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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
2086::/16
First address
2086::
Last address
2086: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
2086:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
6.8.0.2.ip6.arpa
Split into smaller subnets/24
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

2086::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
12086::/242086:ff:ffff:ffff:ffff:ffff:ffff:ffff
22086:100::/242086:1ff:ffff:ffff:ffff:ffff:ffff:ffff
32086:200::/242086:2ff:ffff:ffff:ffff:ffff:ffff:ffff
42086:300::/242086:3ff:ffff:ffff:ffff:ffff:ffff:ffff
52086:400::/242086:4ff:ffff:ffff:ffff:ffff:ffff:ffff
62086:500::/242086:5ff:ffff:ffff:ffff:ffff:ffff:ffff
72086:600::/242086:6ff:ffff:ffff:ffff:ffff:ffff:ffff
82086:700::/242086:7ff:ffff:ffff:ffff:ffff:ffff:ffff
92086:800::/242086:8ff:ffff:ffff:ffff:ffff:ffff:ffff
102086:900::/242086:9ff:ffff:ffff:ffff:ffff:ffff:ffff
112086:a00::/242086:aff:ffff:ffff:ffff:ffff:ffff:ffff
122086:b00::/242086:bff:ffff:ffff:ffff:ffff:ffff:ffff
132086:c00::/242086:cff:ffff:ffff:ffff:ffff:ffff:ffff
142086:d00::/242086:dff:ffff:ffff:ffff:ffff:ffff:ffff
152086:e00::/242086:eff:ffff:ffff:ffff:ffff:ffff:ffff
162086:f00::/242086:fff:ffff:ffff:ffff:ffff:ffff:ffff
172086:1000::/242086:10ff:ffff:ffff:ffff:ffff:ffff:ffff
182086:1100::/242086:11ff:ffff:ffff:ffff:ffff:ffff:ffff
192086:1200::/242086:12ff:ffff:ffff:ffff:ffff:ffff:ffff
202086:1300::/242086:13ff:ffff:ffff:ffff:ffff:ffff:ffff
212086:1400::/242086:14ff:ffff:ffff:ffff:ffff:ffff:ffff
222086:1500::/242086:15ff:ffff:ffff:ffff:ffff:ffff:ffff
232086:1600::/242086:16ff:ffff:ffff:ffff:ffff:ffff:ffff
242086:1700::/242086:17ff:ffff:ffff:ffff:ffff:ffff:ffff
252086:1800::/242086:18ff:ffff:ffff:ffff:ffff:ffff:ffff
262086:1900::/242086:19ff:ffff:ffff:ffff:ffff:ffff:ffff
272086:1a00::/242086:1aff:ffff:ffff:ffff:ffff:ffff:ffff
282086:1b00::/242086:1bff:ffff:ffff:ffff:ffff:ffff:ffff
292086:1c00::/242086:1cff:ffff:ffff:ffff:ffff:ffff:ffff
302086:1d00::/242086:1dff:ffff:ffff:ffff:ffff:ffff:ffff
312086:1e00::/242086:1eff:ffff:ffff:ffff:ffff:ffff:ffff
322086:1f00::/242086:1fff:ffff:ffff:ffff:ffff:ffff:ffff
332086:2000::/242086:20ff:ffff:ffff:ffff:ffff:ffff:ffff
342086:2100::/242086:21ff:ffff:ffff:ffff:ffff:ffff:ffff
352086:2200::/242086:22ff:ffff:ffff:ffff:ffff:ffff:ffff
362086:2300::/242086:23ff:ffff:ffff:ffff:ffff:ffff:ffff
372086:2400::/242086:24ff:ffff:ffff:ffff:ffff:ffff:ffff
382086:2500::/242086:25ff:ffff:ffff:ffff:ffff:ffff:ffff
392086:2600::/242086:26ff:ffff:ffff:ffff:ffff:ffff:ffff
402086:2700::/242086:27ff:ffff:ffff:ffff:ffff:ffff:ffff
412086:2800::/242086:28ff:ffff:ffff:ffff:ffff:ffff:ffff
422086:2900::/242086:29ff:ffff:ffff:ffff:ffff:ffff:ffff
432086:2a00::/242086:2aff:ffff:ffff:ffff:ffff:ffff:ffff
442086:2b00::/242086:2bff:ffff:ffff:ffff:ffff:ffff:ffff
452086:2c00::/242086:2cff:ffff:ffff:ffff:ffff:ffff:ffff
462086:2d00::/242086:2dff:ffff:ffff:ffff:ffff:ffff:ffff
472086:2e00::/242086:2eff:ffff:ffff:ffff:ffff:ffff:ffff
482086:2f00::/242086:2fff:ffff:ffff:ffff:ffff:ffff:ffff
492086:3000::/242086:30ff:ffff:ffff:ffff:ffff:ffff:ffff
502086:3100::/242086:31ff:ffff:ffff:ffff:ffff:ffff:ffff
512086:3200::/242086:32ff:ffff:ffff:ffff:ffff:ffff:ffff
