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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
2089::/16
First address
2089::
Last address
2089: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
2089:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
9.8.0.2.ip6.arpa
Split into smaller subnets/24
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

2089::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
12089::/242089:ff:ffff:ffff:ffff:ffff:ffff:ffff
22089:100::/242089:1ff:ffff:ffff:ffff:ffff:ffff:ffff
32089:200::/242089:2ff:ffff:ffff:ffff:ffff:ffff:ffff
42089:300::/242089:3ff:ffff:ffff:ffff:ffff:ffff:ffff
52089:400::/242089:4ff:ffff:ffff:ffff:ffff:ffff:ffff
62089:500::/242089:5ff:ffff:ffff:ffff:ffff:ffff:ffff
72089:600::/242089:6ff:ffff:ffff:ffff:ffff:ffff:ffff
82089:700::/242089:7ff:ffff:ffff:ffff:ffff:ffff:ffff
92089:800::/242089:8ff:ffff:ffff:ffff:ffff:ffff:ffff
102089:900::/242089:9ff:ffff:ffff:ffff:ffff:ffff:ffff
112089:a00::/242089:aff:ffff:ffff:ffff:ffff:ffff:ffff
122089:b00::/242089:bff:ffff:ffff:ffff:ffff:ffff:ffff
132089:c00::/242089:cff:ffff:ffff:ffff:ffff:ffff:ffff
142089:d00::/242089:dff:ffff:ffff:ffff:ffff:ffff:ffff
152089:e00::/242089:eff:ffff:ffff:ffff:ffff:ffff:ffff
162089:f00::/242089:fff:ffff:ffff:ffff:ffff:ffff:ffff
172089:1000::/242089:10ff:ffff:ffff:ffff:ffff:ffff:ffff
182089:1100::/242089:11ff:ffff:ffff:ffff:ffff:ffff:ffff
192089:1200::/242089:12ff:ffff:ffff:ffff:ffff:ffff:ffff
202089:1300::/242089:13ff:ffff:ffff:ffff:ffff:ffff:ffff
212089:1400::/242089:14ff:ffff:ffff:ffff:ffff:ffff:ffff
222089:1500::/242089:15ff:ffff:ffff:ffff:ffff:ffff:ffff
232089:1600::/242089:16ff:ffff:ffff:ffff:ffff:ffff:ffff
242089:1700::/242089:17ff:ffff:ffff:ffff:ffff:ffff:ffff
252089:1800::/242089:18ff:ffff:ffff:ffff:ffff:ffff:ffff
262089:1900::/242089:19ff:ffff:ffff:ffff:ffff:ffff:ffff
272089:1a00::/242089:1aff:ffff:ffff:ffff:ffff:ffff:ffff
282089:1b00::/242089:1bff:ffff:ffff:ffff:ffff:ffff:ffff
292089:1c00::/242089:1cff:ffff:ffff:ffff:ffff:ffff:ffff
302089:1d00::/242089:1dff:ffff:ffff:ffff:ffff:ffff:ffff
312089:1e00::/242089:1eff:ffff:ffff:ffff:ffff:ffff:ffff
322089:1f00::/242089:1fff:ffff:ffff:ffff:ffff:ffff:ffff
332089:2000::/242089:20ff:ffff:ffff:ffff:ffff:ffff:ffff
342089:2100::/242089:21ff:ffff:ffff:ffff:ffff:ffff:ffff
352089:2200::/242089:22ff:ffff:ffff:ffff:ffff:ffff:ffff
362089:2300::/242089:23ff:ffff:ffff:ffff:ffff:ffff:ffff
372089:2400::/242089:24ff:ffff:ffff:ffff:ffff:ffff:ffff
382089:2500::/242089:25ff:ffff:ffff:ffff:ffff:ffff:ffff
392089:2600::/242089:26ff:ffff:ffff:ffff:ffff:ffff:ffff
402089:2700::/242089:27ff:ffff:ffff:ffff:ffff:ffff:ffff
412089:2800::/242089:28ff:ffff:ffff:ffff:ffff:ffff:ffff
422089:2900::/242089:29ff:ffff:ffff:ffff:ffff:ffff:ffff
432089:2a00::/242089:2aff:ffff:ffff:ffff:ffff:ffff:ffff
442089:2b00::/242089:2bff:ffff:ffff:ffff:ffff:ffff:ffff
452089:2c00::/242089:2cff:ffff:ffff:ffff:ffff:ffff:ffff
462089:2d00::/242089:2dff:ffff:ffff:ffff:ffff:ffff:ffff
472089:2e00::/242089:2eff:ffff:ffff:ffff:ffff:ffff:ffff
482089:2f00::/242089:2fff:ffff:ffff:ffff:ffff:ffff:ffff
492089:3000::/242089:30ff:ffff:ffff:ffff:ffff:ffff:ffff
502089:3100::/242089:31ff:ffff:ffff:ffff:ffff:ffff:ffff
512089:3200::/242089:32ff:ffff:ffff:ffff:ffff:ffff:ffff
