.0.65 to 1.167.0.781.167.0.7914
61.167.0.80/281.167.0.81 to 1.167.0.941.167.0.9514
71.167.0.96/281.167.0.97 to 1.167.0.1101.167.0.11114
81.167.0.112/281.167.0.113 to 1.167.0.1261.167.0.12714
91.167.0.128/281.167.0.129 to 1.167.0.1421.167.0.14314
101.167.0.144/281.167.0.145 to 1.167.0.1581.167.0.15914
111.167.0.160/281.167.0.161 to 1.167.0.1741.167.0.17514
121.167.0.176/281.167.0.177 to 1.167.0.1901.167.0.19114
131.167.0.192/281.167.0.193 to 1.167.0.2061.167.0.20714
141.167.0.208/281.167.0.209 to 1.167.0.2221.167.0.22314
151.167.0.224/281.167.0.225 to 1.167.0.2381.167.0.23914
161.167.0.240/281.167.0.241 to 1.167.0.2541.167.0.25514
171.167.1.0/281.167.1.1 to 1.167.1.141.167.1.1514
181.167.1.16/281.167.1.17 to 1.167.1.301.167.1.3114
191.167.1.32/281.167.1.33 to 1.167.1.461.167.1.4714
201.167.1.48/281.167.1.49 to 1.167.1.621.167.1.6314
211.167.1.64/281.167.1.65 to 1.167.1.781.167.1.7914
221.167.1.80/281.167.1.81 to 1.167.1.941.167.1.9514
231.167.1.96/281.167.1.97 to 1.167.1.1101.167.1.11114
241.167.1.112/281.167.1.113 to 1.167.1.1261.167.1.12714
251.167.1.128/281.167.1.129 to 1.167.1.1421.167.1.14314
261.167.1.144/281.167.1.145 to 1.167.1.1581.167.1.15914
271.167.1.160/281.167.1.161 to 1.167.1.1741.167.1.17514
281.167.1.176/281.167.1.177 to 1.167.1.1901.167.1.19114
291.167.1.192/281.167.1.193 to 1.167.1.2061.167.1.20714
301.167.1.208/281.167.1.209 to 1.167.1.2221.167.1.22314
311.167.1.224/281.167.1.225 to 1.167.1.2381.167.1.23914
321.167.1.240/281.167.1.241 to 1.167.1.2541.167.1.25514
331.167.2.0/281.167.2.1 to 1.167.2.141.167.2.1514
341.167.2.16/281.167.2.17 to 1.167.2.301.167.2.3114
351.167.2.32/281.167.2.33 to 1.167.2.461.167.2.4714
361.167.2.48/281.167.2.49 to 1.167.2.621.167.2.6314
371.167.2.64/281.167.2.65 to 1.167.2.781.167.2.7914
381.167.2.80/281.167.2.81 to 1.167.2.941.167.2.9514
391.167.2.96/281.167.2.97 to 1.167.2.1101.167.2.11114
401.167.2.112/281.167.2.113 to 1.167.2.1261.167.2.12714
411.167.2.128/281.167.2.129 to 1.167.2.1421.167.2.14314
421.167.2.144/281.167.2.145 to 1.167.2.1581.167.2.15914
431.167.2.160/281.167.2.161 to 1.167.2.1741.167.2.17514
441.167.2.176/281.167.2.177 to 1.167.2.1901.167.2.19114
451.167.2.192/281.167.2.193 to 1.167.2.2061.167.2.20714
461.167.2.208/281.167.2.209 to 1.167.2.2221.167.2.22314
471.167.2.224/281.167.2.225 to 1.167.2.2381.167.2.23914
481.167.2.240/281.167.2.241 to 1.167.2.2541.167.2.25514
491.167.3.0/281.167.3.1 to 1.167.3.141.167.3.1514
501.167.3.16/281.167.3.17 to 1.167.3.301.167.3.3114
511.167.3.32/281.167.3.33 to 1.167.3.461.167.3.4714
521.167.3.48/281.167.3.49 to 1.167.3.621.167.3.6314
531.167.3.64/281.167.3.65 to 1.167.3.781.167.3.7914
541.167.3.80/281.167.3.81 to 1.167.3.941.167.3.9514
551.167.3.96/281.167.3.97 to 1.167.3.1101.167.3.11114
561.167.3.112/281.167.3.113 to 1.167.3.1261.167.3.12714
571.167.3.128/281.167.3.129 to 1.167.3.1421.167.3.14314
