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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.

Network4.78.0.0/17
Usable hosts32,766
Subnet mask255.255.128.0
Addresses32,768
Network address
4.78.0.0
Broadcast address
4.78.127.255
First usable
4.78.0.1
Last usable
4.78.127.254
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 044E0000 · Integer 72220672 to 72253439
Reverse DNS zones
0.78.4.in-addr.arpa
1.78.4.in-addr.arpa
2.78.4.in-addr.arpa
3.78.4.in-addr.arpa
4.78.4.in-addr.arpa
5.78.4.in-addr.arpa
6.78.4.in-addr.arpa
7.78.4.in-addr.arpa
8.78.4.in-addr.arpa
9.78.4.in-addr.arpa
10.78.4.in-addr.arpa
11.78.4.in-addr.arpa
12.78.4.in-addr.arpa
13.78.4.in-addr.arpa
14.78.4.in-addr.arpa
15.78.4.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
Address00000100.01001110.00000000.000000004.78.0.0
Subnet mask11111111.11111111.10000000.00000000255.255.128.0
Network00000100.01001110.00000000.000000004.78.0.0
Broadcast00000100.01001110.01111111.111111114.78.127.255
Split into smaller subnets/27

4.78.0.0/17 makes 1,024 subnets of /27; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
14.78.0.0/274.78.0.1 to 4.78.0.304.78.0.3130
24.78.0.32/274.78.0.33 to 4.78.0.624.78.0.6330
34.78.0.64/274.78.0.65 to 4.78.0.944.78.0.9530
44.78.0.96/274.78.0.97 to 4.78.0.1264.78.0.12730
54.78.0.128/274.78.0.129 to 4.78.0.1584.78.0.15930
64.78.0.160/274.78.0.161 to 4.78.0.1904.78.0.19130
74.78.0.192/274.78.0.193 to 4.78.0.2224.78.0.22330
84.78.0.224/274.78.0.225 to 4.78.0.2544.78.0.25530
94.78.1.0/274.78.1.1 to 4.78.1.304.78.1.3130
104.78.1.32/274.78.1.33 to 4.78.1.624.78.1.6330
114.78.1.64/274.78.1.65 to 4.78.1.944.78.1.9530
124.78.1.96/274.78.1.97 to 4.78.1.1264.78.1.12730
134.78.1.128/274.78.1.129 to 4.78.1.1584.78.1.15930
144.78.1.160/274.78.1.161 to 4.78.1.1904.78.1.19130
154.78.1.192/274.78.1.193 to 4.78.1.2224.78.1.22330
164.78.1.224/274.78.1.225 to 4.78.1.2544.78.1.25530
174.78.2.0/274.78.2.1 to 4.78.2.304.78.2.3130
184.78.2.32/274.78.2.33 to 4.78.2.624.78.2.6330
194.78.2.64/274.78.2.65 to 4.78.2.944.78.2.9530
204.78.2.96/274.78.2.97 to 4.78.2.1264.78.2.12730
214.78.2.128/274.78.2.129 to 4.78.2.1584.78.2.15930
224.78.2.160/274.78.2.161 to 4.78.2.1904.78.2.19130
234.78.2.192/274.78.2.193 to 4.78.2.2224.78.2.22330
244.78.2.224/274.78.2.225 to 4.78.2.2544.78.2.25530
254.78.3.0/274.78.3.1 to 4.78.3.304.78.3.3130
264.78.3.32/274.78.3.33 to 4.78.3.624.78.3.6330
274.78.3.64/274.78.3.65 to 4.78.3.944.78.3.9530