522086:3300::/242086:33ff:ffff:ffff:ffff:ffff:ffff:ffff
532086:3400::/242086:34ff:ffff:ffff:ffff:ffff:ffff:ffff
542086:3500::/242086:35ff:ffff:ffff:ffff:ffff:ffff:ffff
552086:3600::/242086:36ff:ffff:ffff:ffff:ffff:ffff:ffff
562086:3700::/242086:37ff:ffff:ffff:ffff:ffff:ffff:ffff
572086:3800::/242086:38ff:ffff:ffff:ffff:ffff:ffff:ffff
582086:3900::/242086:39ff:ffff:ffff:ffff:ffff:ffff:ffff
592086:3a00::/242086:3aff:ffff:ffff:ffff:ffff:ffff:ffff
602086:3b00::/242086:3bff:ffff:ffff:ffff:ffff:ffff:ffff
612086:3c00::/242086:3cff:ffff:ffff:ffff:ffff:ffff:ffff
622086:3d00::/242086:3dff:ffff:ffff:ffff:ffff:ffff:ffff
632086:3e00::/242086:3eff:ffff:ffff:ffff:ffff:ffff:ffff
642086:3f00::/242086:3fff:ffff:ffff:ffff:ffff:ffff:ffff
652086:4000::/242086:40ff:ffff:ffff:ffff:ffff:ffff:ffff
662086:4100::/242086:41ff:ffff:ffff:ffff:ffff:ffff:ffff
672086:4200::/242086:42ff:ffff:ffff:ffff:ffff:ffff:ffff
682086:4300::/242086:43ff:ffff:ffff:ffff:ffff:ffff:ffff
692086:4400::/242086:44ff:ffff:ffff:ffff:ffff:ffff:ffff
702086:4500::/242086:45ff:ffff:ffff:ffff:ffff:ffff:ffff
712086:4600::/242086:46ff:ffff:ffff:ffff:ffff:ffff:ffff
722086:4700::/242086:47ff:ffff:ffff:ffff:ffff:ffff:ffff
732086:4800::/242086:48ff:ffff:ffff:ffff:ffff:ffff:ffff
742086:4900::/242086:49ff:ffff:ffff:ffff:ffff:ffff:ffff
752086:4a00::/242086:4aff:ffff:ffff:ffff:ffff:ffff:ffff
762086:4b00::/242086:4bff:ffff:ffff:ffff:ffff:ffff:ffff
772086:4c00::/242086:4cff:ffff:ffff:ffff:ffff:ffff:ffff
782086:4d00::/242086:4dff:ffff:ffff:ffff:ffff:ffff:ffff
792086:4e00::/242086:4eff:ffff:ffff:ffff:ffff:ffff:ffff
802086:4f00::/242086:4fff:ffff:ffff:ffff:ffff:ffff:ffff
812086:5000::/242086:50ff:ffff:ffff:ffff:ffff:ffff:ffff
822086:5100::/242086:51ff:ffff:ffff:ffff:ffff:ffff:ffff
832086:5200::/242086:52ff:ffff:ffff:ffff:ffff:ffff:ffff
842086:5300::/242086:53ff:ffff:ffff:ffff:ffff:ffff:ffff
852086:5400::/242086:54ff:ffff:ffff:ffff:ffff:ffff:ffff
862086:5500::/242086:55ff:ffff:ffff:ffff:ffff:ffff:ffff
872086:5600::/242086:56ff:ffff:ffff:ffff:ffff:ffff:ffff
882086:5700::/242086:57ff:ffff:ffff:ffff:ffff:ffff:ffff
892086:5800::/242086:58ff:ffff:ffff:ffff:ffff:ffff:ffff
902086:5900::/242086:59ff:ffff:ffff:ffff:ffff:ffff:ffff
912086:5a00::/242086:5aff:ffff:ffff:ffff:ffff:ffff:ffff
922086:5b00::/242086:5bff:ffff:ffff:ffff:ffff:ffff:ffff
932086:5c00::/242086:5cff:ffff:ffff:ffff:ffff:ffff:ffff
942086:5d00::/242086:5dff:ffff:ffff:ffff:ffff:ffff:ffff
952086:5e00::/242086:5eff:ffff:ffff:ffff:ffff:ffff:ffff
962086:5f00::/242086:5fff:ffff:ffff:ffff:ffff:ffff:ffff
972086:6000::/242086:60ff:ffff:ffff:ffff:ffff:ffff:ffff
982086:6100::/242086:61ff:ffff:ffff:ffff:ffff:ffff:ffff
992086:6200::/242086:62ff:ffff:ffff:ffff:ffff:ffff:ffff
1002086:6300::/242086:63ff:ffff:ffff:ffff:ffff:ffff:ffff
1012086:6400::/242086:64ff:ffff:ffff:ffff:ffff:ffff:ffff
1022086:6500::/242086:65ff:ffff:ffff:ffff:ffff:ffff:ffff
1032086:6600::/242086:66ff:ffff:ffff:ffff:ffff:ffff:ffff
1042086:6700::/242086:67ff:ffff:ffff:ffff:ffff:ffff:ffff
1052086:6800::/242086:68ff:ffff:ffff:ffff:ffff:ffff:ffff
1062086:6900::/242086:69ff:ffff:ffff:ffff:ffff:ffff:ffff
1072086:6a00::/242086:6aff:ffff:ffff:ffff:ffff:ffff:ffff
1082086:6b00::/242086:6bff:ffff:ffff:ffff:ffff:ffff:ffff