581.167.3.144/281.167.3.145 to 1.167.3.1581.167.3.15914
591.167.3.160/281.167.3.161 to 1.167.3.1741.167.3.17514
601.167.3.176/281.167.3.177 to 1.167.3.1901.167.3.19114
611.167.3.192/281.167.3.193 to 1.167.3.2061.167.3.20714
621.167.3.208/281.167.3.209 to 1.167.3.2221.167.3.22314
631.167.3.224/281.167.3.225 to 1.167.3.2381.167.3.23914
641.167.3.240/281.167.3.241 to 1.167.3.2541.167.3.25514
651.167.4.0/281.167.4.1 to 1.167.4.141.167.4.1514
661.167.4.16/281.167.4.17 to 1.167.4.301.167.4.3114
671.167.4.32/281.167.4.33 to 1.167.4.461.167.4.4714
681.167.4.48/281.167.4.49 to 1.167.4.621.167.4.6314
691.167.4.64/281.167.4.65 to 1.167.4.781.167.4.7914
701.167.4.80/281.167.4.81 to 1.167.4.941.167.4.9514
711.167.4.96/281.167.4.97 to 1.167.4.1101.167.4.11114
721.167.4.112/281.167.4.113 to 1.167.4.1261.167.4.12714
731.167.4.128/281.167.4.129 to 1.167.4.1421.167.4.14314
741.167.4.144/281.167.4.145 to 1.167.4.1581.167.4.15914
751.167.4.160/281.167.4.161 to 1.167.4.1741.167.4.17514
761.167.4.176/281.167.4.177 to 1.167.4.1901.167.4.19114
771.167.4.192/281.167.4.193 to 1.167.4.2061.167.4.20714
781.167.4.208/281.167.4.209 to 1.167.4.2221.167.4.22314
791.167.4.224/281.167.4.225 to 1.167.4.2381.167.4.23914
801.167.4.240/281.167.4.241 to 1.167.4.2541.167.4.25514
811.167.5.0/281.167.5.1 to 1.167.5.141.167.5.1514
821.167.5.16/281.167.5.17 to 1.167.5.301.167.5.3114
831.167.5.32/281.167.5.33 to 1.167.5.461.167.5.4714
841.167.5.48/281.167.5.49 to 1.167.5.621.167.5.6314
851.167.5.64/281.167.5.65 to 1.167.5.781.167.5.7914
861.167.5.80/281.167.5.81 to 1.167.5.941.167.5.9514
871.167.5.96/281.167.5.97 to 1.167.5.1101.167.5.11114
881.167.5.112/281.167.5.113 to 1.167.5.1261.167.5.12714
891.167.5.128/281.167.5.129 to 1.167.5.1421.167.5.14314
901.167.5.144/281.167.5.145 to 1.167.5.1581.167.5.15914
911.167.5.160/281.167.5.161 to 1.167.5.1741.167.5.17514
921.167.5.176/281.167.5.177 to 1.167.5.1901.167.5.19114
931.167.5.192/281.167.5.193 to 1.167.5.2061.167.5.20714
941.167.5.208/281.167.5.209 to 1.167.5.2221.167.5.22314
951.167.5.224/281.167.5.225 to 1.167.5.2381.167.5.23914
961.167.5.240/281.167.5.241 to 1.167.5.2541.167.5.25514
971.167.6.0/281.167.6.1 to 1.167.6.141.167.6.1514
981.167.6.16/281.167.6.17 to 1.167.6.301.167.6.3114
991.167.6.32/281.167.6.33 to 1.167.6.461.167.6.4714
1001.167.6.48/281.167.6.49 to 1.167.6.621.167.6.6314
1011.167.6.64/281.167.6.65 to 1.167.6.781.167.6.7914
1021.167.6.80/281.167.6.81 to 1.167.6.941.167.6.9514
1031.167.6.96/281.167.6.97 to 1.167.6.1101.167.6.11114
1041.167.6.112/281.167.6.113 to 1.167.6.1261.167.6.12714
1051.167.6.128/281.167.6.129 to 1.167.6.1421.167.6.14314
1061.167.6.144/281.167.6.145 to 1.167.6.1581.167.6.15914
1071.167.6.160/281.167.6.161 to 1.167.6.1741.167.6.17514
1081.167.6.176/281.167.6.177 to 1.167.6.1901.167.6.19114
1091.167.6.192/281.167.6.193 to 1.167.6.2061.167.6.20714
