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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/12
Addresses2^116
/64 networks2^52
Network
2b60::/12
First address
2b60::
Last address
2b6f:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
83,076,749,736,557,242,056,487,941,267,521,536 (2^116)
/64 networks (LANs)
4,503,599,627,370,496 (2^52)
Full form
2b60:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
6.b.2.ip6.arpa
Split into smaller subnets/24
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

2b60::/12 makes 4,096 subnets of /24; the first 256 are listed.

Subnets
#SubnetLast address
12b60::/242b60:ff:ffff:ffff:ffff:ffff:ffff:ffff
22b60:100::/242b60:1ff:ffff:ffff:ffff:ffff:ffff:ffff
32b60:200::/242b60:2ff:ffff:ffff:ffff:ffff:ffff:ffff
42b60:300::/242b60:3ff:ffff:ffff:ffff:ffff:ffff:ffff
52b60:400::/242b60:4ff:ffff:ffff:ffff:ffff:ffff:ffff
62b60:500::/242b60:5ff:ffff:ffff:ffff:ffff:ffff:ffff
72b60:600::/242b60:6ff:ffff:ffff:ffff:ffff:ffff:ffff
82b60:700::/242b60:7ff:ffff:ffff:ffff:ffff:ffff:ffff
92b60:800::/242b60:8ff:ffff:ffff:ffff:ffff:ffff:ffff
102b60:900::/242b60:9ff:ffff:ffff:ffff:ffff:ffff:ffff
112b60:a00::/242b60:aff:ffff:ffff:ffff:ffff:ffff:ffff
122b60:b00::/242b60:bff:ffff:ffff:ffff:ffff:ffff:ffff
132b60:c00::/242b60:cff:ffff:ffff:ffff:ffff:ffff:ffff
142b60:d00::/242b60:dff:ffff:ffff:ffff:ffff:ffff:ffff
152b60:e00::/242b60:eff:ffff:ffff:ffff:ffff:ffff:ffff
162b60:f00::/242b60:fff:ffff:ffff:ffff:ffff:ffff:ffff
172b60:1000::/242b60:10ff:ffff:ffff:ffff:ffff:ffff:ffff
182b60:1100::/242b60:11ff:ffff:ffff:ffff:ffff:ffff:ffff
192b60:1200::/242b60:12ff:ffff:ffff:ffff:ffff:ffff:ffff
202b60:1300::/242b60:13ff:ffff:ffff:ffff:ffff:ffff:ffff
212b60:1400::/242b60:14ff:ffff:ffff:ffff:ffff:ffff:ffff
222b60:1500::/242b60:15ff:ffff:ffff:ffff:ffff:ffff:ffff
232b60:1600::/242b60:16ff:ffff:ffff:ffff:ffff:ffff:ffff
242b60:1700::/242b60:17ff:ffff:ffff:ffff:ffff:ffff:ffff
252b60:1800::/242b60:18ff:ffff:ffff:ffff:ffff:ffff:ffff
262b60:1900::/242b60:19ff:ffff:ffff:ffff:ffff:ffff:ffff
272b60:1a00::/242b60:1aff:ffff:ffff:ffff:ffff:ffff:ffff
282b60:1b00::/242b60:1bff:ffff:ffff:ffff:ffff:ffff:ffff
292b60:1c00::/242b60:1cff:ffff:ffff:ffff:ffff:ffff:ffff
302b60:1d00::/242b60:1dff:ffff:ffff:ffff:ffff:ffff:ffff
312b60:1e00::/242b60:1eff:ffff:ffff:ffff:ffff:ffff:ffff
322b60:1f00::/242b60:1fff:ffff:ffff:ffff:ffff:ffff:ffff
332b60:2000::/242b60:20ff:ffff:ffff:ffff:ffff:ffff:ffff
342b60:2100::/242b60:21ff:ffff:ffff:ffff:ffff:ffff:ffff
352b60:2200::/242b60:22ff:ffff:ffff:ffff:ffff:ffff:ffff
362b60:2300::/242b60:23ff:ffff:ffff:ffff:ffff:ffff:ffff
372b60:2400::/242b60:24ff:ffff:ffff:ffff:ffff:ffff:ffff
382b60:2500::/242b60:25ff:ffff:ffff:ffff:ffff:ffff:ffff
392b60:2600::/242b60:26ff:ffff:ffff:ffff:ffff:ffff:ffff
402b60:2700::/242b60:27ff:ffff:ffff:ffff:ffff:ffff:ffff
412b60:2800::/242b60:28ff:ffff:ffff:ffff:ffff:ffff:ffff
422b60:2900::/242b60:29ff:ffff:ffff:ffff:ffff:ffff:ffff
432b60:2a00::/242b60:2aff:ffff:ffff:ffff:ffff:ffff:ffff
442b60:2b00::/242b60:2bff:ffff:ffff:ffff:ffff:ffff:ffff
452b60:2c00::/242b60:2cff:ffff:ffff:ffff:ffff:ffff:ffff
462b60:2d00::/242b60:2dff:ffff:ffff:ffff:ffff:ffff:ffff
472b60:2e00::/242b60:2eff:ffff:ffff:ffff:ffff:ffff:ffff
482b60:2f00::/242b60:2fff:ffff:ffff:ffff:ffff:ffff:ffff
