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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
2350::/12
First address
2350::
Last address
235f: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
2350:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
5.3.2.ip6.arpa
Split into smaller subnets/24
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

2350::/12 makes 4,096 subnets of /24; the first 256 are listed.

Subnets
#SubnetLast address
12350::/242350:ff:ffff:ffff:ffff:ffff:ffff:ffff
22350:100::/242350:1ff:ffff:ffff:ffff:ffff:ffff:ffff
32350:200::/242350:2ff:ffff:ffff:ffff:ffff:ffff:ffff
42350:300::/242350:3ff:ffff:ffff:ffff:ffff:ffff:ffff
52350:400::/242350:4ff:ffff:ffff:ffff:ffff:ffff:ffff
62350:500::/242350:5ff:ffff:ffff:ffff:ffff:ffff:ffff
72350:600::/242350:6ff:ffff:ffff:ffff:ffff:ffff:ffff
82350:700::/242350:7ff:ffff:ffff:ffff:ffff:ffff:ffff
92350:800::/242350:8ff:ffff:ffff:ffff:ffff:ffff:ffff
102350:900::/242350:9ff:ffff:ffff:ffff:ffff:ffff:ffff
112350:a00::/242350:aff:ffff:ffff:ffff:ffff:ffff:ffff
122350:b00::/242350:bff:ffff:ffff:ffff:ffff:ffff:ffff
132350:c00::/242350:cff:ffff:ffff:ffff:ffff:ffff:ffff
142350:d00::/242350:dff:ffff:ffff:ffff:ffff:ffff:ffff
152350:e00::/242350:eff:ffff:ffff:ffff:ffff:ffff:ffff
162350:f00::/242350:fff:ffff:ffff:ffff:ffff:ffff:ffff
172350:1000::/242350:10ff:ffff:ffff:ffff:ffff:ffff:ffff
182350:1100::/242350:11ff:ffff:ffff:ffff:ffff:ffff:ffff
192350:1200::/242350:12ff:ffff:ffff:ffff:ffff:ffff:ffff
202350:1300::/242350:13ff:ffff:ffff:ffff:ffff:ffff:ffff
212350:1400::/242350:14ff:ffff:ffff:ffff:ffff:ffff:ffff
222350:1500::/242350:15ff:ffff:ffff:ffff:ffff:ffff:ffff
232350:1600::/242350:16ff:ffff:ffff:ffff:ffff:ffff:ffff
242350:1700::/242350:17ff:ffff:ffff:ffff:ffff:ffff:ffff
252350:1800::/242350:18ff:ffff:ffff:ffff:ffff:ffff:ffff
262350:1900::/242350:19ff:ffff:ffff:ffff:ffff:ffff:ffff
272350:1a00::/242350:1aff:ffff:ffff:ffff:ffff:ffff:ffff
282350:1b00::/242350:1bff:ffff:ffff:ffff:ffff:ffff:ffff
292350:1c00::/242350:1cff:ffff:ffff:ffff:ffff:ffff:ffff
302350:1d00::/242350:1dff:ffff:ffff:ffff:ffff:ffff:ffff
312350:1e00::/242350:1eff:ffff:ffff:ffff:ffff:ffff:ffff
322350:1f00::/242350:1fff:ffff:ffff:ffff:ffff:ffff:ffff
332350:2000::/242350:20ff:ffff:ffff:ffff:ffff:ffff:ffff
342350:2100::/242350:21ff:ffff:ffff:ffff:ffff:ffff:ffff
352350:2200::/242350:22ff:ffff:ffff:ffff:ffff:ffff:ffff
362350:2300::/242350:23ff:ffff:ffff:ffff:ffff:ffff:ffff
372350:2400::/242350:24ff:ffff:ffff:ffff:ffff:ffff:ffff
382350:2500::/242350:25ff:ffff:ffff:ffff:ffff:ffff:ffff
392350:2600::/242350:26ff:ffff:ffff:ffff:ffff:ffff:ffff
402350:2700::/242350:27ff:ffff:ffff:ffff:ffff:ffff:ffff
412350:2800::/242350:28ff:ffff:ffff:ffff:ffff:ffff:ffff
422350:2900::/242350:29ff:ffff:ffff:ffff:ffff:ffff:ffff
432350:2a00::/242350:2aff:ffff:ffff:ffff:ffff:ffff:ffff
442350:2b00::/242350:2bff:ffff:ffff:ffff:ffff:ffff:ffff
452350:2c00::/242350:2cff:ffff:ffff:ffff:ffff:ffff:ffff
462350:2d00::/242350:2dff:ffff:ffff:ffff:ffff:ffff:ffff
472350:2e00::/242350:2eff:ffff:ffff:ffff:ffff:ffff:ffff
482350:2f00::/242350:2fff:ffff:ffff:ffff:ffff:ffff:ffff
492350:3000::/242350:30ff:ffff:ffff:ffff:ffff:ffff:ffff
502350:3100::/242350:31ff:ffff:ffff:ffff:ffff:ffff:ffff