1101.167.6.208/281.167.6.209 to 1.167.6.2221.167.6.22314
1111.167.6.224/281.167.6.225 to 1.167.6.2381.167.6.23914
1121.167.6.240/281.167.6.241 to 1.167.6.2541.167.6.25514
1131.167.7.0/281.167.7.1 to 1.167.7.141.167.7.1514
1141.167.7.16/281.167.7.17 to 1.167.7.301.167.7.3114
1151.167.7.32/281.167.7.33 to 1.167.7.461.167.7.4714
1161.167.7.48/281.167.7.49 to 1.167.7.621.167.7.6314
1171.167.7.64/281.167.7.65 to 1.167.7.781.167.7.7914
1181.167.7.80/281.167.7.81 to 1.167.7.941.167.7.9514
1191.167.7.96/281.167.7.97 to 1.167.7.1101.167.7.11114
1201.167.7.112/281.167.7.113 to 1.167.7.1261.167.7.12714
1211.167.7.128/281.167.7.129 to 1.167.7.1421.167.7.14314
1221.167.7.144/281.167.7.145 to 1.167.7.1581.167.7.15914
1231.167.7.160/281.167.7.161 to 1.167.7.1741.167.7.17514
1241.167.7.176/281.167.7.177 to 1.167.7.1901.167.7.19114
1251.167.7.192/281.167.7.193 to 1.167.7.2061.167.7.20714
1261.167.7.208/281.167.7.209 to 1.167.7.2221.167.7.22314
1271.167.7.224/281.167.7.225 to 1.167.7.2381.167.7.23914
1281.167.7.240/281.167.7.241 to 1.167.7.2541.167.7.25514
1291.167.8.0/281.167.8.1 to 1.167.8.141.167.8.1514
1301.167.8.16/281.167.8.17 to 1.167.8.301.167.8.3114
1311.167.8.32/281.167.8.33 to 1.167.8.461.167.8.4714
1321.167.8.48/281.167.8.49 to 1.167.8.621.167.8.6314
1331.167.8.64/281.167.8.65 to 1.167.8.781.167.8.7914
1341.167.8.80/281.167.8.81 to 1.167.8.941.167.8.9514
1351.167.8.96/281.167.8.97 to 1.167.8.1101.167.8.11114
1361.167.8.112/281.167.8.113 to 1.167.8.1261.167.8.12714
1371.167.8.128/281.167.8.129 to 1.167.8.1421.167.8.14314
1381.167.8.144/281.167.8.145 to 1.167.8.1581.167.8.15914
1391.167.8.160/281.167.8.161 to 1.167.8.1741.167.8.17514
1401.167.8.176/281.167.8.177 to 1.167.8.1901.167.8.19114
1411.167.8.192/281.167.8.193 to 1.167.8.2061.167.8.20714
1421.167.8.208/281.167.8.209 to 1.167.8.2221.167.8.22314
1431.167.8.224/281.167.8.225 to 1.167.8.2381.167.8.23914
1441.167.8.240/281.167.8.241 to 1.167.8.2541.167.8.25514
1451.167.9.0/281.167.9.1 to 1.167.9.141.167.9.1514
1461.167.9.16/281.167.9.17 to 1.167.9.301.167.9.3114
1471.167.9.32/281.167.9.33 to 1.167.9.461.167.9.4714
1481.167.9.48/281.167.9.49 to 1.167.9.621.167.9.6314
1491.167.9.64/281.167.9.65 to 1.167.9.781.167.9.7914
1501.167.9.80/281.167.9.81 to 1.167.9.941.167.9.9514
1511.167.9.96/281.167.9.97 to 1.167.9.1101.167.9.11114
1521.167.9.112/281.167.9.113 to 1.167.9.1261.167.9.12714
1531.167.9.128/281.167.9.129 to 1.167.9.1421.167.9.14314
1541.167.9.144/281.167.9.145 to 1.167.9.1581.167.9.15914
1551.167.9.160/281.167.9.161 to 1.167.9.1741.167.9.17514
1561.167.9.176/281.167.9.177 to 1.167.9.1901.167.9.19114
1571.167.9.192/281.167.9.193 to 1.167.9.2061.167.9.20714
1581.167.9.208/281.167.9.209 to 1.167.9.2221.167.9.22314
1591.167.9.224/281.167.9.225 to 1.167.9.2381.167.9.23914
1601.167.9.240/281.167.9.241 to 1.167.9.2541.167.9.25514
1611.167.10.0/281.167.10.1 to 1.167.10.141.167.10.1514