284.78.3.96/274.78.3.97 to 4.78.3.1264.78.3.12730
294.78.3.128/274.78.3.129 to 4.78.3.1584.78.3.15930
304.78.3.160/274.78.3.161 to 4.78.3.1904.78.3.19130
314.78.3.192/274.78.3.193 to 4.78.3.2224.78.3.22330
324.78.3.224/274.78.3.225 to 4.78.3.2544.78.3.25530
334.78.4.0/274.78.4.1 to 4.78.4.304.78.4.3130
344.78.4.32/274.78.4.33 to 4.78.4.624.78.4.6330
354.78.4.64/274.78.4.65 to 4.78.4.944.78.4.9530
364.78.4.96/274.78.4.97 to 4.78.4.1264.78.4.12730
374.78.4.128/274.78.4.129 to 4.78.4.1584.78.4.15930
384.78.4.160/274.78.4.161 to 4.78.4.1904.78.4.19130
394.78.4.192/274.78.4.193 to 4.78.4.2224.78.4.22330
404.78.4.224/274.78.4.225 to 4.78.4.2544.78.4.25530
414.78.5.0/274.78.5.1 to 4.78.5.304.78.5.3130
424.78.5.32/274.78.5.33 to 4.78.5.624.78.5.6330
434.78.5.64/274.78.5.65 to 4.78.5.944.78.5.9530
444.78.5.96/274.78.5.97 to 4.78.5.1264.78.5.12730
454.78.5.128/274.78.5.129 to 4.78.5.1584.78.5.15930
464.78.5.160/274.78.5.161 to 4.78.5.1904.78.5.19130
474.78.5.192/274.78.5.193 to 4.78.5.2224.78.5.22330
484.78.5.224/274.78.5.225 to 4.78.5.2544.78.5.25530
494.78.6.0/274.78.6.1 to 4.78.6.304.78.6.3130
504.78.6.32/274.78.6.33 to 4.78.6.624.78.6.6330
514.78.6.64/274.78.6.65 to 4.78.6.944.78.6.9530
524.78.6.96/274.78.6.97 to 4.78.6.1264.78.6.12730
534.78.6.128/274.78.6.129 to 4.78.6.1584.78.6.15930
544.78.6.160/274.78.6.161 to 4.78.6.1904.78.6.19130
554.78.6.192/274.78.6.193 to 4.78.6.2224.78.6.22330
564.78.6.224/274.78.6.225 to 4.78.6.2544.78.6.25530
574.78.7.0/274.78.7.1 to 4.78.7.304.78.7.3130
584.78.7.32/274.78.7.33 to 4.78.7.624.78.7.6330
594.78.7.64/274.78.7.65 to 4.78.7.944.78.7.9530
604.78.7.96/274.78.7.97 to 4.78.7.1264.78.7.12730
614.78.7.128/274.78.7.129 to 4.78.7.1584.78.7.15930
624.78.7.160/274.78.7.161 to 4.78.7.1904.78.7.19130
634.78.7.192/274.78.7.193 to 4.78.7.2224.78.7.22330
644.78.7.224/274.78.7.225 to 4.78.7.2544.78.7.25530
654.78.8.0/274.78.8.1 to 4.78.8.304.78.8.3130
664.78.8.32/274.78.8.33 to 4.78.8.624.78.8.6330
674.78.8.64/274.78.8.65 to 4.78.8.944.78.8.9530
684.78.8.96/274.78.8.97 to 4.78.8.1264.78.8.12730
694.78.8.128/274.78.8.129 to 4.78.8.1584.78.8.15930
704.78.8.160/274.78.8.161 to 4.78.8.1904.78.8.19130
714.78.8.192/274.78.8.193 to 4.78.8.2224.78.8.22330
724.78.8.224/274.78.8.225 to 4.78.8.2544.78.8.25530
734.78.9.0/274.78.9.1 to 4.78.9.304.78.9.3130
744.78.9.32/274.78.9.33 to 4.78.9.624.78.9.6330
754.78.9.64/274.78.9.65 to 4.78.9.944.78.9.9530
764.78.9.96/274.78.9.97 to 4.78.9.1264.78.9.12730
774.78.9.128/274.78.9.129 to 4.78.9.1584.78.9.15930