492b60:3000::/242b60:30ff:ffff:ffff:ffff:ffff:ffff:ffff
502b60:3100::/242b60:31ff:ffff:ffff:ffff:ffff:ffff:ffff
512b60:3200::/242b60:32ff:ffff:ffff:ffff:ffff:ffff:ffff
522b60:3300::/242b60:33ff:ffff:ffff:ffff:ffff:ffff:ffff
532b60:3400::/242b60:34ff:ffff:ffff:ffff:ffff:ffff:ffff
542b60:3500::/242b60:35ff:ffff:ffff:ffff:ffff:ffff:ffff
552b60:3600::/242b60:36ff:ffff:ffff:ffff:ffff:ffff:ffff
562b60:3700::/242b60:37ff:ffff:ffff:ffff:ffff:ffff:ffff
572b60:3800::/242b60:38ff:ffff:ffff:ffff:ffff:ffff:ffff
582b60:3900::/242b60:39ff:ffff:ffff:ffff:ffff:ffff:ffff
592b60:3a00::/242b60:3aff:ffff:ffff:ffff:ffff:ffff:ffff
602b60:3b00::/242b60:3bff:ffff:ffff:ffff:ffff:ffff:ffff
612b60:3c00::/242b60:3cff:ffff:ffff:ffff:ffff:ffff:ffff
622b60:3d00::/242b60:3dff:ffff:ffff:ffff:ffff:ffff:ffff
632b60:3e00::/242b60:3eff:ffff:ffff:ffff:ffff:ffff:ffff
642b60:3f00::/242b60:3fff:ffff:ffff:ffff:ffff:ffff:ffff
652b60:4000::/242b60:40ff:ffff:ffff:ffff:ffff:ffff:ffff
662b60:4100::/242b60:41ff:ffff:ffff:ffff:ffff:ffff:ffff
672b60:4200::/242b60:42ff:ffff:ffff:ffff:ffff:ffff:ffff
682b60:4300::/242b60:43ff:ffff:ffff:ffff:ffff:ffff:ffff
692b60:4400::/242b60:44ff:ffff:ffff:ffff:ffff:ffff:ffff
702b60:4500::/242b60:45ff:ffff:ffff:ffff:ffff:ffff:ffff
712b60:4600::/242b60:46ff:ffff:ffff:ffff:ffff:ffff:ffff
722b60:4700::/242b60:47ff:ffff:ffff:ffff:ffff:ffff:ffff
732b60:4800::/242b60:48ff:ffff:ffff:ffff:ffff:ffff:ffff
742b60:4900::/242b60:49ff:ffff:ffff:ffff:ffff:ffff:ffff
752b60:4a00::/242b60:4aff:ffff:ffff:ffff:ffff:ffff:ffff
762b60:4b00::/242b60:4bff:ffff:ffff:ffff:ffff:ffff:ffff
772b60:4c00::/242b60:4cff:ffff:ffff:ffff:ffff:ffff:ffff
782b60:4d00::/242b60:4dff:ffff:ffff:ffff:ffff:ffff:ffff
792b60:4e00::/242b60:4eff:ffff:ffff:ffff:ffff:ffff:ffff
802b60:4f00::/242b60:4fff:ffff:ffff:ffff:ffff:ffff:ffff
812b60:5000::/242b60:50ff:ffff:ffff:ffff:ffff:ffff:ffff
822b60:5100::/242b60:51ff:ffff:ffff:ffff:ffff:ffff:ffff
832b60:5200::/242b60:52ff:ffff:ffff:ffff:ffff:ffff:ffff
842b60:5300::/242b60:53ff:ffff:ffff:ffff:ffff:ffff:ffff
852b60:5400::/242b60:54ff:ffff:ffff:ffff:ffff:ffff:ffff
862b60:5500::/242b60:55ff:ffff:ffff:ffff:ffff:ffff:ffff
872b60:5600::/242b60:56ff:ffff:ffff:ffff:ffff:ffff:ffff
882b60:5700::/242b60:57ff:ffff:ffff:ffff:ffff:ffff:ffff
892b60:5800::/242b60:58ff:ffff:ffff:ffff:ffff:ffff:ffff
902b60:5900::/242b60:59ff:ffff:ffff:ffff:ffff:ffff:ffff
912b60:5a00::/242b60:5aff:ffff:ffff:ffff:ffff:ffff:ffff
922b60:5b00::/242b60:5bff:ffff:ffff:ffff:ffff:ffff:ffff
932b60:5c00::/242b60:5cff:ffff:ffff:ffff:ffff:ffff:ffff
942b60:5d00::/242b60:5dff:ffff:ffff:ffff:ffff:ffff:ffff
952b60:5e00::/242b60:5eff:ffff:ffff:ffff:ffff:ffff:ffff
962b60:5f00::/242b60:5fff:ffff:ffff:ffff:ffff:ffff:ffff
972b60:6000::/242b60:60ff:ffff:ffff:ffff:ffff:ffff:ffff
982b60:6100::/242b60:61ff:ffff:ffff:ffff:ffff:ffff:ffff
992b60:6200::/242b60:62ff:ffff:ffff:ffff:ffff:ffff:ffff
1002b60:6300::/242b60:63ff:ffff:ffff:ffff:ffff:ffff:ffff
1012b60:6400::/242b60:64ff:ffff:ffff:ffff:ffff:ffff:ffff
1022b60:6500::/242b60:65ff:ffff:ffff:ffff:ffff:ffff:ffff
1032b60:6600::/242b60:66ff:ffff:ffff:ffff:ffff:ffff:ffff
1042b60:6700::/242b60:67ff:ffff:ffff:ffff:ffff:ffff:ffff
1052b60:6800::/242b60:68ff:ffff:ffff:ffff:ffff:ffff:ffff
1062b60:6900::/242b60:69ff:ffff:ffff:ffff:ffff:ffff:ffff