1621.167.10.16/281.167.10.17 to 1.167.10.301.167.10.3114
1631.167.10.32/281.167.10.33 to 1.167.10.461.167.10.4714
1641.167.10.48/281.167.10.49 to 1.167.10.621.167.10.6314
1651.167.10.64/281.167.10.65 to 1.167.10.781.167.10.7914
1661.167.10.80/281.167.10.81 to 1.167.10.941.167.10.9514
1671.167.10.96/281.167.10.97 to 1.167.10.1101.167.10.11114
1681.167.10.112/281.167.10.113 to 1.167.10.1261.167.10.12714
1691.167.10.128/281.167.10.129 to 1.167.10.1421.167.10.14314
1701.167.10.144/281.167.10.145 to 1.167.10.1581.167.10.15914
1711.167.10.160/281.167.10.161 to 1.167.10.1741.167.10.17514
1721.167.10.176/281.167.10.177 to 1.167.10.1901.167.10.19114
1731.167.10.192/281.167.10.193 to 1.167.10.2061.167.10.20714
1741.167.10.208/281.167.10.209 to 1.167.10.2221.167.10.22314
1751.167.10.224/281.167.10.225 to 1.167.10.2381.167.10.23914
1761.167.10.240/281.167.10.241 to 1.167.10.2541.167.10.25514
1771.167.11.0/281.167.11.1 to 1.167.11.141.167.11.1514
1781.167.11.16/281.167.11.17 to 1.167.11.301.167.11.3114
1791.167.11.32/281.167.11.33 to 1.167.11.461.167.11.4714
1801.167.11.48/281.167.11.49 to 1.167.11.621.167.11.6314
1811.167.11.64/281.167.11.65 to 1.167.11.781.167.11.7914
1821.167.11.80/281.167.11.81 to 1.167.11.941.167.11.9514
1831.167.11.96/281.167.11.97 to 1.167.11.1101.167.11.11114
1841.167.11.112/281.167.11.113 to 1.167.11.1261.167.11.12714
1851.167.11.128/281.167.11.129 to 1.167.11.1421.167.11.14314
1861.167.11.144/281.167.11.145 to 1.167.11.1581.167.11.15914
1871.167.11.160/281.167.11.161 to 1.167.11.1741.167.11.17514
1881.167.11.176/281.167.11.177 to 1.167.11.1901.167.11.19114
1891.167.11.192/281.167.11.193 to 1.167.11.2061.167.11.20714
1901.167.11.208/281.167.11.209 to 1.167.11.2221.167.11.22314
1911.167.11.224/281.167.11.225 to 1.167.11.2381.167.11.23914
1921.167.11.240/281.167.11.241 to 1.167.11.2541.167.11.25514
1931.167.12.0/281.167.12.1 to 1.167.12.141.167.12.1514
1941.167.12.16/281.167.12.17 to 1.167.12.301.167.12.3114
1951.167.12.32/281.167.12.33 to 1.167.12.461.167.12.4714
1961.167.12.48/281.167.12.49 to 1.167.12.621.167.12.6314
1971.167.12.64/281.167.12.65 to 1.167.12.781.167.12.7914
1981.167.12.80/281.167.12.81 to 1.167.12.941.167.12.9514
1991.167.12.96/281.167.12.97 to 1.167.12.1101.167.12.11114
2001.167.12.112/281.167.12.113 to 1.167.12.1261.167.12.12714
2011.167.12.128/281.167.12.129 to 1.167.12.1421.167.12.14314
2021.167.12.144/281.167.12.145 to 1.167.12.1581.167.12.15914
2031.167.12.160/281.167.12.161 to 1.167.12.1741.167.12.17514
2041.167.12.176/281.167.12.177 to 1.167.12.1901.167.12.19114
2051.167.12.192/281.167.12.193 to 1.167.12.2061.167.12.20714
2061.167.12.208/281.167.12.209 to 1.167.12.2221.167.12.22314
2071.167.12.224/281.167.12.225 to 1.167.12.2381.167.12.23914
2081.167.12.240/281.167.12.241 to 1.167.12.2541.167.12.25514
2091.167.13.0/281.167.13.1 to 1.167.13.141.167.13.1514