522089:3300::/242089:33ff:ffff:ffff:ffff:ffff:ffff:ffff
532089:3400::/242089:34ff:ffff:ffff:ffff:ffff:ffff:ffff
542089:3500::/242089:35ff:ffff:ffff:ffff:ffff:ffff:ffff
552089:3600::/242089:36ff:ffff:ffff:ffff:ffff:ffff:ffff
562089:3700::/242089:37ff:ffff:ffff:ffff:ffff:ffff:ffff
572089:3800::/242089:38ff:ffff:ffff:ffff:ffff:ffff:ffff
582089:3900::/242089:39ff:ffff:ffff:ffff:ffff:ffff:ffff
592089:3a00::/242089:3aff:ffff:ffff:ffff:ffff:ffff:ffff
602089:3b00::/242089:3bff:ffff:ffff:ffff:ffff:ffff:ffff
612089:3c00::/242089:3cff:ffff:ffff:ffff:ffff:ffff:ffff
622089:3d00::/242089:3dff:ffff:ffff:ffff:ffff:ffff:ffff
632089:3e00::/242089:3eff:ffff:ffff:ffff:ffff:ffff:ffff
642089:3f00::/242089:3fff:ffff:ffff:ffff:ffff:ffff:ffff
652089:4000::/242089:40ff:ffff:ffff:ffff:ffff:ffff:ffff
662089:4100::/242089:41ff:ffff:ffff:ffff:ffff:ffff:ffff
672089:4200::/242089:42ff:ffff:ffff:ffff:ffff:ffff:ffff
682089:4300::/242089:43ff:ffff:ffff:ffff:ffff:ffff:ffff
692089:4400::/242089:44ff:ffff:ffff:ffff:ffff:ffff:ffff
702089:4500::/242089:45ff:ffff:ffff:ffff:ffff:ffff:ffff
712089:4600::/242089:46ff:ffff:ffff:ffff:ffff:ffff:ffff
722089:4700::/242089:47ff:ffff:ffff:ffff:ffff:ffff:ffff
732089:4800::/242089:48ff:ffff:ffff:ffff:ffff:ffff:ffff
742089:4900::/242089:49ff:ffff:ffff:ffff:ffff:ffff:ffff
752089:4a00::/242089:4aff:ffff:ffff:ffff:ffff:ffff:ffff
762089:4b00::/242089:4bff:ffff:ffff:ffff:ffff:ffff:ffff
772089:4c00::/242089:4cff:ffff:ffff:ffff:ffff:ffff:ffff
782089:4d00::/242089:4dff:ffff:ffff:ffff:ffff:ffff:ffff
792089:4e00::/242089:4eff:ffff:ffff:ffff:ffff:ffff:ffff
802089:4f00::/242089:4fff:ffff:ffff:ffff:ffff:ffff:ffff
812089:5000::/242089:50ff:ffff:ffff:ffff:ffff:ffff:ffff
822089:5100::/242089:51ff:ffff:ffff:ffff:ffff:ffff:ffff
832089:5200::/242089:52ff:ffff:ffff:ffff:ffff:ffff:ffff
842089:5300::/242089:53ff:ffff:ffff:ffff:ffff:ffff:ffff
852089:5400::/242089:54ff:ffff:ffff:ffff:ffff:ffff:ffff
862089:5500::/242089:55ff:ffff:ffff:ffff:ffff:ffff:ffff
872089:5600::/242089:56ff:ffff:ffff:ffff:ffff:ffff:ffff
882089:5700::/242089:57ff:ffff:ffff:ffff:ffff:ffff:ffff
892089:5800::/242089:58ff:ffff:ffff:ffff:ffff:ffff:ffff
902089:5900::/242089:59ff:ffff:ffff:ffff:ffff:ffff:ffff
912089:5a00::/242089:5aff:ffff:ffff:ffff:ffff:ffff:ffff
922089:5b00::/242089:5bff:ffff:ffff:ffff:ffff:ffff:ffff
932089:5c00::/242089:5cff:ffff:ffff:ffff:ffff:ffff:ffff
942089:5d00::/242089:5dff:ffff:ffff:ffff:ffff:ffff:ffff
952089:5e00::/242089:5eff:ffff:ffff:ffff:ffff:ffff:ffff
962089:5f00::/242089:5fff:ffff:ffff:ffff:ffff:ffff:ffff
972089:6000::/242089:60ff:ffff:ffff:ffff:ffff:ffff:ffff
982089:6100::/242089:61ff:ffff:ffff:ffff:ffff:ffff:ffff
992089:6200::/242089:62ff:ffff:ffff:ffff:ffff:ffff:ffff
1002089:6300::/242089:63ff:ffff:ffff:ffff:ffff:ffff:ffff
1012089:6400::/242089:64ff:ffff:ffff:ffff:ffff:ffff:ffff
1022089:6500::/242089:65ff:ffff:ffff:ffff:ffff:ffff:ffff
1032089:6600::/242089:66ff:ffff:ffff:ffff:ffff:ffff:ffff
1042089:6700::/242089:67ff:ffff:ffff:ffff:ffff:ffff:ffff
1052089:6800::/242089:68ff:ffff:ffff:ffff:ffff:ffff:ffff
1062089:6900::/242089:69ff:ffff:ffff:ffff:ffff:ffff:ffff
1072089:6a00::/242089:6aff:ffff:ffff:ffff:ffff:ffff:ffff
1082089:6b00::/242089:6bff:ffff:ffff:ffff:ffff:ffff:ffff
