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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
2046::/16
First address
2046::
Last address
2046: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
2046:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
6.4.0.2.ip6.arpa
Split into smaller subnets/24
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

2046::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
12046::/242046:ff:ffff:ffff:ffff:ffff:ffff:ffff
22046:100::/242046:1ff:ffff:ffff:ffff:ffff:ffff:ffff
32046:200::/242046:2ff:ffff:ffff:ffff:ffff:ffff:ffff
42046:300::/242046:3ff:ffff:ffff:ffff:ffff:ffff:ffff
52046:400::/242046:4ff:ffff:ffff:ffff:ffff:ffff:ffff
62046:500::/242046:5ff:ffff:ffff:ffff:ffff:ffff:ffff
72046:600::/242046:6ff:ffff:ffff:ffff:ffff:ffff:ffff
82046:700::/242046:7ff:ffff:ffff:ffff:ffff:ffff:ffff
92046:800::/242046:8ff:ffff:ffff:ffff:ffff:ffff:ffff
102046:900::/242046:9ff:ffff:ffff:ffff:ffff:ffff:ffff
112046:a00::/242046:aff:ffff:ffff:ffff:ffff:ffff:ffff
122046:b00::/242046:bff:ffff:ffff:ffff:ffff:ffff:ffff
132046:c00::/242046:cff:ffff:ffff:ffff:ffff:ffff:ffff
142046:d00::/242046:dff:ffff:ffff:ffff:ffff:ffff:ffff
152046:e00::/242046:eff:ffff:ffff:ffff:ffff:ffff:ffff
162046:f00::/242046:fff:ffff:ffff:ffff:ffff:ffff:ffff
172046:1000::/242046:10ff:ffff:ffff:ffff:ffff:ffff:ffff
182046:1100::/242046:11ff:ffff:ffff:ffff:ffff:ffff:ffff
192046:1200::/242046:12ff:ffff:ffff:ffff:ffff:ffff:ffff
202046:1300::/242046:13ff:ffff:ffff:ffff:ffff:ffff:ffff
212046:1400::/242046:14ff:ffff:ffff:ffff:ffff:ffff:ffff
222046:1500::/242046:15ff:ffff:ffff:ffff:ffff:ffff:ffff
232046:1600::/242046:16ff:ffff:ffff:ffff:ffff:ffff:ffff
242046:1700::/242046:17ff:ffff:ffff:ffff:ffff:ffff:ffff
252046:1800::/242046:18ff:ffff:ffff:ffff:ffff:ffff:ffff
262046:1900::/242046:19ff:ffff:ffff:ffff:ffff:ffff:ffff
272046:1a00::/242046:1aff:ffff:ffff:ffff:ffff:ffff:ffff
282046:1b00::/242046:1bff:ffff:ffff:ffff:ffff:ffff:ffff
292046:1c00::/242046:1cff:ffff:ffff:ffff:ffff:ffff:ffff
302046:1d00::/242046:1dff:ffff:ffff:ffff:ffff:ffff:ffff
312046:1e00::/242046:1eff:ffff:ffff:ffff:ffff:ffff:ffff
322046:1f00::/242046:1fff:ffff:ffff:ffff:ffff:ffff:ffff
332046:2000::/242046:20ff:ffff:ffff:ffff:ffff:ffff:ffff
342046:2100::/242046:21ff:ffff:ffff:ffff:ffff:ffff:ffff
352046:2200::/242046:22ff:ffff:ffff:ffff:ffff:ffff:ffff
362046:2300::/242046:23ff:ffff:ffff:ffff:ffff:ffff:ffff
372046:2400::/242046:24ff:ffff:ffff:ffff:ffff:ffff:ffff
382046:2500::/242046:25ff:ffff:ffff:ffff:ffff:ffff:ffff
392046:2600::/242046:26ff:ffff:ffff:ffff:ffff:ffff:ffff
402046:2700::/242046:27ff:ffff:ffff:ffff:ffff:ffff:ffff
412046:2800::/242046:28ff:ffff:ffff:ffff:ffff:ffff:ffff
422046:2900::/242046:29ff:ffff:ffff:ffff:ffff:ffff:ffff
432046:2a00::/242046:2aff:ffff:ffff:ffff:ffff:ffff:ffff
442046:2b00::/242046:2bff:ffff:ffff:ffff:ffff:ffff:ffff
452046:2c00::/242046:2cff:ffff:ffff:ffff:ffff:ffff:ffff
462046:2d00::/242046:2dff:ffff:ffff:ffff:ffff:ffff:ffff
472046:2e00::/242046:2eff:ffff:ffff:ffff:ffff:ffff:ffff
482046:2f00::/242046:2fff:ffff:ffff:ffff:ffff:ffff:ffff
492046:3000::/242046:30ff:ffff:ffff:ffff:ffff:ffff:ffff
502046:3100::/242046:31ff:ffff:ffff:ffff:ffff:ffff:ffff
512046:3200::/242046:32ff:ffff:ffff:ffff:ffff:ffff:ffff