784.78.9.160/274.78.9.161 to 4.78.9.1904.78.9.19130
794.78.9.192/274.78.9.193 to 4.78.9.2224.78.9.22330
804.78.9.224/274.78.9.225 to 4.78.9.2544.78.9.25530
814.78.10.0/274.78.10.1 to 4.78.10.304.78.10.3130
824.78.10.32/274.78.10.33 to 4.78.10.624.78.10.6330
834.78.10.64/274.78.10.65 to 4.78.10.944.78.10.9530
844.78.10.96/274.78.10.97 to 4.78.10.1264.78.10.12730
854.78.10.128/274.78.10.129 to 4.78.10.1584.78.10.15930
864.78.10.160/274.78.10.161 to 4.78.10.1904.78.10.19130
874.78.10.192/274.78.10.193 to 4.78.10.2224.78.10.22330
884.78.10.224/274.78.10.225 to 4.78.10.2544.78.10.25530
894.78.11.0/274.78.11.1 to 4.78.11.304.78.11.3130
904.78.11.32/274.78.11.33 to 4.78.11.624.78.11.6330
914.78.11.64/274.78.11.65 to 4.78.11.944.78.11.9530
924.78.11.96/274.78.11.97 to 4.78.11.1264.78.11.12730
934.78.11.128/274.78.11.129 to 4.78.11.1584.78.11.15930
944.78.11.160/274.78.11.161 to 4.78.11.1904.78.11.19130
954.78.11.192/274.78.11.193 to 4.78.11.2224.78.11.22330
964.78.11.224/274.78.11.225 to 4.78.11.2544.78.11.25530
974.78.12.0/274.78.12.1 to 4.78.12.304.78.12.3130
984.78.12.32/274.78.12.33 to 4.78.12.624.78.12.6330
994.78.12.64/274.78.12.65 to 4.78.12.944.78.12.9530
1004.78.12.96/274.78.12.97 to 4.78.12.1264.78.12.12730
1014.78.12.128/274.78.12.129 to 4.78.12.1584.78.12.15930
1024.78.12.160/274.78.12.161 to 4.78.12.1904.78.12.19130
1034.78.12.192/274.78.12.193 to 4.78.12.2224.78.12.22330
1044.78.12.224/274.78.12.225 to 4.78.12.2544.78.12.25530
1054.78.13.0/274.78.13.1 to 4.78.13.304.78.13.3130
1064.78.13.32/274.78.13.33 to 4.78.13.624.78.13.6330
1074.78.13.64/274.78.13.65 to 4.78.13.944.78.13.9530
1084.78.13.96/274.78.13.97 to 4.78.13.1264.78.13.12730
1094.78.13.128/274.78.13.129 to 4.78.13.1584.78.13.15930
1104.78.13.160/274.78.13.161 to 4.78.13.1904.78.13.19130
1114.78.13.192/274.78.13.193 to 4.78.13.2224.78.13.22330
1124.78.13.224/274.78.13.225 to 4.78.13.2544.78.13.25530
1134.78.14.0/274.78.14.1 to 4.78.14.304.78.14.3130
1144.78.14.32/274.78.14.33 to 4.78.14.624.78.14.6330
1154.78.14.64/274.78.14.65 to 4.78.14.944.78.14.9530
1164.78.14.96/274.78.14.97 to 4.78.14.1264.78.14.12730
1174.78.14.128/274.78.14.129 to 4.78.14.1584.78.14.15930
1184.78.14.160/274.78.14.161 to 4.78.14.1904.78.14.19130
1194.78.14.192/274.78.14.193 to 4.78.14.2224.78.14.22330
1204.78.14.224/274.78.14.225 to 4.78.14.2544.78.14.25530
1214.78.15.0/274.78.15.1 to 4.78.15.304.78.15.3130
1224.78.15.32/274.78.15.33 to 4.78.15.624.78.15.6330