512350:3200::/242350:32ff:ffff:ffff:ffff:ffff:ffff:ffff
522350:3300::/242350:33ff:ffff:ffff:ffff:ffff:ffff:ffff
532350:3400::/242350:34ff:ffff:ffff:ffff:ffff:ffff:ffff
542350:3500::/242350:35ff:ffff:ffff:ffff:ffff:ffff:ffff
552350:3600::/242350:36ff:ffff:ffff:ffff:ffff:ffff:ffff
562350:3700::/242350:37ff:ffff:ffff:ffff:ffff:ffff:ffff
572350:3800::/242350:38ff:ffff:ffff:ffff:ffff:ffff:ffff
582350:3900::/242350:39ff:ffff:ffff:ffff:ffff:ffff:ffff
592350:3a00::/242350:3aff:ffff:ffff:ffff:ffff:ffff:ffff
602350:3b00::/242350:3bff:ffff:ffff:ffff:ffff:ffff:ffff
612350:3c00::/242350:3cff:ffff:ffff:ffff:ffff:ffff:ffff
622350:3d00::/242350:3dff:ffff:ffff:ffff:ffff:ffff:ffff
632350:3e00::/242350:3eff:ffff:ffff:ffff:ffff:ffff:ffff
642350:3f00::/242350:3fff:ffff:ffff:ffff:ffff:ffff:ffff
652350:4000::/242350:40ff:ffff:ffff:ffff:ffff:ffff:ffff
662350:4100::/242350:41ff:ffff:ffff:ffff:ffff:ffff:ffff
672350:4200::/242350:42ff:ffff:ffff:ffff:ffff:ffff:ffff
682350:4300::/242350:43ff:ffff:ffff:ffff:ffff:ffff:ffff
692350:4400::/242350:44ff:ffff:ffff:ffff:ffff:ffff:ffff
702350:4500::/242350:45ff:ffff:ffff:ffff:ffff:ffff:ffff
712350:4600::/242350:46ff:ffff:ffff:ffff:ffff:ffff:ffff
722350:4700::/242350:47ff:ffff:ffff:ffff:ffff:ffff:ffff
732350:4800::/242350:48ff:ffff:ffff:ffff:ffff:ffff:ffff
742350:4900::/242350:49ff:ffff:ffff:ffff:ffff:ffff:ffff
752350:4a00::/242350:4aff:ffff:ffff:ffff:ffff:ffff:ffff
762350:4b00::/242350:4bff:ffff:ffff:ffff:ffff:ffff:ffff
772350:4c00::/242350:4cff:ffff:ffff:ffff:ffff:ffff:ffff
782350:4d00::/242350:4dff:ffff:ffff:ffff:ffff:ffff:ffff
792350:4e00::/242350:4eff:ffff:ffff:ffff:ffff:ffff:ffff
802350:4f00::/242350:4fff:ffff:ffff:ffff:ffff:ffff:ffff
812350:5000::/242350:50ff:ffff:ffff:ffff:ffff:ffff:ffff
822350:5100::/242350:51ff:ffff:ffff:ffff:ffff:ffff:ffff
832350:5200::/242350:52ff:ffff:ffff:ffff:ffff:ffff:ffff
842350:5300::/242350:53ff:ffff:ffff:ffff:ffff:ffff:ffff
852350:5400::/242350:54ff:ffff:ffff:ffff:ffff:ffff:ffff
862350:5500::/242350:55ff:ffff:ffff:ffff:ffff:ffff:ffff
872350:5600::/242350:56ff:ffff:ffff:ffff:ffff:ffff:ffff
882350:5700::/242350:57ff:ffff:ffff:ffff:ffff:ffff:ffff
892350:5800::/242350:58ff:ffff:ffff:ffff:ffff:ffff:ffff
902350:5900::/242350:59ff:ffff:ffff:ffff:ffff:ffff:ffff
912350:5a00::/242350:5aff:ffff:ffff:ffff:ffff:ffff:ffff
922350:5b00::/242350:5bff:ffff:ffff:ffff:ffff:ffff:ffff
932350:5c00::/242350:5cff:ffff:ffff:ffff:ffff:ffff:ffff
942350:5d00::/242350:5dff:ffff:ffff:ffff:ffff:ffff:ffff
952350:5e00::/242350:5eff:ffff:ffff:ffff:ffff:ffff:ffff
962350:5f00::/242350:5fff:ffff:ffff:ffff:ffff:ffff:ffff
972350:6000::/242350:60ff:ffff:ffff:ffff:ffff:ffff:ffff
982350:6100::/242350:61ff:ffff:ffff:ffff:ffff:ffff:ffff
992350:6200::/242350:62ff:ffff:ffff:ffff:ffff:ffff:ffff
1002350:6300::/242350:63ff:ffff:ffff:ffff:ffff:ffff:ffff
1012350:6400::/242350:64ff:ffff:ffff:ffff:ffff:ffff:ffff
1022350:6500::/242350:65ff:ffff:ffff:ffff:ffff:ffff:ffff
1032350:6600::/242350:66ff:ffff:ffff:ffff:ffff:ffff:ffff
1042350:6700::/242350:67ff:ffff:ffff:ffff:ffff:ffff:ffff
1052350:6800::/242350:68ff:ffff:ffff:ffff:ffff:ffff:ffff
1062350:6900::/242350:69ff:ffff:ffff:ffff:ffff:ffff:ffff
1072350:6a00::/242350:6aff:ffff:ffff:ffff:ffff:ffff:ffff
1082350:6b00::/242350:6bff:ffff:ffff:ffff:ffff:ffff:ffff
