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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.

Prefix/16
Addresses2^112
/64 networks2^48
Network
2eee::/16
First address
2eee::
Last address
2eee:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
5,192,296,858,534,827,628,530,496,329,220,096 (2^112)
/64 networks (LANs)
281,474,976,710,656 (2^48)
Full form
2eee:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
e.e.e.2.ip6.arpa
Split into smaller subnets/24
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

2eee::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
12eee::/242eee:ff:ffff:ffff:ffff:ffff:ffff:ffff
22eee:100::/242eee:1ff:ffff:ffff:ffff:ffff:ffff:ffff
32eee:200::/242eee:2ff:ffff:ffff:ffff:ffff:ffff:ffff
42eee:300::/242eee:3ff:ffff:ffff:ffff:ffff:ffff:ffff
52eee:400::/242eee:4ff:ffff:ffff:ffff:ffff:ffff:ffff
62eee:500::/242eee:5ff:ffff:ffff:ffff:ffff:ffff:ffff
72eee:600::/242eee:6ff:ffff:ffff:ffff:ffff:ffff:ffff
82eee:700::/242eee:7ff:ffff:ffff:ffff:ffff:ffff:ffff
92eee:800::/242eee:8ff:ffff:ffff:ffff:ffff:ffff:ffff
102eee:900::/242eee:9ff:ffff:ffff:ffff:ffff:ffff:ffff
112eee:a00::/242eee:aff:ffff:ffff:ffff:ffff:ffff:ffff
122eee:b00::/242eee:bff:ffff:ffff:ffff:ffff:ffff:ffff
132eee:c00::/242eee:cff:ffff:ffff:ffff:ffff:ffff:ffff
142eee:d00::/242eee:dff:ffff:ffff:ffff:ffff:ffff:ffff
152eee:e00::/242eee:eff:ffff:ffff:ffff:ffff:ffff:ffff
162eee:f00::/242eee:fff:ffff:ffff:ffff:ffff:ffff:ffff
172eee:1000::/242eee:10ff:ffff:ffff:ffff:ffff:ffff:ffff
182eee:1100::/242eee:11ff:ffff:ffff:ffff:ffff:ffff:ffff
192eee:1200::/242eee:12ff:ffff:ffff:ffff:ffff:ffff:ffff
202eee:1300::/242eee:13ff:ffff:ffff:ffff:ffff:ffff:ffff
212eee:1400::/242eee:14ff:ffff:ffff:ffff:ffff:ffff:ffff
222eee:1500::/242eee:15ff:ffff:ffff:ffff:ffff:ffff:ffff
232eee:1600::/242eee:16ff:ffff:ffff:ffff:ffff:ffff:ffff
242eee:1700::/242eee:17ff:ffff:ffff:ffff:ffff:ffff:ffff
252eee:1800::/242eee:18ff:ffff:ffff:ffff:ffff:ffff:ffff
262eee:1900::/242eee:19ff:ffff:ffff:ffff:ffff:ffff:ffff
272eee:1a00::/242eee:1aff:ffff:ffff:ffff:ffff:ffff:ffff
282eee:1b00::/242eee:1bff:ffff:ffff:ffff:ffff:ffff:ffff
292eee:1c00::/242eee:1cff:ffff:ffff:ffff:ffff:ffff:ffff
302eee:1d00::/242eee:1dff:ffff:ffff:ffff:ffff:ffff:ffff
312eee:1e00::/242eee:1eff:ffff:ffff:ffff:ffff:ffff:ffff
322eee:1f00::/242eee:1fff:ffff:ffff:ffff:ffff:ffff:ffff
332eee:2000::/242eee:20ff:ffff:ffff:ffff:ffff:ffff:ffff
342eee:2100::/242eee:21ff:ffff:ffff:ffff:ffff:ffff:ffff
352eee:2200::/242eee:22ff:ffff:ffff:ffff:ffff:ffff:ffff
362eee:2300::/242eee:23ff:ffff:ffff:ffff:ffff:ffff:ffff
372eee:2400::/242eee:24ff:ffff:ffff:ffff:ffff:ffff:ffff
382eee:2500::/242eee:25ff:ffff:ffff:ffff:ffff:ffff:ffff
392eee:2600::/242eee:26ff:ffff:ffff:ffff:ffff:ffff:ffff
402eee:2700::/242eee:27ff:ffff:ffff:ffff:ffff:ffff:ffff
412eee:2800::/242eee:28ff:ffff:ffff:ffff:ffff:ffff:ffff
422eee:2900::/242eee:29ff:ffff:ffff:ffff:ffff:ffff:ffff
432eee:2a00::/242eee:2aff:ffff:ffff:ffff:ffff:ffff:ffff
442eee:2b00::/242eee:2bff:ffff:ffff:ffff:ffff:ffff:ffff
452eee:2c00::/242eee:2cff:ffff:ffff:ffff:ffff:ffff:ffff
462eee:2d00::/242eee:2dff:ffff:ffff:ffff:ffff:ffff:ffff
472eee:2e00::/242eee:2eff:ffff:ffff:ffff:ffff:ffff:ffff
482eee:2f00::/242eee:2fff:ffff:ffff:ffff:ffff:ffff:ffff
492eee:3000::/242eee:30ff:ffff:ffff:ffff:ffff:ffff:ffff