1234.78.15.64/274.78.15.65 to 4.78.15.944.78.15.9530
1244.78.15.96/274.78.15.97 to 4.78.15.1264.78.15.12730
1254.78.15.128/274.78.15.129 to 4.78.15.1584.78.15.15930
1264.78.15.160/274.78.15.161 to 4.78.15.1904.78.15.19130
1274.78.15.192/274.78.15.193 to 4.78.15.2224.78.15.22330
1284.78.15.224/274.78.15.225 to 4.78.15.2544.78.15.25530
1294.78.16.0/274.78.16.1 to 4.78.16.304.78.16.3130
1304.78.16.32/274.78.16.33 to 4.78.16.624.78.16.6330
1314.78.16.64/274.78.16.65 to 4.78.16.944.78.16.9530
1324.78.16.96/274.78.16.97 to 4.78.16.1264.78.16.12730
1334.78.16.128/274.78.16.129 to 4.78.16.1584.78.16.15930
1344.78.16.160/274.78.16.161 to 4.78.16.1904.78.16.19130
1354.78.16.192/274.78.16.193 to 4.78.16.2224.78.16.22330
1364.78.16.224/274.78.16.225 to 4.78.16.2544.78.16.25530
1374.78.17.0/274.78.17.1 to 4.78.17.304.78.17.3130
1384.78.17.32/274.78.17.33 to 4.78.17.624.78.17.6330
1394.78.17.64/274.78.17.65 to 4.78.17.944.78.17.9530
1404.78.17.96/274.78.17.97 to 4.78.17.1264.78.17.12730
1414.78.17.128/274.78.17.129 to 4.78.17.1584.78.17.15930
1424.78.17.160/274.78.17.161 to 4.78.17.1904.78.17.19130
1434.78.17.192/274.78.17.193 to 4.78.17.2224.78.17.22330
1444.78.17.224/274.78.17.225 to 4.78.17.2544.78.17.25530
1454.78.18.0/274.78.18.1 to 4.78.18.304.78.18.3130
1464.78.18.32/274.78.18.33 to 4.78.18.624.78.18.6330
1474.78.18.64/274.78.18.65 to 4.78.18.944.78.18.9530
1484.78.18.96/274.78.18.97 to 4.78.18.1264.78.18.12730
1494.78.18.128/274.78.18.129 to 4.78.18.1584.78.18.15930
1504.78.18.160/274.78.18.161 to 4.78.18.1904.78.18.19130
1514.78.18.192/274.78.18.193 to 4.78.18.2224.78.18.22330
1524.78.18.224/274.78.18.225 to 4.78.18.2544.78.18.25530
1534.78.19.0/274.78.19.1 to 4.78.19.304.78.19.3130
1544.78.19.32/274.78.19.33 to 4.78.19.624.78.19.6330
1554.78.19.64/274.78.19.65 to 4.78.19.944.78.19.9530
1564.78.19.96/274.78.19.97 to 4.78.19.1264.78.19.12730
1574.78.19.128/274.78.19.129 to 4.78.19.1584.78.19.15930
1584.78.19.160/274.78.19.161 to 4.78.19.1904.78.19.19130
1594.78.19.192/274.78.19.193 to 4.78.19.2224.78.19.22330
1604.78.19.224/274.78.19.225 to 4.78.19.2544.78.19.25530
1614.78.20.0/274.78.20.1 to 4.78.20.304.78.20.3130
1624.78.20.32/274.78.20.33 to 4.78.20.624.78.20.6330
1634.78.20.64/274.78.20.65 to 4.78.20.944.78.20.9530
1644.78.20.96/274.78.20.97 to 4.78.20.1264.78.20.12730
1654.78.20.128/274.78.20.129 to 4.78.20.1584.78.20.15930
1664.78.20.160/274.78.20.161 to 4.78.20.1904.78.20.19130
1674.78.20.192/274.78.20.193 to 4.78.20.2224.78.20.22330