1092350:6c00::/242350:6cff:ffff:ffff:ffff:ffff:ffff:ffff
1102350:6d00::/242350:6dff:ffff:ffff:ffff:ffff:ffff:ffff
1112350:6e00::/242350:6eff:ffff:ffff:ffff:ffff:ffff:ffff
1122350:6f00::/242350:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1132350:7000::/242350:70ff:ffff:ffff:ffff:ffff:ffff:ffff
1142350:7100::/242350:71ff:ffff:ffff:ffff:ffff:ffff:ffff
1152350:7200::/242350:72ff:ffff:ffff:ffff:ffff:ffff:ffff
1162350:7300::/242350:73ff:ffff:ffff:ffff:ffff:ffff:ffff
1172350:7400::/242350:74ff:ffff:ffff:ffff:ffff:ffff:ffff
1182350:7500::/242350:75ff:ffff:ffff:ffff:ffff:ffff:ffff
1192350:7600::/242350:76ff:ffff:ffff:ffff:ffff:ffff:ffff
1202350:7700::/242350:77ff:ffff:ffff:ffff:ffff:ffff:ffff
1212350:7800::/242350:78ff:ffff:ffff:ffff:ffff:ffff:ffff
1222350:7900::/242350:79ff:ffff:ffff:ffff:ffff:ffff:ffff
1232350:7a00::/242350:7aff:ffff:ffff:ffff:ffff:ffff:ffff
1242350:7b00::/242350:7bff:ffff:ffff:ffff:ffff:ffff:ffff
1252350:7c00::/242350:7cff:ffff:ffff:ffff:ffff:ffff:ffff
1262350:7d00::/242350:7dff:ffff:ffff:ffff:ffff:ffff:ffff
1272350:7e00::/242350:7eff:ffff:ffff:ffff:ffff:ffff:ffff
1282350:7f00::/242350:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1292350:8000::/242350:80ff:ffff:ffff:ffff:ffff:ffff:ffff
1302350:8100::/242350:81ff:ffff:ffff:ffff:ffff:ffff:ffff
1312350:8200::/242350:82ff:ffff:ffff:ffff:ffff:ffff:ffff
1322350:8300::/242350:83ff:ffff:ffff:ffff:ffff:ffff:ffff
1332350:8400::/242350:84ff:ffff:ffff:ffff:ffff:ffff:ffff
1342350:8500::/242350:85ff:ffff:ffff:ffff:ffff:ffff:ffff
1352350:8600::/242350:86ff:ffff:ffff:ffff:ffff:ffff:ffff
1362350:8700::/242350:87ff:ffff:ffff:ffff:ffff:ffff:ffff
1372350:8800::/242350:88ff:ffff:ffff:ffff:ffff:ffff:ffff
1382350:8900::/242350:89ff:ffff:ffff:ffff:ffff:ffff:ffff
1392350:8a00::/242350:8aff:ffff:ffff:ffff:ffff:ffff:ffff
1402350:8b00::/242350:8bff:ffff:ffff:ffff:ffff:ffff:ffff
1412350:8c00::/242350:8cff:ffff:ffff:ffff:ffff:ffff:ffff
1422350:8d00::/242350:8dff:ffff:ffff:ffff:ffff:ffff:ffff
1432350:8e00::/242350:8eff:ffff:ffff:ffff:ffff:ffff:ffff
1442350:8f00::/242350:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1452350:9000::/242350:90ff:ffff:ffff:ffff:ffff:ffff:ffff
1462350:9100::/242350:91ff:ffff:ffff:ffff:ffff:ffff:ffff
1472350:9200::/242350:92ff:ffff:ffff:ffff:ffff:ffff:ffff
1482350:9300::/242350:93ff:ffff:ffff:ffff:ffff:ffff:ffff
1492350:9400::/242350:94ff:ffff:ffff:ffff:ffff:ffff:ffff
1502350:9500::/242350:95ff:ffff:ffff:ffff:ffff:ffff:ffff
1512350:9600::/242350:96ff:ffff:ffff:ffff:ffff:ffff:ffff
1522350:9700::/242350:97ff:ffff:ffff:ffff:ffff:ffff:ffff
1532350:9800::/242350:98ff:ffff:ffff:ffff:ffff:ffff:ffff
1542350:9900::/242350:99ff:ffff:ffff:ffff:ffff:ffff:ffff
1552350:9a00::/242350:9aff:ffff:ffff:ffff:ffff:ffff:ffff
1562350:9b00::/242350:9bff:ffff:ffff:ffff:ffff:ffff:ffff
1572350:9c00::/242350:9cff:ffff:ffff:ffff:ffff:ffff:ffff
1582350:9d00::/242350:9dff:ffff:ffff:ffff:ffff:ffff:ffff
1592350:9e00::/242350:9eff:ffff:ffff:ffff:ffff:ffff:ffff
1602350:9f00::/242350:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1612350:a000::/242350:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
1622350:a100::/242350:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
1632350:a200::/242350:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