1072b60:6a00::/242b60:6aff:ffff:ffff:ffff:ffff:ffff:ffff
1082b60:6b00::/242b60:6bff:ffff:ffff:ffff:ffff:ffff:ffff
1092b60:6c00::/242b60:6cff:ffff:ffff:ffff:ffff:ffff:ffff
1102b60:6d00::/242b60:6dff:ffff:ffff:ffff:ffff:ffff:ffff
1112b60:6e00::/242b60:6eff:ffff:ffff:ffff:ffff:ffff:ffff
1122b60:6f00::/242b60:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1132b60:7000::/242b60:70ff:ffff:ffff:ffff:ffff:ffff:ffff
1142b60:7100::/242b60:71ff:ffff:ffff:ffff:ffff:ffff:ffff
1152b60:7200::/242b60:72ff:ffff:ffff:ffff:ffff:ffff:ffff
1162b60:7300::/242b60:73ff:ffff:ffff:ffff:ffff:ffff:ffff
1172b60:7400::/242b60:74ff:ffff:ffff:ffff:ffff:ffff:ffff
1182b60:7500::/242b60:75ff:ffff:ffff:ffff:ffff:ffff:ffff
1192b60:7600::/242b60:76ff:ffff:ffff:ffff:ffff:ffff:ffff
1202b60:7700::/242b60:77ff:ffff:ffff:ffff:ffff:ffff:ffff
1212b60:7800::/242b60:78ff:ffff:ffff:ffff:ffff:ffff:ffff
1222b60:7900::/242b60:79ff:ffff:ffff:ffff:ffff:ffff:ffff
1232b60:7a00::/242b60:7aff:ffff:ffff:ffff:ffff:ffff:ffff
1242b60:7b00::/242b60:7bff:ffff:ffff:ffff:ffff:ffff:ffff
1252b60:7c00::/242b60:7cff:ffff:ffff:ffff:ffff:ffff:ffff
1262b60:7d00::/242b60:7dff:ffff:ffff:ffff:ffff:ffff:ffff
1272b60:7e00::/242b60:7eff:ffff:ffff:ffff:ffff:ffff:ffff
1282b60:7f00::/242b60:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1292b60:8000::/242b60:80ff:ffff:ffff:ffff:ffff:ffff:ffff
1302b60:8100::/242b60:81ff:ffff:ffff:ffff:ffff:ffff:ffff
1312b60:8200::/242b60:82ff:ffff:ffff:ffff:ffff:ffff:ffff
1322b60:8300::/242b60:83ff:ffff:ffff:ffff:ffff:ffff:ffff
1332b60:8400::/242b60:84ff:ffff:ffff:ffff:ffff:ffff:ffff
1342b60:8500::/242b60:85ff:ffff:ffff:ffff:ffff:ffff:ffff
1352b60:8600::/242b60:86ff:ffff:ffff:ffff:ffff:ffff:ffff
1362b60:8700::/242b60:87ff:ffff:ffff:ffff:ffff:ffff:ffff
1372b60:8800::/242b60:88ff:ffff:ffff:ffff:ffff:ffff:ffff
1382b60:8900::/242b60:89ff:ffff:ffff:ffff:ffff:ffff:ffff
1392b60:8a00::/242b60:8aff:ffff:ffff:ffff:ffff:ffff:ffff
1402b60:8b00::/242b60:8bff:ffff:ffff:ffff:ffff:ffff:ffff
1412b60:8c00::/242b60:8cff:ffff:ffff:ffff:ffff:ffff:ffff
1422b60:8d00::/242b60:8dff:ffff:ffff:ffff:ffff:ffff:ffff
1432b60:8e00::/242b60:8eff:ffff:ffff:ffff:ffff:ffff:ffff
1442b60:8f00::/242b60:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1452b60:9000::/242b60:90ff:ffff:ffff:ffff:ffff:ffff:ffff
1462b60:9100::/242b60:91ff:ffff:ffff:ffff:ffff:ffff:ffff
1472b60:9200::/242b60:92ff:ffff:ffff:ffff:ffff:ffff:ffff
1482b60:9300::/242b60:93ff:ffff:ffff:ffff:ffff:ffff:ffff
1492b60:9400::/242b60:94ff:ffff:ffff:ffff:ffff:ffff:ffff
1502b60:9500::/242b60:95ff:ffff:ffff:ffff:ffff:ffff:ffff
1512b60:9600::/242b60:96ff:ffff:ffff:ffff:ffff:ffff:ffff
1522b60:9700::/242b60:97ff:ffff:ffff:ffff:ffff:ffff:ffff
1532b60:9800::/242b60:98ff:ffff:ffff:ffff:ffff:ffff:ffff
1542b60:9900::/242b60:99ff:ffff:ffff:ffff:ffff:ffff:ffff
1552b60:9a00::/242b60:9aff:ffff:ffff:ffff:ffff:ffff:ffff
1562b60:9b00::/242b60:9bff:ffff:ffff:ffff:ffff:ffff:ffff
1572b60:9c00::/242b60:9cff:ffff:ffff:ffff:ffff:ffff:ffff
1582b60:9d00::/242b60:9dff:ffff:ffff:ffff:ffff:ffff:ffff
1592b60:9e00::/242b60:9eff:ffff:ffff:ffff:ffff:ffff:ffff
1602b60:9f00::/242b60:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1612b60:a000::/242b60:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
1622b60:a100::/242b60:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