1684.78.20.224/274.78.20.225 to 4.78.20.2544.78.20.25530
1694.78.21.0/274.78.21.1 to 4.78.21.304.78.21.3130
1704.78.21.32/274.78.21.33 to 4.78.21.624.78.21.6330
1714.78.21.64/274.78.21.65 to 4.78.21.944.78.21.9530
1724.78.21.96/274.78.21.97 to 4.78.21.1264.78.21.12730
1734.78.21.128/274.78.21.129 to 4.78.21.1584.78.21.15930
1744.78.21.160/274.78.21.161 to 4.78.21.1904.78.21.19130
1754.78.21.192/274.78.21.193 to 4.78.21.2224.78.21.22330
1764.78.21.224/274.78.21.225 to 4.78.21.2544.78.21.25530
1774.78.22.0/274.78.22.1 to 4.78.22.304.78.22.3130
1784.78.22.32/274.78.22.33 to 4.78.22.624.78.22.6330
1794.78.22.64/274.78.22.65 to 4.78.22.944.78.22.9530
1804.78.22.96/274.78.22.97 to 4.78.22.1264.78.22.12730
1814.78.22.128/274.78.22.129 to 4.78.22.1584.78.22.15930
1824.78.22.160/274.78.22.161 to 4.78.22.1904.78.22.19130
1834.78.22.192/274.78.22.193 to 4.78.22.2224.78.22.22330
1844.78.22.224/274.78.22.225 to 4.78.22.2544.78.22.25530
1854.78.23.0/274.78.23.1 to 4.78.23.304.78.23.3130
1864.78.23.32/274.78.23.33 to 4.78.23.624.78.23.6330
1874.78.23.64/274.78.23.65 to 4.78.23.944.78.23.9530
1884.78.23.96/274.78.23.97 to 4.78.23.1264.78.23.12730
1894.78.23.128/274.78.23.129 to 4.78.23.1584.78.23.15930
1904.78.23.160/274.78.23.161 to 4.78.23.1904.78.23.19130
1914.78.23.192/274.78.23.193 to 4.78.23.2224.78.23.22330
1924.78.23.224/274.78.23.225 to 4.78.23.2544.78.23.25530
1934.78.24.0/274.78.24.1 to 4.78.24.304.78.24.3130
1944.78.24.32/274.78.24.33 to 4.78.24.624.78.24.6330
1954.78.24.64/274.78.24.65 to 4.78.24.944.78.24.9530
1964.78.24.96/274.78.24.97 to 4.78.24.1264.78.24.12730
1974.78.24.128/274.78.24.129 to 4.78.24.1584.78.24.15930
1984.78.24.160/274.78.24.161 to 4.78.24.1904.78.24.19130
1994.78.24.192/274.78.24.193 to 4.78.24.2224.78.24.22330
2004.78.24.224/274.78.24.225 to 4.78.24.2544.78.24.25530
2014.78.25.0/274.78.25.1 to 4.78.25.304.78.25.3130
2024.78.25.32/274.78.25.33 to 4.78.25.624.78.25.6330
2034.78.25.64/274.78.25.65 to 4.78.25.944.78.25.9530
2044.78.25.96/274.78.25.97 to 4.78.25.1264.78.25.12730
2054.78.25.128/274.78.25.129 to 4.78.25.1584.78.25.15930
2064.78.25.160/274.78.25.161 to 4.78.25.1904.78.25.19130
2074.78.25.192/274.78.25.193 to 4.78.25.2224.78.25.22330
2084.78.25.224/274.78.25.225 to 4.78.25.2544.78.25.25530
2094.78.26.0/274.78.26.1 to 4.78.26.304.78.26.3130
2104.78.26.32/274.78.26.33 to 4.78.26.624.78.26.6330
2114.78.26.64/274.78.26.65 to 4.78.26.944.78.26.9530
2124.78.26.96/274.78.26.97 to 4.78.26.1264.78.26.12730