522046:3300::/242046:33ff:ffff:ffff:ffff:ffff:ffff:ffff
532046:3400::/242046:34ff:ffff:ffff:ffff:ffff:ffff:ffff
542046:3500::/242046:35ff:ffff:ffff:ffff:ffff:ffff:ffff
552046:3600::/242046:36ff:ffff:ffff:ffff:ffff:ffff:ffff
562046:3700::/242046:37ff:ffff:ffff:ffff:ffff:ffff:ffff
572046:3800::/242046:38ff:ffff:ffff:ffff:ffff:ffff:ffff
582046:3900::/242046:39ff:ffff:ffff:ffff:ffff:ffff:ffff
592046:3a00::/242046:3aff:ffff:ffff:ffff:ffff:ffff:ffff
602046:3b00::/242046:3bff:ffff:ffff:ffff:ffff:ffff:ffff
612046:3c00::/242046:3cff:ffff:ffff:ffff:ffff:ffff:ffff
622046:3d00::/242046:3dff:ffff:ffff:ffff:ffff:ffff:ffff
632046:3e00::/242046:3eff:ffff:ffff:ffff:ffff:ffff:ffff
642046:3f00::/242046:3fff:ffff:ffff:ffff:ffff:ffff:ffff
652046:4000::/242046:40ff:ffff:ffff:ffff:ffff:ffff:ffff
662046:4100::/242046:41ff:ffff:ffff:ffff:ffff:ffff:ffff
672046:4200::/242046:42ff:ffff:ffff:ffff:ffff:ffff:ffff
682046:4300::/242046:43ff:ffff:ffff:ffff:ffff:ffff:ffff
692046:4400::/242046:44ff:ffff:ffff:ffff:ffff:ffff:ffff
702046:4500::/242046:45ff:ffff:ffff:ffff:ffff:ffff:ffff
712046:4600::/242046:46ff:ffff:ffff:ffff:ffff:ffff:ffff
722046:4700::/242046:47ff:ffff:ffff:ffff:ffff:ffff:ffff
732046:4800::/242046:48ff:ffff:ffff:ffff:ffff:ffff:ffff
742046:4900::/242046:49ff:ffff:ffff:ffff:ffff:ffff:ffff
752046:4a00::/242046:4aff:ffff:ffff:ffff:ffff:ffff:ffff
762046:4b00::/242046:4bff:ffff:ffff:ffff:ffff:ffff:ffff
772046:4c00::/242046:4cff:ffff:ffff:ffff:ffff:ffff:ffff
782046:4d00::/242046:4dff:ffff:ffff:ffff:ffff:ffff:ffff
792046:4e00::/242046:4eff:ffff:ffff:ffff:ffff:ffff:ffff
802046:4f00::/242046:4fff:ffff:ffff:ffff:ffff:ffff:ffff
812046:5000::/242046:50ff:ffff:ffff:ffff:ffff:ffff:ffff
822046:5100::/242046:51ff:ffff:ffff:ffff:ffff:ffff:ffff
832046:5200::/242046:52ff:ffff:ffff:ffff:ffff:ffff:ffff
842046:5300::/242046:53ff:ffff:ffff:ffff:ffff:ffff:ffff
852046:5400::/242046:54ff:ffff:ffff:ffff:ffff:ffff:ffff
862046:5500::/242046:55ff:ffff:ffff:ffff:ffff:ffff:ffff
872046:5600::/242046:56ff:ffff:ffff:ffff:ffff:ffff:ffff
882046:5700::/242046:57ff:ffff:ffff:ffff:ffff:ffff:ffff
892046:5800::/242046:58ff:ffff:ffff:ffff:ffff:ffff:ffff
902046:5900::/242046:59ff:ffff:ffff:ffff:ffff:ffff:ffff
912046:5a00::/242046:5aff:ffff:ffff:ffff:ffff:ffff:ffff
922046:5b00::/242046:5bff:ffff:ffff:ffff:ffff:ffff:ffff
932046:5c00::/242046:5cff:ffff:ffff:ffff:ffff:ffff:ffff
942046:5d00::/242046:5dff:ffff:ffff:ffff:ffff:ffff:ffff
952046:5e00::/242046:5eff:ffff:ffff:ffff:ffff:ffff:ffff
962046:5f00::/242046:5fff:ffff:ffff:ffff:ffff:ffff:ffff
972046:6000::/242046:60ff:ffff:ffff:ffff:ffff:ffff:ffff
982046:6100::/242046:61ff:ffff:ffff:ffff:ffff:ffff:ffff
992046:6200::/242046:62ff:ffff:ffff:ffff:ffff:ffff:ffff
1002046:6300::/242046:63ff:ffff:ffff:ffff:ffff:ffff:ffff
1012046:6400::/242046:64ff:ffff:ffff:ffff:ffff:ffff:ffff
1022046:6500::/242046:65ff:ffff:ffff:ffff:ffff:ffff:ffff
1032046:6600::/242046:66ff:ffff:ffff:ffff:ffff:ffff:ffff
1042046:6700::/242046:67ff:ffff:ffff:ffff:ffff:ffff:ffff
1052046:6800::/242046:68ff:ffff:ffff:ffff:ffff:ffff:ffff
1062046:6900::/242046:69ff:ffff:ffff:ffff:ffff:ffff:ffff
1072046:6a00::/242046:6aff:ffff:ffff:ffff:ffff:ffff:ffff
1082046:6b00::/242046:6bff:ffff:ffff:ffff:ffff:ffff:ffff