1642350:a300::/242350:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
1652350:a400::/242350:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
1662350:a500::/242350:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
1672350:a600::/242350:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
1682350:a700::/242350:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
1692350:a800::/242350:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
1702350:a900::/242350:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
1712350:aa00::/242350:aaff:ffff:ffff:ffff:ffff:ffff:ffff
1722350:ab00::/242350:abff:ffff:ffff:ffff:ffff:ffff:ffff
1732350:ac00::/242350:acff:ffff:ffff:ffff:ffff:ffff:ffff
1742350:ad00::/242350:adff:ffff:ffff:ffff:ffff:ffff:ffff
1752350:ae00::/242350:aeff:ffff:ffff:ffff:ffff:ffff:ffff
1762350:af00::/242350:afff:ffff:ffff:ffff:ffff:ffff:ffff
1772350:b000::/242350:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
1782350:b100::/242350:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
1792350:b200::/242350:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
1802350:b300::/242350:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
1812350:b400::/242350:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
1822350:b500::/242350:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
1832350:b600::/242350:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
1842350:b700::/242350:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
1852350:b800::/242350:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
1862350:b900::/242350:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
1872350:ba00::/242350:baff:ffff:ffff:ffff:ffff:ffff:ffff
1882350:bb00::/242350:bbff:ffff:ffff:ffff:ffff:ffff:ffff
1892350:bc00::/242350:bcff:ffff:ffff:ffff:ffff:ffff:ffff
1902350:bd00::/242350:bdff:ffff:ffff:ffff:ffff:ffff:ffff
1912350:be00::/242350:beff:ffff:ffff:ffff:ffff:ffff:ffff
1922350:bf00::/242350:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1932350:c000::/242350:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
1942350:c100::/242350:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
1952350:c200::/242350:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
1962350:c300::/242350:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
1972350:c400::/242350:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
1982350:c500::/242350:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
1992350:c600::/242350:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
2002350:c700::/242350:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
2012350:c800::/242350:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
2022350:c900::/242350:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
2032350:ca00::/242350:caff:ffff:ffff:ffff:ffff:ffff:ffff
2042350:cb00::/242350:cbff:ffff:ffff:ffff:ffff:ffff:ffff
2052350:cc00::/242350:ccff:ffff:ffff:ffff:ffff:ffff:ffff
2062350:cd00::/242350:cdff:ffff:ffff:ffff:ffff:ffff:ffff
2072350:ce00::/242350:ceff:ffff:ffff:ffff:ffff:ffff:ffff
2082350:cf00::/242350:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2092350:d000::/242350:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