2134.78.26.128/274.78.26.129 to 4.78.26.1584.78.26.15930
2144.78.26.160/274.78.26.161 to 4.78.26.1904.78.26.19130
2154.78.26.192/274.78.26.193 to 4.78.26.2224.78.26.22330
2164.78.26.224/274.78.26.225 to 4.78.26.2544.78.26.25530
2174.78.27.0/274.78.27.1 to 4.78.27.304.78.27.3130
2184.78.27.32/274.78.27.33 to 4.78.27.624.78.27.6330
2194.78.27.64/274.78.27.65 to 4.78.27.944.78.27.9530
2204.78.27.96/274.78.27.97 to 4.78.27.1264.78.27.12730
2214.78.27.128/274.78.27.129 to 4.78.27.1584.78.27.15930
2224.78.27.160/274.78.27.161 to 4.78.27.1904.78.27.19130
2234.78.27.192/274.78.27.193 to 4.78.27.2224.78.27.22330
2244.78.27.224/274.78.27.225 to 4.78.27.2544.78.27.25530
2254.78.28.0/274.78.28.1 to 4.78.28.304.78.28.3130
2264.78.28.32/274.78.28.33 to 4.78.28.624.78.28.6330
2274.78.28.64/274.78.28.65 to 4.78.28.944.78.28.9530
2284.78.28.96/274.78.28.97 to 4.78.28.1264.78.28.12730
2294.78.28.128/274.78.28.129 to 4.78.28.1584.78.28.15930
2304.78.28.160/274.78.28.161 to 4.78.28.1904.78.28.19130
2314.78.28.192/274.78.28.193 to 4.78.28.2224.78.28.22330
2324.78.28.224/274.78.28.225 to 4.78.28.2544.78.28.25530
2334.78.29.0/274.78.29.1 to 4.78.29.304.78.29.3130
2344.78.29.32/274.78.29.33 to 4.78.29.624.78.29.6330
2354.78.29.64/274.78.29.65 to 4.78.29.944.78.29.9530
2364.78.29.96/274.78.29.97 to 4.78.29.1264.78.29.12730
2374.78.29.128/274.78.29.129 to 4.78.29.1584.78.29.15930
2384.78.29.160/274.78.29.161 to 4.78.29.1904.78.29.19130
2394.78.29.192/274.78.29.193 to 4.78.29.2224.78.29.22330
2404.78.29.224/274.78.29.225 to 4.78.29.2544.78.29.25530
2414.78.30.0/274.78.30.1 to 4.78.30.304.78.30.3130
2424.78.30.32/274.78.30.33 to 4.78.30.624.78.30.6330
2434.78.30.64/274.78.30.65 to 4.78.30.944.78.30.9530
2444.78.30.96/274.78.30.97 to 4.78.30.1264.78.30.12730
2454.78.30.128/274.78.30.129 to 4.78.30.1584.78.30.15930
2464.78.30.160/274.78.30.161 to 4.78.30.1904.78.30.19130
2474.78.30.192/274.78.30.193 to 4.78.30.2224.78.30.22330
2484.78.30.224/274.78.30.225 to 4.78.30.2544.78.30.25530
2494.78.31.0/274.78.31.1 to 4.78.31.304.78.31.3130
2504.78.31.32/274.78.31.33 to 4.78.31.624.78.31.6330
2514.78.31.64/274.78.31.65 to 4.78.31.944.78.31.9530
2524.78.31.96/274.78.31.97 to 4.78.31.1264.78.31.12730
2534.78.31.128/274.78.31.129 to 4.78.31.1584.78.31.15930
2544.78.31.160/274.78.31.161 to 4.78.31.1904.78.31.19130
2554.78.31.192/274.78.31.193 to 4.78.31.2224.78.31.22330
2564.78.31.224/274.78.31.225 to 4.78.31.2544.78.31.25530

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