1092089:6c00::/242089:6cff:ffff:ffff:ffff:ffff:ffff:ffff
1102089:6d00::/242089:6dff:ffff:ffff:ffff:ffff:ffff:ffff
1112089:6e00::/242089:6eff:ffff:ffff:ffff:ffff:ffff:ffff
1122089:6f00::/242089:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1132089:7000::/242089:70ff:ffff:ffff:ffff:ffff:ffff:ffff
1142089:7100::/242089:71ff:ffff:ffff:ffff:ffff:ffff:ffff
1152089:7200::/242089:72ff:ffff:ffff:ffff:ffff:ffff:ffff
1162089:7300::/242089:73ff:ffff:ffff:ffff:ffff:ffff:ffff
1172089:7400::/242089:74ff:ffff:ffff:ffff:ffff:ffff:ffff
1182089:7500::/242089:75ff:ffff:ffff:ffff:ffff:ffff:ffff
1192089:7600::/242089:76ff:ffff:ffff:ffff:ffff:ffff:ffff
1202089:7700::/242089:77ff:ffff:ffff:ffff:ffff:ffff:ffff
1212089:7800::/242089:78ff:ffff:ffff:ffff:ffff:ffff:ffff
1222089:7900::/242089:79ff:ffff:ffff:ffff:ffff:ffff:ffff
1232089:7a00::/242089:7aff:ffff:ffff:ffff:ffff:ffff:ffff
1242089:7b00::/242089:7bff:ffff:ffff:ffff:ffff:ffff:ffff
1252089:7c00::/242089:7cff:ffff:ffff:ffff:ffff:ffff:ffff
1262089:7d00::/242089:7dff:ffff:ffff:ffff:ffff:ffff:ffff
1272089:7e00::/242089:7eff:ffff:ffff:ffff:ffff:ffff:ffff
1282089:7f00::/242089:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1292089:8000::/242089:80ff:ffff:ffff:ffff:ffff:ffff:ffff
1302089:8100::/242089:81ff:ffff:ffff:ffff:ffff:ffff:ffff
1312089:8200::/242089:82ff:ffff:ffff:ffff:ffff:ffff:ffff
1322089:8300::/242089:83ff:ffff:ffff:ffff:ffff:ffff:ffff
1332089:8400::/242089:84ff:ffff:ffff:ffff:ffff:ffff:ffff
1342089:8500::/242089:85ff:ffff:ffff:ffff:ffff:ffff:ffff
1352089:8600::/242089:86ff:ffff:ffff:ffff:ffff:ffff:ffff
1362089:8700::/242089:87ff:ffff:ffff:ffff:ffff:ffff:ffff
1372089:8800::/242089:88ff:ffff:ffff:ffff:ffff:ffff:ffff
1382089:8900::/242089:89ff:ffff:ffff:ffff:ffff:ffff:ffff
1392089:8a00::/242089:8aff:ffff:ffff:ffff:ffff:ffff:ffff
1402089:8b00::/242089:8bff:ffff:ffff:ffff:ffff:ffff:ffff
1412089:8c00::/242089:8cff:ffff:ffff:ffff:ffff:ffff:ffff
1422089:8d00::/242089:8dff:ffff:ffff:ffff:ffff:ffff:ffff
1432089:8e00::/242089:8eff:ffff:ffff:ffff:ffff:ffff:ffff
1442089:8f00::/242089:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1452089:9000::/242089:90ff:ffff:ffff:ffff:ffff:ffff:ffff
1462089:9100::/242089:91ff:ffff:ffff:ffff:ffff:ffff:ffff
1472089:9200::/242089:92ff:ffff:ffff:ffff:ffff:ffff:ffff
1482089:9300::/242089:93ff:ffff:ffff:ffff:ffff:ffff:ffff
1492089:9400::/242089:94ff:ffff:ffff:ffff:ffff:ffff:ffff
1502089:9500::/242089:95ff:ffff:ffff:ffff:ffff:ffff:ffff
1512089:9600::/242089:96ff:ffff:ffff:ffff:ffff:ffff:ffff
1522089:9700::/242089:97ff:ffff:ffff:ffff:ffff:ffff:ffff
1532089:9800::/242089:98ff:ffff:ffff:ffff:ffff:ffff:ffff
1542089:9900::/242089:99ff:ffff:ffff:ffff:ffff:ffff:ffff
1552089:9a00::/242089:9aff:ffff:ffff:ffff:ffff:ffff:ffff
1562089:9b00::/242089:9bff:ffff:ffff:ffff:ffff:ffff:ffff
1572089:9c00::/242089:9cff:ffff:ffff:ffff:ffff:ffff:ffff
1582089:9d00::/242089:9dff:ffff:ffff:ffff:ffff:ffff:ffff
1592089:9e00::/242089:9eff:ffff:ffff:ffff:ffff:ffff:ffff
1602089:9f00::/242089:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1612089:a000::/242089:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
1622089:a100::/242089:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
1632089:a200::/242089:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