1092086:6c00::/242086:6cff:ffff:ffff:ffff:ffff:ffff:ffff
1102086:6d00::/242086:6dff:ffff:ffff:ffff:ffff:ffff:ffff
1112086:6e00::/242086:6eff:ffff:ffff:ffff:ffff:ffff:ffff
1122086:6f00::/242086:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1132086:7000::/242086:70ff:ffff:ffff:ffff:ffff:ffff:ffff
1142086:7100::/242086:71ff:ffff:ffff:ffff:ffff:ffff:ffff
1152086:7200::/242086:72ff:ffff:ffff:ffff:ffff:ffff:ffff
1162086:7300::/242086:73ff:ffff:ffff:ffff:ffff:ffff:ffff
1172086:7400::/242086:74ff:ffff:ffff:ffff:ffff:ffff:ffff
1182086:7500::/242086:75ff:ffff:ffff:ffff:ffff:ffff:ffff
1192086:7600::/242086:76ff:ffff:ffff:ffff:ffff:ffff:ffff
1202086:7700::/242086:77ff:ffff:ffff:ffff:ffff:ffff:ffff
1212086:7800::/242086:78ff:ffff:ffff:ffff:ffff:ffff:ffff
1222086:7900::/242086:79ff:ffff:ffff:ffff:ffff:ffff:ffff
1232086:7a00::/242086:7aff:ffff:ffff:ffff:ffff:ffff:ffff
1242086:7b00::/242086:7bff:ffff:ffff:ffff:ffff:ffff:ffff
1252086:7c00::/242086:7cff:ffff:ffff:ffff:ffff:ffff:ffff
1262086:7d00::/242086:7dff:ffff:ffff:ffff:ffff:ffff:ffff
1272086:7e00::/242086:7eff:ffff:ffff:ffff:ffff:ffff:ffff
1282086:7f00::/242086:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1292086:8000::/242086:80ff:ffff:ffff:ffff:ffff:ffff:ffff
1302086:8100::/242086:81ff:ffff:ffff:ffff:ffff:ffff:ffff
1312086:8200::/242086:82ff:ffff:ffff:ffff:ffff:ffff:ffff
1322086:8300::/242086:83ff:ffff:ffff:ffff:ffff:ffff:ffff
1332086:8400::/242086:84ff:ffff:ffff:ffff:ffff:ffff:ffff
1342086:8500::/242086:85ff:ffff:ffff:ffff:ffff:ffff:ffff
1352086:8600::/242086:86ff:ffff:ffff:ffff:ffff:ffff:ffff
1362086:8700::/242086:87ff:ffff:ffff:ffff:ffff:ffff:ffff
1372086:8800::/242086:88ff:ffff:ffff:ffff:ffff:ffff:ffff
1382086:8900::/242086:89ff:ffff:ffff:ffff:ffff:ffff:ffff
1392086:8a00::/242086:8aff:ffff:ffff:ffff:ffff:ffff:ffff
1402086:8b00::/242086:8bff:ffff:ffff:ffff:ffff:ffff:ffff
1412086:8c00::/242086:8cff:ffff:ffff:ffff:ffff:ffff:ffff
1422086:8d00::/242086:8dff:ffff:ffff:ffff:ffff:ffff:ffff
1432086:8e00::/242086:8eff:ffff:ffff:ffff:ffff:ffff:ffff
1442086:8f00::/242086:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1452086:9000::/242086:90ff:ffff:ffff:ffff:ffff:ffff:ffff
1462086:9100::/242086:91ff:ffff:ffff:ffff:ffff:ffff:ffff
1472086:9200::/242086:92ff:ffff:ffff:ffff:ffff:ffff:ffff
1482086:9300::/242086:93ff:ffff:ffff:ffff:ffff:ffff:ffff
1492086:9400::/242086:94ff:ffff:ffff:ffff:ffff:ffff:ffff
1502086:9500::/242086:95ff:ffff:ffff:ffff:ffff:ffff:ffff
1512086:9600::/242086:96ff:ffff:ffff:ffff:ffff:ffff:ffff
1522086:9700::/242086:97ff:ffff:ffff:ffff:ffff:ffff:ffff
1532086:9800::/242086:98ff:ffff:ffff:ffff:ffff:ffff:ffff
1542086:9900::/242086:99ff:ffff:ffff:ffff:ffff:ffff:ffff
1552086:9a00::/242086:9aff:ffff:ffff:ffff:ffff:ffff:ffff
1562086:9b00::/242086:9bff:ffff:ffff:ffff:ffff:ffff:ffff
1572086:9c00::/242086:9cff:ffff:ffff:ffff:ffff:ffff:ffff
1582086:9d00::/242086:9dff:ffff:ffff:ffff:ffff:ffff:ffff
1592086:9e00::/242086:9eff:ffff:ffff:ffff:ffff:ffff:ffff
1602086:9f00::/242086:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1612086:a000::/242086:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
1622086:a100::/242086:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
1632086:a200::/242086:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