502eee:3100::/242eee:31ff:ffff:ffff:ffff:ffff:ffff:ffff
512eee:3200::/242eee:32ff:ffff:ffff:ffff:ffff:ffff:ffff
522eee:3300::/242eee:33ff:ffff:ffff:ffff:ffff:ffff:ffff
532eee:3400::/242eee:34ff:ffff:ffff:ffff:ffff:ffff:ffff
542eee:3500::/242eee:35ff:ffff:ffff:ffff:ffff:ffff:ffff
552eee:3600::/242eee:36ff:ffff:ffff:ffff:ffff:ffff:ffff
562eee:3700::/242eee:37ff:ffff:ffff:ffff:ffff:ffff:ffff
572eee:3800::/242eee:38ff:ffff:ffff:ffff:ffff:ffff:ffff
582eee:3900::/242eee:39ff:ffff:ffff:ffff:ffff:ffff:ffff
592eee:3a00::/242eee:3aff:ffff:ffff:ffff:ffff:ffff:ffff
602eee:3b00::/242eee:3bff:ffff:ffff:ffff:ffff:ffff:ffff
612eee:3c00::/242eee:3cff:ffff:ffff:ffff:ffff:ffff:ffff
622eee:3d00::/242eee:3dff:ffff:ffff:ffff:ffff:ffff:ffff
632eee:3e00::/242eee:3eff:ffff:ffff:ffff:ffff:ffff:ffff
642eee:3f00::/242eee:3fff:ffff:ffff:ffff:ffff:ffff:ffff
652eee:4000::/242eee:40ff:ffff:ffff:ffff:ffff:ffff:ffff
662eee:4100::/242eee:41ff:ffff:ffff:ffff:ffff:ffff:ffff
672eee:4200::/242eee:42ff:ffff:ffff:ffff:ffff:ffff:ffff
682eee:4300::/242eee:43ff:ffff:ffff:ffff:ffff:ffff:ffff
692eee:4400::/242eee:44ff:ffff:ffff:ffff:ffff:ffff:ffff
702eee:4500::/242eee:45ff:ffff:ffff:ffff:ffff:ffff:ffff
712eee:4600::/242eee:46ff:ffff:ffff:ffff:ffff:ffff:ffff
722eee:4700::/242eee:47ff:ffff:ffff:ffff:ffff:ffff:ffff
732eee:4800::/242eee:48ff:ffff:ffff:ffff:ffff:ffff:ffff
742eee:4900::/242eee:49ff:ffff:ffff:ffff:ffff:ffff:ffff
752eee:4a00::/242eee:4aff:ffff:ffff:ffff:ffff:ffff:ffff
762eee:4b00::/242eee:4bff:ffff:ffff:ffff:ffff:ffff:ffff
772eee:4c00::/242eee:4cff:ffff:ffff:ffff:ffff:ffff:ffff
782eee:4d00::/242eee:4dff:ffff:ffff:ffff:ffff:ffff:ffff
792eee:4e00::/242eee:4eff:ffff:ffff:ffff:ffff:ffff:ffff
802eee:4f00::/242eee:4fff:ffff:ffff:ffff:ffff:ffff:ffff
812eee:5000::/242eee:50ff:ffff:ffff:ffff:ffff:ffff:ffff
822eee:5100::/242eee:51ff:ffff:ffff:ffff:ffff:ffff:ffff
832eee:5200::/242eee:52ff:ffff:ffff:ffff:ffff:ffff:ffff
842eee:5300::/242eee:53ff:ffff:ffff:ffff:ffff:ffff:ffff
852eee:5400::/242eee:54ff:ffff:ffff:ffff:ffff:ffff:ffff
862eee:5500::/242eee:55ff:ffff:ffff:ffff:ffff:ffff:ffff
872eee:5600::/242eee:56ff:ffff:ffff:ffff:ffff:ffff:ffff
882eee:5700::/242eee:57ff:ffff:ffff:ffff:ffff:ffff:ffff
892eee:5800::/242eee:58ff:ffff:ffff:ffff:ffff:ffff:ffff
902eee:5900::/242eee:59ff:ffff:ffff:ffff:ffff:ffff:ffff
912eee:5a00::/242eee:5aff:ffff:ffff:ffff:ffff:ffff:ffff
922eee:5b00::/242eee:5bff:ffff:ffff:ffff:ffff:ffff:ffff
932eee:5c00::/242eee:5cff:ffff:ffff:ffff:ffff:ffff:ffff
942eee:5d00::/242eee:5dff:ffff:ffff:ffff:ffff:ffff:ffff
952eee:5e00::/242eee:5eff:ffff:ffff:ffff:ffff:ffff:ffff
962eee:5f00::/242eee:5fff:ffff:ffff:ffff:ffff:ffff:ffff
972eee:6000::/242eee:60ff:ffff:ffff:ffff:ffff:ffff:ffff
982eee:6100::/242eee:61ff:ffff:ffff:ffff:ffff:ffff:ffff
992eee:6200::/242eee:62ff:ffff:ffff:ffff:ffff:ffff:ffff
1002eee:6300::/242eee:63ff:ffff:ffff:ffff:ffff:ffff:ffff
1012eee:6400::/242eee:64ff:ffff:ffff:ffff:ffff:ffff:ffff
1022eee:6500::/242eee:65ff:ffff:ffff:ffff:ffff:ffff:ffff
1032eee:6600::/242eee:66ff:ffff:ffff:ffff:ffff:ffff:ffff
1042eee:6700::/242eee:67ff:ffff:ffff:ffff:ffff:ffff:ffff
1052eee:6800::/242eee:68ff:ffff:ffff:ffff:ffff:ffff:ffff
1062eee:6900::/242eee:69ff:ffff:ffff:ffff:ffff:ffff:ffff
1072eee:6a00::/242eee:6aff:ffff:ffff:ffff:ffff:ffff:ffff