1642089:a300::/242089:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
1652089:a400::/242089:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
1662089:a500::/242089:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
1672089:a600::/242089:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
1682089:a700::/242089:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
1692089:a800::/242089:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
1702089:a900::/242089:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
1712089:aa00::/242089:aaff:ffff:ffff:ffff:ffff:ffff:ffff
1722089:ab00::/242089:abff:ffff:ffff:ffff:ffff:ffff:ffff
1732089:ac00::/242089:acff:ffff:ffff:ffff:ffff:ffff:ffff
1742089:ad00::/242089:adff:ffff:ffff:ffff:ffff:ffff:ffff
1752089:ae00::/242089:aeff:ffff:ffff:ffff:ffff:ffff:ffff
1762089:af00::/242089:afff:ffff:ffff:ffff:ffff:ffff:ffff
1772089:b000::/242089:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
1782089:b100::/242089:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
1792089:b200::/242089:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
1802089:b300::/242089:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
1812089:b400::/242089:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
1822089:b500::/242089:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
1832089:b600::/242089:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
1842089:b700::/242089:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
1852089:b800::/242089:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
1862089:b900::/242089:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
1872089:ba00::/242089:baff:ffff:ffff:ffff:ffff:ffff:ffff
1882089:bb00::/242089:bbff:ffff:ffff:ffff:ffff:ffff:ffff
1892089:bc00::/242089:bcff:ffff:ffff:ffff:ffff:ffff:ffff
1902089:bd00::/242089:bdff:ffff:ffff:ffff:ffff:ffff:ffff
1912089:be00::/242089:beff:ffff:ffff:ffff:ffff:ffff:ffff
1922089:bf00::/242089:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1932089:c000::/242089:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
1942089:c100::/242089:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
1952089:c200::/242089:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
1962089:c300::/242089:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
1972089:c400::/242089:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
1982089:c500::/242089:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
1992089:c600::/242089:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
2002089:c700::/242089:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
2012089:c800::/242089:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
2022089:c900::/242089:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
2032089:ca00::/242089:caff:ffff:ffff:ffff:ffff:ffff:ffff
2042089:cb00::/242089:cbff:ffff:ffff:ffff:ffff:ffff:ffff
2052089:cc00::/242089:ccff:ffff:ffff:ffff:ffff:ffff:ffff
2062089:cd00::/242089:cdff:ffff:ffff:ffff:ffff:ffff:ffff
2072089:ce00::/242089:ceff:ffff:ffff:ffff:ffff:ffff:ffff
2082089:cf00::/242089:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2092089:d000::/242089:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