1642086:a300::/242086:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
1652086:a400::/242086:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
1662086:a500::/242086:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
1672086:a600::/242086:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
1682086:a700::/242086:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
1692086:a800::/242086:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
1702086:a900::/242086:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
1712086:aa00::/242086:aaff:ffff:ffff:ffff:ffff:ffff:ffff
1722086:ab00::/242086:abff:ffff:ffff:ffff:ffff:ffff:ffff
1732086:ac00::/242086:acff:ffff:ffff:ffff:ffff:ffff:ffff
1742086:ad00::/242086:adff:ffff:ffff:ffff:ffff:ffff:ffff
1752086:ae00::/242086:aeff:ffff:ffff:ffff:ffff:ffff:ffff
1762086:af00::/242086:afff:ffff:ffff:ffff:ffff:ffff:ffff
1772086:b000::/242086:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
1782086:b100::/242086:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
1792086:b200::/242086:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
1802086:b300::/242086:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
1812086:b400::/242086:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
1822086:b500::/242086:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
1832086:b600::/242086:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
1842086:b700::/242086:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
1852086:b800::/242086:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
1862086:b900::/242086:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
1872086:ba00::/242086:baff:ffff:ffff:ffff:ffff:ffff:ffff
1882086:bb00::/242086:bbff:ffff:ffff:ffff:ffff:ffff:ffff
1892086:bc00::/242086:bcff:ffff:ffff:ffff:ffff:ffff:ffff
1902086:bd00::/242086:bdff:ffff:ffff:ffff:ffff:ffff:ffff
1912086:be00::/242086:beff:ffff:ffff:ffff:ffff:ffff:ffff
1922086:bf00::/242086:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1932086:c000::/242086:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
1942086:c100::/242086:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
1952086:c200::/242086:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
1962086:c300::/242086:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
1972086:c400::/242086:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
1982086:c500::/242086:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
1992086:c600::/242086:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
2002086:c700::/242086:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
2012086:c800::/242086:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
2022086:c900::/242086:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
2032086:ca00::/242086:caff:ffff:ffff:ffff:ffff:ffff:ffff
2042086:cb00::/242086:cbff:ffff:ffff:ffff:ffff:ffff:ffff
2052086:cc00::/242086:ccff:ffff:ffff:ffff:ffff:ffff:ffff
2062086:cd00::/242086:cdff:ffff:ffff:ffff:ffff:ffff:ffff
2072086:ce00::/242086:ceff:ffff:ffff:ffff:ffff:ffff:ffff
2082086:cf00::/242086:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2092086:d000::/242086:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