1092046:6c00::/242046:6cff:ffff:ffff:ffff:ffff:ffff:ffff
1102046:6d00::/242046:6dff:ffff:ffff:ffff:ffff:ffff:ffff
1112046:6e00::/242046:6eff:ffff:ffff:ffff:ffff:ffff:ffff
1122046:6f00::/242046:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1132046:7000::/242046:70ff:ffff:ffff:ffff:ffff:ffff:ffff
1142046:7100::/242046:71ff:ffff:ffff:ffff:ffff:ffff:ffff
1152046:7200::/242046:72ff:ffff:ffff:ffff:ffff:ffff:ffff
1162046:7300::/242046:73ff:ffff:ffff:ffff:ffff:ffff:ffff
1172046:7400::/242046:74ff:ffff:ffff:ffff:ffff:ffff:ffff
1182046:7500::/242046:75ff:ffff:ffff:ffff:ffff:ffff:ffff
1192046:7600::/242046:76ff:ffff:ffff:ffff:ffff:ffff:ffff
1202046:7700::/242046:77ff:ffff:ffff:ffff:ffff:ffff:ffff
1212046:7800::/242046:78ff:ffff:ffff:ffff:ffff:ffff:ffff
1222046:7900::/242046:79ff:ffff:ffff:ffff:ffff:ffff:ffff
1232046:7a00::/242046:7aff:ffff:ffff:ffff:ffff:ffff:ffff
1242046:7b00::/242046:7bff:ffff:ffff:ffff:ffff:ffff:ffff
1252046:7c00::/242046:7cff:ffff:ffff:ffff:ffff:ffff:ffff
1262046:7d00::/242046:7dff:ffff:ffff:ffff:ffff:ffff:ffff
1272046:7e00::/242046:7eff:ffff:ffff:ffff:ffff:ffff:ffff
1282046:7f00::/242046:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1292046:8000::/242046:80ff:ffff:ffff:ffff:ffff:ffff:ffff
1302046:8100::/242046:81ff:ffff:ffff:ffff:ffff:ffff:ffff
1312046:8200::/242046:82ff:ffff:ffff:ffff:ffff:ffff:ffff
1322046:8300::/242046:83ff:ffff:ffff:ffff:ffff:ffff:ffff
1332046:8400::/242046:84ff:ffff:ffff:ffff:ffff:ffff:ffff
1342046:8500::/242046:85ff:ffff:ffff:ffff:ffff:ffff:ffff
1352046:8600::/242046:86ff:ffff:ffff:ffff:ffff:ffff:ffff
1362046:8700::/242046:87ff:ffff:ffff:ffff:ffff:ffff:ffff
1372046:8800::/242046:88ff:ffff:ffff:ffff:ffff:ffff:ffff
1382046:8900::/242046:89ff:ffff:ffff:ffff:ffff:ffff:ffff
1392046:8a00::/242046:8aff:ffff:ffff:ffff:ffff:ffff:ffff
1402046:8b00::/242046:8bff:ffff:ffff:ffff:ffff:ffff:ffff
1412046:8c00::/242046:8cff:ffff:ffff:ffff:ffff:ffff:ffff
1422046:8d00::/242046:8dff:ffff:ffff:ffff:ffff:ffff:ffff
1432046:8e00::/242046:8eff:ffff:ffff:ffff:ffff:ffff:ffff
1442046:8f00::/242046:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1452046:9000::/242046:90ff:ffff:ffff:ffff:ffff:ffff:ffff
1462046:9100::/242046:91ff:ffff:ffff:ffff:ffff:ffff:ffff
1472046:9200::/242046:92ff:ffff:ffff:ffff:ffff:ffff:ffff
1482046:9300::/242046:93ff:ffff:ffff:ffff:ffff:ffff:ffff
1492046:9400::/242046:94ff:ffff:ffff:ffff:ffff:ffff:ffff
1502046:9500::/242046:95ff:ffff:ffff:ffff:ffff:ffff:ffff
1512046:9600::/242046:96ff:ffff:ffff:ffff:ffff:ffff:ffff
1522046:9700::/242046:97ff:ffff:ffff:ffff:ffff:ffff:ffff
1532046:9800::/242046:98ff:ffff:ffff:ffff:ffff:ffff:ffff
1542046:9900::/242046:99ff:ffff:ffff:ffff:ffff:ffff:ffff
1552046:9a00::/242046:9aff:ffff:ffff:ffff:ffff:ffff:ffff
1562046:9b00::/242046:9bff:ffff:ffff:ffff:ffff:ffff:ffff
1572046:9c00::/242046:9cff:ffff:ffff:ffff:ffff:ffff:ffff
1582046:9d00::/242046:9dff:ffff:ffff:ffff:ffff:ffff:ffff
1592046:9e00::/242046:9eff:ffff:ffff:ffff:ffff:ffff:ffff
1602046:9f00::/242046:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1612046:a000::/242046:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
1622046:a100::/242046:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
1632046:a200::/242046:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