1082eee:6b00::/242eee:6bff:ffff:ffff:ffff:ffff:ffff:ffff
1092eee:6c00::/242eee:6cff:ffff:ffff:ffff:ffff:ffff:ffff
1102eee:6d00::/242eee:6dff:ffff:ffff:ffff:ffff:ffff:ffff
1112eee:6e00::/242eee:6eff:ffff:ffff:ffff:ffff:ffff:ffff
1122eee:6f00::/242eee:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1132eee:7000::/242eee:70ff:ffff:ffff:ffff:ffff:ffff:ffff
1142eee:7100::/242eee:71ff:ffff:ffff:ffff:ffff:ffff:ffff
1152eee:7200::/242eee:72ff:ffff:ffff:ffff:ffff:ffff:ffff
1162eee:7300::/242eee:73ff:ffff:ffff:ffff:ffff:ffff:ffff
1172eee:7400::/242eee:74ff:ffff:ffff:ffff:ffff:ffff:ffff
1182eee:7500::/242eee:75ff:ffff:ffff:ffff:ffff:ffff:ffff
1192eee:7600::/242eee:76ff:ffff:ffff:ffff:ffff:ffff:ffff
1202eee:7700::/242eee:77ff:ffff:ffff:ffff:ffff:ffff:ffff
1212eee:7800::/242eee:78ff:ffff:ffff:ffff:ffff:ffff:ffff
1222eee:7900::/242eee:79ff:ffff:ffff:ffff:ffff:ffff:ffff
1232eee:7a00::/242eee:7aff:ffff:ffff:ffff:ffff:ffff:ffff
1242eee:7b00::/242eee:7bff:ffff:ffff:ffff:ffff:ffff:ffff
1252eee:7c00::/242eee:7cff:ffff:ffff:ffff:ffff:ffff:ffff
1262eee:7d00::/242eee:7dff:ffff:ffff:ffff:ffff:ffff:ffff
1272eee:7e00::/242eee:7eff:ffff:ffff:ffff:ffff:ffff:ffff
1282eee:7f00::/242eee:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1292eee:8000::/242eee:80ff:ffff:ffff:ffff:ffff:ffff:ffff
1302eee:8100::/242eee:81ff:ffff:ffff:ffff:ffff:ffff:ffff
1312eee:8200::/242eee:82ff:ffff:ffff:ffff:ffff:ffff:ffff
1322eee:8300::/242eee:83ff:ffff:ffff:ffff:ffff:ffff:ffff
1332eee:8400::/242eee:84ff:ffff:ffff:ffff:ffff:ffff:ffff
1342eee:8500::/242eee:85ff:ffff:ffff:ffff:ffff:ffff:ffff
1352eee:8600::/242eee:86ff:ffff:ffff:ffff:ffff:ffff:ffff
1362eee:8700::/242eee:87ff:ffff:ffff:ffff:ffff:ffff:ffff
1372eee:8800::/242eee:88ff:ffff:ffff:ffff:ffff:ffff:ffff
1382eee:8900::/242eee:89ff:ffff:ffff:ffff:ffff:ffff:ffff
1392eee:8a00::/242eee:8aff:ffff:ffff:ffff:ffff:ffff:ffff
1402eee:8b00::/242eee:8bff:ffff:ffff:ffff:ffff:ffff:ffff
1412eee:8c00::/242eee:8cff:ffff:ffff:ffff:ffff:ffff:ffff
1422eee:8d00::/242eee:8dff:ffff:ffff:ffff:ffff:ffff:ffff
1432eee:8e00::/242eee:8eff:ffff:ffff:ffff:ffff:ffff:ffff
1442eee:8f00::/242eee:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1452eee:9000::/242eee:90ff:ffff:ffff:ffff:ffff:ffff:ffff
1462eee:9100::/242eee:91ff:ffff:ffff:ffff:ffff:ffff:ffff
1472eee:9200::/242eee:92ff:ffff:ffff:ffff:ffff:ffff:ffff
1482eee:9300::/242eee:93ff:ffff:ffff:ffff:ffff:ffff:ffff
1492eee:9400::/242eee:94ff:ffff:ffff:ffff:ffff:ffff:ffff
1502eee:9500::/242eee:95ff:ffff:ffff:ffff:ffff:ffff:ffff
1512eee:9600::/242eee:96ff:ffff:ffff:ffff:ffff:ffff:ffff
1522eee:9700::/242eee:97ff:ffff:ffff:ffff:ffff:ffff:ffff
1532eee:9800::/242eee:98ff:ffff:ffff:ffff:ffff:ffff:ffff
1542eee:9900::/242eee:99ff:ffff:ffff:ffff:ffff:ffff:ffff
1552eee:9a00::/242eee:9aff:ffff:ffff:ffff:ffff:ffff:ffff
1562eee:9b00::/242eee:9bff:ffff:ffff:ffff:ffff:ffff:ffff
1572eee:9c00::/242eee:9cff:ffff:ffff:ffff:ffff:ffff:ffff
1582eee:9d00::/242eee:9dff:ffff:ffff:ffff:ffff:ffff:ffff
1592eee:9e00::/242eee:9eff:ffff:ffff:ffff:ffff:ffff:ffff
1602eee:9f00::/242eee:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1612eee:a000::/242eee:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
1622eee:a100::/242eee:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
1632eee:a200::/242eee:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