1632b60:a200::/242b60:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
1642b60:a300::/242b60:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
1652b60:a400::/242b60:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
1662b60:a500::/242b60:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
1672b60:a600::/242b60:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
1682b60:a700::/242b60:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
1692b60:a800::/242b60:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
1702b60:a900::/242b60:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
1712b60:aa00::/242b60:aaff:ffff:ffff:ffff:ffff:ffff:ffff
1722b60:ab00::/242b60:abff:ffff:ffff:ffff:ffff:ffff:ffff
1732b60:ac00::/242b60:acff:ffff:ffff:ffff:ffff:ffff:ffff
1742b60:ad00::/242b60:adff:ffff:ffff:ffff:ffff:ffff:ffff
1752b60:ae00::/242b60:aeff:ffff:ffff:ffff:ffff:ffff:ffff
1762b60:af00::/242b60:afff:ffff:ffff:ffff:ffff:ffff:ffff
1772b60:b000::/242b60:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
1782b60:b100::/242b60:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
1792b60:b200::/242b60:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
1802b60:b300::/242b60:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
1812b60:b400::/242b60:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
1822b60:b500::/242b60:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
1832b60:b600::/242b60:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
1842b60:b700::/242b60:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
1852b60:b800::/242b60:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
1862b60:b900::/242b60:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
1872b60:ba00::/242b60:baff:ffff:ffff:ffff:ffff:ffff:ffff
1882b60:bb00::/242b60:bbff:ffff:ffff:ffff:ffff:ffff:ffff
1892b60:bc00::/242b60:bcff:ffff:ffff:ffff:ffff:ffff:ffff
1902b60:bd00::/242b60:bdff:ffff:ffff:ffff:ffff:ffff:ffff
1912b60:be00::/242b60:beff:ffff:ffff:ffff:ffff:ffff:ffff
1922b60:bf00::/242b60:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1932b60:c000::/242b60:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
1942b60:c100::/242b60:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
1952b60:c200::/242b60:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
1962b60:c300::/242b60:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
1972b60:c400::/242b60:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
1982b60:c500::/242b60:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
1992b60:c600::/242b60:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
2002b60:c700::/242b60:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
2012b60:c800::/242b60:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
2022b60:c900::/242b60:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
2032b60:ca00::/242b60:caff:ffff:ffff:ffff:ffff:ffff:ffff
2042b60:cb00::/242b60:cbff:ffff:ffff:ffff:ffff:ffff:ffff
2052b60:cc00::/242b60:ccff:ffff:ffff:ffff:ffff:ffff:ffff
2062b60:cd00::/242b60:cdff:ffff:ffff:ffff:ffff:ffff:ffff
2072b60:ce00::/242b60:ceff:ffff:ffff:ffff:ffff:ffff:ffff
2082b60:cf00::/242b60:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2092b60:d000::/242b60:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
