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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
2eec::/16
First address
2eec::
Last address
2eec: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
2eec:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
c.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)

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

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