1642046:a300::/242046:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
1652046:a400::/242046:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
1662046:a500::/242046:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
1672046:a600::/242046:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
1682046:a700::/242046:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
1692046:a800::/242046:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
1702046:a900::/242046:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
1712046:aa00::/242046:aaff:ffff:ffff:ffff:ffff:ffff:ffff
1722046:ab00::/242046:abff:ffff:ffff:ffff:ffff:ffff:ffff
1732046:ac00::/242046:acff:ffff:ffff:ffff:ffff:ffff:ffff
1742046:ad00::/242046:adff:ffff:ffff:ffff:ffff:ffff:ffff
1752046:ae00::/242046:aeff:ffff:ffff:ffff:ffff:ffff:ffff
1762046:af00::/242046:afff:ffff:ffff:ffff:ffff:ffff:ffff
1772046:b000::/242046:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
1782046:b100::/242046:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
1792046:b200::/242046:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
1802046:b300::/242046:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
1812046:b400::/242046:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
1822046:b500::/242046:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
1832046:b600::/242046:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
1842046:b700::/242046:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
1852046:b800::/242046:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
1862046:b900::/242046:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
1872046:ba00::/242046:baff:ffff:ffff:ffff:ffff:ffff:ffff
1882046:bb00::/242046:bbff:ffff:ffff:ffff:ffff:ffff:ffff
1892046:bc00::/242046:bcff:ffff:ffff:ffff:ffff:ffff:ffff
1902046:bd00::/242046:bdff:ffff:ffff:ffff:ffff:ffff:ffff
1912046:be00::/242046:beff:ffff:ffff:ffff:ffff:ffff:ffff
1922046:bf00::/242046:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1932046:c000::/242046:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
1942046:c100::/242046:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
1952046:c200::/242046:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
1962046:c300::/242046:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
1972046:c400::/242046:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
1982046:c500::/242046:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
1992046:c600::/242046:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
2002046:c700::/242046:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
2012046:c800::/242046:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
2022046:c900::/242046:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
2032046:ca00::/242046:caff:ffff:ffff:ffff:ffff:ffff:ffff
2042046:cb00::/242046:cbff:ffff:ffff:ffff:ffff:ffff:ffff
2052046:cc00::/242046:ccff:ffff:ffff:ffff:ffff:ffff:ffff
2062046:cd00::/242046:cdff:ffff:ffff:ffff:ffff:ffff:ffff
2072046:ce00::/242046:ceff:ffff:ffff:ffff:ffff:ffff:ffff
2082046:cf00::/242046:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2092046:d000::/242046:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