2101.167.13.16/281.167.13.17 to 1.167.13.301.167.13.3114
2111.167.13.32/281.167.13.33 to 1.167.13.461.167.13.4714
2121.167.13.48/281.167.13.49 to 1.167.13.621.167.13.6314
2131.167.13.64/281.167.13.65 to 1.167.13.781.167.13.7914
2141.167.13.80/281.167.13.81 to 1.167.13.941.167.13.9514
2151.167.13.96/281.167.13.97 to 1.167.13.1101.167.13.11114
2161.167.13.112/281.167.13.113 to 1.167.13.1261.167.13.12714
2171.167.13.128/281.167.13.129 to 1.167.13.1421.167.13.14314
2181.167.13.144/281.167.13.145 to 1.167.13.1581.167.13.15914
2191.167.13.160/281.167.13.161 to 1.167.13.1741.167.13.17514
2201.167.13.176/281.167.13.177 to 1.167.13.1901.167.13.19114
2211.167.13.192/281.167.13.193 to 1.167.13.2061.167.13.20714
2221.167.13.208/281.167.13.209 to 1.167.13.2221.167.13.22314
2231.167.13.224/281.167.13.225 to 1.167.13.2381.167.13.23914
2241.167.13.240/281.167.13.241 to 1.167.13.2541.167.13.25514
2251.167.14.0/281.167.14.1 to 1.167.14.141.167.14.1514
2261.167.14.16/281.167.14.17 to 1.167.14.301.167.14.3114
2271.167.14.32/281.167.14.33 to 1.167.14.461.167.14.4714
2281.167.14.48/281.167.14.49 to 1.167.14.621.167.14.6314
2291.167.14.64/281.167.14.65 to 1.167.14.781.167.14.7914
2301.167.14.80/281.167.14.81 to 1.167.14.941.167.14.9514
2311.167.14.96/281.167.14.97 to 1.167.14.1101.167.14.11114
2321.167.14.112/281.167.14.113 to 1.167.14.1261.167.14.12714
2331.167.14.128/281.167.14.129 to 1.167.14.1421.167.14.14314
2341.167.14.144/281.167.14.145 to 1.167.14.1581.167.14.15914
2351.167.14.160/281.167.14.161 to 1.167.14.1741.167.14.17514
2361.167.14.176/281.167.14.177 to 1.167.14.1901.167.14.19114
2371.167.14.192/281.167.14.193 to 1.167.14.2061.167.14.20714
2381.167.14.208/281.167.14.209 to 1.167.14.2221.167.14.22314
2391.167.14.224/281.167.14.225 to 1.167.14.2381.167.14.23914
2401.167.14.240/281.167.14.241 to 1.167.14.2541.167.14.25514
2411.167.15.0/281.167.15.1 to 1.167.15.141.167.15.1514
2421.167.15.16/281.167.15.17 to 1.167.15.301.167.15.3114
2431.167.15.32/281.167.15.33 to 1.167.15.461.167.15.4714
2441.167.15.48/281.167.15.49 to 1.167.15.621.167.15.6314
2451.167.15.64/281.167.15.65 to 1.167.15.781.167.15.7914
2461.167.15.80/281.167.15.81 to 1.167.15.941.167.15.9514
2471.167.15.96/281.167.15.97 to 1.167.15.1101.167.15.11114
2481.167.15.112/281.167.15.113 to 1.167.15.1261.167.15.12714
2491.167.15.128/281.167.15.129 to 1.167.15.1421.167.15.14314
2501.167.15.144/281.167.15.145 to 1.167.15.1581.167.15.15914
2511.167.15.160/281.167.15.161 to 1.167.15.1741.167.15.17514
2521.167.15.176/281.167.15.177 to 1.167.15.1901.167.15.19114
2531.167.15.192/281.167.15.193 to 1.167.15.2061.167.15.20714
2541.167.15.208/281.167.15.209 to 1.167.15.2221.167.15.22314
2551.167.15.224/281.167.15.225 to 1.167.15.2381.167.15.23914
2561.167.15.240/281.167.15.241 to 1.167.15.2541.167.15.25514

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