1642eee:a300::/242eee:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
1652eee:a400::/242eee:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
1662eee:a500::/242eee:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
1672eee:a600::/242eee:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
1682eee:a700::/242eee:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
1692eee:a800::/242eee:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
1702eee:a900::/242eee:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
1712eee:aa00::/242eee:aaff:ffff:ffff:ffff:ffff:ffff:ffff
1722eee:ab00::/242eee:abff:ffff:ffff:ffff:ffff:ffff:ffff
1732eee:ac00::/242eee:acff:ffff:ffff:ffff:ffff:ffff:ffff
1742eee:ad00::/242eee:adff:ffff:ffff:ffff:ffff:ffff:ffff
1752eee:ae00::/242eee:aeff:ffff:ffff:ffff:ffff:ffff:ffff
1762eee:af00::/242eee:afff:ffff:ffff:ffff:ffff:ffff:ffff
1772eee:b000::/242eee:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
1782eee:b100::/242eee:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
1792eee:b200::/242eee:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
1802eee:b300::/242eee:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
1812eee:b400::/242eee:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
1822eee:b500::/242eee:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
1832eee:b600::/242eee:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
1842eee:b700::/242eee:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
1852eee:b800::/242eee:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
1862eee:b900::/242eee:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
1872eee:ba00::/242eee:baff:ffff:ffff:ffff:ffff:ffff:ffff
1882eee:bb00::/242eee:bbff:ffff:ffff:ffff:ffff:ffff:ffff
1892eee:bc00::/242eee:bcff:ffff:ffff:ffff:ffff:ffff:ffff
1902eee:bd00::/242eee:bdff:ffff:ffff:ffff:ffff:ffff:ffff
1912eee:be00::/242eee:beff:ffff:ffff:ffff:ffff:ffff:ffff
1922eee:bf00::/242eee:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1932eee:c000::/242eee:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
1942eee:c100::/242eee:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
1952eee:c200::/242eee:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
1962eee:c300::/242eee:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
1972eee:c400::/242eee:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
1982eee:c500::/242eee:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
1992eee:c600::/242eee:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
2002eee:c700::/242eee:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
2012eee:c800::/242eee:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
2022eee:c900::/242eee:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
2032eee:ca00::/242eee:caff:ffff:ffff:ffff:ffff:ffff:ffff
2042eee:cb00::/242eee:cbff:ffff:ffff:ffff:ffff:ffff:ffff
2052eee:cc00::/242eee:ccff:ffff:ffff:ffff:ffff:ffff:ffff
2062eee:cd00::/242eee:cdff:ffff:ffff:ffff:ffff:ffff:ffff
2072eee:ce00::/242eee:ceff:ffff:ffff:ffff:ffff:ffff:ffff
2082eee:cf00::/242eee:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2092eee:d000::/242eee:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
2102eee:d100::/242eee:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