2102046:d100::/242046:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
2112046:d200::/242046:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
2122046:d300::/242046:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
2132046:d400::/242046:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
2142046:d500::/242046:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
2152046:d600::/242046:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
2162046:d700::/242046:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
2172046:d800::/242046:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
2182046:d900::/242046:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
2192046:da00::/242046:daff:ffff:ffff:ffff:ffff:ffff:ffff
2202046:db00::/242046:dbff:ffff:ffff:ffff:ffff:ffff:ffff
2212046:dc00::/242046:dcff:ffff:ffff:ffff:ffff:ffff:ffff
2222046:dd00::/242046:ddff:ffff:ffff:ffff:ffff:ffff:ffff
2232046:de00::/242046:deff:ffff:ffff:ffff:ffff:ffff:ffff
2242046:df00::/242046:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2252046:e000::/242046:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
2262046:e100::/242046:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
2272046:e200::/242046:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
2282046:e300::/242046:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
2292046:e400::/242046:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
2302046:e500::/242046:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
2312046:e600::/242046:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
2322046:e700::/242046:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
2332046:e800::/242046:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
2342046:e900::/242046:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
2352046:ea00::/242046:eaff:ffff:ffff:ffff:ffff:ffff:ffff
2362046:eb00::/242046:ebff:ffff:ffff:ffff:ffff:ffff:ffff
2372046:ec00::/242046:ecff:ffff:ffff:ffff:ffff:ffff:ffff
2382046:ed00::/242046:edff:ffff:ffff:ffff:ffff:ffff:ffff
2392046:ee00::/242046:eeff:ffff:ffff:ffff:ffff:ffff:ffff
2402046:ef00::/242046:efff:ffff:ffff:ffff:ffff:ffff:ffff
2412046:f000::/242046:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
2422046:f100::/242046:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
2432046:f200::/242046:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
2442046:f300::/242046:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
2452046:f400::/242046:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
2462046:f500::/242046:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
2472046:f600::/242046:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
2482046:f700::/242046:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
2492046:f800::/242046:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
2502046:f900::/242046:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
2512046:fa00::/242046:faff:ffff:ffff:ffff:ffff:ffff:ffff
2522046:fb00::/242046:fbff:ffff:ffff:ffff:ffff:ffff:ffff
2532046:fc00::/242046:fcff:ffff:ffff:ffff:ffff:ffff:ffff
2542046:fd00::/242046:fdff:ffff:ffff:ffff:ffff:ffff:ffff
2552046:fe00::/242046:feff:ffff:ffff:ffff:ffff:ffff:ffff
2562046:ff00::/242046: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.