2102350:d100::/242350:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
2112350:d200::/242350:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
2122350:d300::/242350:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
2132350:d400::/242350:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
2142350:d500::/242350:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
2152350:d600::/242350:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
2162350:d700::/242350:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
2172350:d800::/242350:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
2182350:d900::/242350:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
2192350:da00::/242350:daff:ffff:ffff:ffff:ffff:ffff:ffff
2202350:db00::/242350:dbff:ffff:ffff:ffff:ffff:ffff:ffff
2212350:dc00::/242350:dcff:ffff:ffff:ffff:ffff:ffff:ffff
2222350:dd00::/242350:ddff:ffff:ffff:ffff:ffff:ffff:ffff
2232350:de00::/242350:deff:ffff:ffff:ffff:ffff:ffff:ffff
2242350:df00::/242350:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2252350:e000::/242350:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
2262350:e100::/242350:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
2272350:e200::/242350:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
2282350:e300::/242350:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
2292350:e400::/242350:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
2302350:e500::/242350:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
2312350:e600::/242350:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
2322350:e700::/242350:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
2332350:e800::/242350:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
2342350:e900::/242350:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
2352350:ea00::/242350:eaff:ffff:ffff:ffff:ffff:ffff:ffff
2362350:eb00::/242350:ebff:ffff:ffff:ffff:ffff:ffff:ffff
2372350:ec00::/242350:ecff:ffff:ffff:ffff:ffff:ffff:ffff
2382350:ed00::/242350:edff:ffff:ffff:ffff:ffff:ffff:ffff
2392350:ee00::/242350:eeff:ffff:ffff:ffff:ffff:ffff:ffff
2402350:ef00::/242350:efff:ffff:ffff:ffff:ffff:ffff:ffff
2412350:f000::/242350:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
2422350:f100::/242350:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
2432350:f200::/242350:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
2442350:f300::/242350:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
2452350:f400::/242350:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
2462350:f500::/242350:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
2472350:f600::/242350:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
2482350:f700::/242350:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
2492350:f800::/242350:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
2502350:f900::/242350:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
2512350:fa00::/242350:faff:ffff:ffff:ffff:ffff:ffff:ffff
2522350:fb00::/242350:fbff:ffff:ffff:ffff:ffff:ffff:ffff
2532350:fc00::/242350:fcff:ffff:ffff:ffff:ffff:ffff:ffff
2542350:fd00::/242350:fdff:ffff:ffff:ffff:ffff:ffff:ffff
2552350:fe00::/242350:feff:ffff:ffff:ffff:ffff:ffff:ffff
2562350:ff00::/242350: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.