2102086:d100::/242086:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
2112086:d200::/242086:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
2122086:d300::/242086:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
2132086:d400::/242086:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
2142086:d500::/242086:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
2152086:d600::/242086:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
2162086:d700::/242086:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
2172086:d800::/242086:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
2182086:d900::/242086:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
2192086:da00::/242086:daff:ffff:ffff:ffff:ffff:ffff:ffff
2202086:db00::/242086:dbff:ffff:ffff:ffff:ffff:ffff:ffff
2212086:dc00::/242086:dcff:ffff:ffff:ffff:ffff:ffff:ffff
2222086:dd00::/242086:ddff:ffff:ffff:ffff:ffff:ffff:ffff
2232086:de00::/242086:deff:ffff:ffff:ffff:ffff:ffff:ffff
2242086:df00::/242086:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2252086:e000::/242086:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
2262086:e100::/242086:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
2272086:e200::/242086:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
2282086:e300::/242086:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
2292086:e400::/242086:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
2302086:e500::/242086:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
2312086:e600::/242086:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
2322086:e700::/242086:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
2332086:e800::/242086:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
2342086:e900::/242086:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
2352086:ea00::/242086:eaff:ffff:ffff:ffff:ffff:ffff:ffff
2362086:eb00::/242086:ebff:ffff:ffff:ffff:ffff:ffff:ffff
2372086:ec00::/242086:ecff:ffff:ffff:ffff:ffff:ffff:ffff
2382086:ed00::/242086:edff:ffff:ffff:ffff:ffff:ffff:ffff
2392086:ee00::/242086:eeff:ffff:ffff:ffff:ffff:ffff:ffff
2402086:ef00::/242086:efff:ffff:ffff:ffff:ffff:ffff:ffff
2412086:f000::/242086:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
2422086:f100::/242086:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
2432086:f200::/242086:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
2442086:f300::/242086:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
2452086:f400::/242086:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
2462086:f500::/242086:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
2472086:f600::/242086:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
2482086:f700::/242086:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
2492086:f800::/242086:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
2502086:f900::/242086:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
2512086:fa00::/242086:faff:ffff:ffff:ffff:ffff:ffff:ffff
2522086:fb00::/242086:fbff:ffff:ffff:ffff:ffff:ffff:ffff
2532086:fc00::/242086:fcff:ffff:ffff:ffff:ffff:ffff:ffff
2542086:fd00::/242086:fdff:ffff:ffff:ffff:ffff:ffff:ffff
2552086:fe00::/242086:feff:ffff:ffff:ffff:ffff:ffff:ffff
2562086:ff00::/242086: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.