2102b60:d100::/242b60:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
2112b60:d200::/242b60:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
2122b60:d300::/242b60:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
2132b60:d400::/242b60:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
2142b60:d500::/242b60:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
2152b60:d600::/242b60:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
2162b60:d700::/242b60:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
2172b60:d800::/242b60:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
2182b60:d900::/242b60:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
2192b60:da00::/242b60:daff:ffff:ffff:ffff:ffff:ffff:ffff
2202b60:db00::/242b60:dbff:ffff:ffff:ffff:ffff:ffff:ffff
2212b60:dc00::/242b60:dcff:ffff:ffff:ffff:ffff:ffff:ffff
2222b60:dd00::/242b60:ddff:ffff:ffff:ffff:ffff:ffff:ffff
2232b60:de00::/242b60:deff:ffff:ffff:ffff:ffff:ffff:ffff
2242b60:df00::/242b60:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2252b60:e000::/242b60:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
2262b60:e100::/242b60:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
2272b60:e200::/242b60:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
2282b60:e300::/242b60:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
2292b60:e400::/242b60:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
2302b60:e500::/242b60:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
2312b60:e600::/242b60:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
2322b60:e700::/242b60:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
2332b60:e800::/242b60:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
2342b60:e900::/242b60:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
2352b60:ea00::/242b60:eaff:ffff:ffff:ffff:ffff:ffff:ffff
2362b60:eb00::/242b60:ebff:ffff:ffff:ffff:ffff:ffff:ffff
2372b60:ec00::/242b60:ecff:ffff:ffff:ffff:ffff:ffff:ffff
2382b60:ed00::/242b60:edff:ffff:ffff:ffff:ffff:ffff:ffff
2392b60:ee00::/242b60:eeff:ffff:ffff:ffff:ffff:ffff:ffff
2402b60:ef00::/242b60:efff:ffff:ffff:ffff:ffff:ffff:ffff
2412b60:f000::/242b60:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
2422b60:f100::/242b60:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
2432b60:f200::/242b60:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
2442b60:f300::/242b60:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
2452b60:f400::/242b60:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
2462b60:f500::/242b60:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
2472b60:f600::/242b60:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
2482b60:f700::/242b60:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
2492b60:f800::/242b60:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
2502b60:f900::/242b60:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
2512b60:fa00::/242b60:faff:ffff:ffff:ffff:ffff:ffff:ffff
2522b60:fb00::/242b60:fbff:ffff:ffff:ffff:ffff:ffff:ffff
2532b60:fc00::/242b60:fcff:ffff:ffff:ffff:ffff:ffff:ffff
2542b60:fd00::/242b60:fdff:ffff:ffff:ffff:ffff:ffff:ffff
2552b60:fe00::/242b60:feff:ffff:ffff:ffff:ffff:ffff:ffff
2562b60:ff00::/242b60: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.