2102089:d100::/242089:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
2112089:d200::/242089:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
2122089:d300::/242089:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
2132089:d400::/242089:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
2142089:d500::/242089:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
2152089:d600::/242089:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
2162089:d700::/242089:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
2172089:d800::/242089:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
2182089:d900::/242089:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
2192089:da00::/242089:daff:ffff:ffff:ffff:ffff:ffff:ffff
2202089:db00::/242089:dbff:ffff:ffff:ffff:ffff:ffff:ffff
2212089:dc00::/242089:dcff:ffff:ffff:ffff:ffff:ffff:ffff
2222089:dd00::/242089:ddff:ffff:ffff:ffff:ffff:ffff:ffff
2232089:de00::/242089:deff:ffff:ffff:ffff:ffff:ffff:ffff
2242089:df00::/242089:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2252089:e000::/242089:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
2262089:e100::/242089:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
2272089:e200::/242089:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
2282089:e300::/242089:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
2292089:e400::/242089:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
2302089:e500::/242089:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
2312089:e600::/242089:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
2322089:e700::/242089:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
2332089:e800::/242089:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
2342089:e900::/242089:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
2352089:ea00::/242089:eaff:ffff:ffff:ffff:ffff:ffff:ffff
2362089:eb00::/242089:ebff:ffff:ffff:ffff:ffff:ffff:ffff
2372089:ec00::/242089:ecff:ffff:ffff:ffff:ffff:ffff:ffff
2382089:ed00::/242089:edff:ffff:ffff:ffff:ffff:ffff:ffff
2392089:ee00::/242089:eeff:ffff:ffff:ffff:ffff:ffff:ffff
2402089:ef00::/242089:efff:ffff:ffff:ffff:ffff:ffff:ffff
2412089:f000::/242089:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
2422089:f100::/242089:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
2432089:f200::/242089:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
2442089:f300::/242089:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
2452089:f400::/242089:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
2462089:f500::/242089:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
2472089:f600::/242089:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
2482089:f700::/242089:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
2492089:f800::/242089:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
2502089:f900::/242089:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
2512089:fa00::/242089:faff:ffff:ffff:ffff:ffff:ffff:ffff
2522089:fb00::/242089:fbff:ffff:ffff:ffff:ffff:ffff:ffff
2532089:fc00::/242089:fcff:ffff:ffff:ffff:ffff:ffff:ffff
2542089:fd00::/242089:fdff:ffff:ffff:ffff:ffff:ffff:ffff
2552089:fe00::/242089:feff:ffff:ffff:ffff:ffff:ffff:ffff
2562089:ff00::/242089: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.