2112eee:d200::/242eee:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
2122eee:d300::/242eee:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
2132eee:d400::/242eee:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
2142eee:d500::/242eee:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
2152eee:d600::/242eee:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
2162eee:d700::/242eee:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
2172eee:d800::/242eee:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
2182eee:d900::/242eee:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
2192eee:da00::/242eee:daff:ffff:ffff:ffff:ffff:ffff:ffff
2202eee:db00::/242eee:dbff:ffff:ffff:ffff:ffff:ffff:ffff
2212eee:dc00::/242eee:dcff:ffff:ffff:ffff:ffff:ffff:ffff
2222eee:dd00::/242eee:ddff:ffff:ffff:ffff:ffff:ffff:ffff
2232eee:de00::/242eee:deff:ffff:ffff:ffff:ffff:ffff:ffff
2242eee:df00::/242eee:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2252eee:e000::/242eee:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
2262eee:e100::/242eee:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
2272eee:e200::/242eee:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
2282eee:e300::/242eee:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
2292eee:e400::/242eee:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
2302eee:e500::/242eee:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
2312eee:e600::/242eee:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
2322eee:e700::/242eee:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
2332eee:e800::/242eee:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
2342eee:e900::/242eee:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
2352eee:ea00::/242eee:eaff:ffff:ffff:ffff:ffff:ffff:ffff
2362eee:eb00::/242eee:ebff:ffff:ffff:ffff:ffff:ffff:ffff
2372eee:ec00::/242eee:ecff:ffff:ffff:ffff:ffff:ffff:ffff
2382eee:ed00::/242eee:edff:ffff:ffff:ffff:ffff:ffff:ffff
2392eee:ee00::/242eee:eeff:ffff:ffff:ffff:ffff:ffff:ffff
2402eee:ef00::/242eee:efff:ffff:ffff:ffff:ffff:ffff:ffff
2412eee:f000::/242eee:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
2422eee:f100::/242eee:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
2432eee:f200::/242eee:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
2442eee:f300::/242eee:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
2452eee:f400::/242eee:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
2462eee:f500::/242eee:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
2472eee:f600::/242eee:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
2482eee:f700::/242eee:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
2492eee:f800::/242eee:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
2502eee:f900::/242eee:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
2512eee:fa00::/242eee:faff:ffff:ffff:ffff:ffff:ffff:ffff
2522eee:fb00::/242eee:fbff:ffff:ffff:ffff:ffff:ffff:ffff
2532eee:fc00::/242eee:fcff:ffff:ffff:ffff:ffff:ffff:ffff
2542eee:fd00::/242eee:fdff:ffff:ffff:ffff:ffff:ffff:ffff
2552eee:fe00::/242eee:feff:ffff:ffff:ffff:ffff:ffff:ffff
2562eee:ff00::/242eee:ffff:ffff:ffff:ffff:ffff:ffff:ffff

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

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.