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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
2050::/12
First address
2050::
Last address
205f: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
2050:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
5.0.2.ip6.arpa
Split into smaller subnets/24
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

2050::/12 makes 4,096 subnets of /24; the first 256 are listed.

Subnets
#SubnetLast address
12050::/242050:ff:ffff:ffff:ffff:ffff:ffff:ffff
22050:100::/242050:1ff:ffff:ffff:ffff:ffff:ffff:ffff
32050:200::/242050:2ff:ffff:ffff:ffff:ffff:ffff:ffff
42050:300::/242050:3ff:ffff:ffff:ffff:ffff:ffff:ffff
52050:400::/242050:4ff:ffff:ffff:ffff:ffff:ffff:ffff
62050:500::/242050:5ff:ffff:ffff:ffff:ffff:ffff:ffff
72050:600::/242050:6ff:ffff:ffff:ffff:ffff:ffff:ffff
82050:700::/242050:7ff:ffff:ffff:ffff:ffff:ffff:ffff
92050:800::/242050:8ff:ffff:ffff:ffff:ffff:ffff:ffff
102050:900::/242050:9ff:ffff:ffff:ffff:ffff:ffff:ffff
112050:a00::/242050:aff:ffff:ffff:ffff:ffff:ffff:ffff
122050:b00::/242050:bff:ffff:ffff:ffff:ffff:ffff:ffff
132050:c00::/242050:cff:ffff:ffff:ffff:ffff:ffff:ffff
142050:d00::/242050:dff:ffff:ffff:ffff:ffff:ffff:ffff
152050:e00::/242050:eff:ffff:ffff:ffff:ffff:ffff:ffff
162050:f00::/242050:fff:ffff:ffff:ffff:ffff:ffff:ffff
172050:1000::/242050:10ff:ffff:ffff:ffff:ffff:ffff:ffff
182050:1100::/242050:11ff:ffff:ffff:ffff:ffff:ffff:ffff
192050:1200::/242050:12ff:ffff:ffff:ffff:ffff:ffff:ffff
202050:1300::/242050:13ff:ffff:ffff:ffff:ffff:ffff:ffff
212050:1400::/242050:14ff:ffff:ffff:ffff:ffff:ffff:ffff
222050:1500::/242050:15ff:ffff:ffff:ffff:ffff:ffff:ffff
232050:1600::/242050:16ff:ffff:ffff:ffff:ffff:ffff:ffff
242050:1700::/242050:17ff:ffff:ffff:ffff:ffff:ffff:ffff
252050:1800::/242050:18ff:ffff:ffff:ffff:ffff:ffff:ffff
262050:1900::/242050:19ff:ffff:ffff:ffff:ffff:ffff:ffff
272050:1a00::/242050:1aff:ffff:ffff:ffff:ffff:ffff:ffff
282050:1b00::/242050:1bff:ffff:ffff:ffff:ffff:ffff:ffff
292050:1c00::/242050:1cff:ffff:ffff:ffff:ffff:ffff:ffff
302050:1d00::/242050:1dff:ffff:ffff:ffff:ffff:ffff:ffff
312050:1e00::/242050:1eff:ffff:ffff:ffff:ffff:ffff:ffff
322050:1f00::/242050:1fff:ffff:ffff:ffff:ffff:ffff:ffff
332050:2000::/242050:20ff:ffff:ffff:ffff:ffff:ffff:ffff
342050:2100::/242050:21ff:ffff:ffff:ffff:ffff:ffff:ffff
352050:2200::/242050:22ff:ffff:ffff:ffff:ffff:ffff:ffff
362050:2300::/242050:23ff:ffff:ffff:ffff:ffff:ffff:ffff
372050:2400::/242050:24ff:ffff:ffff:ffff:ffff:ffff:ffff
382050:2500::/242050:25ff:ffff:ffff:ffff:ffff:ffff:ffff
392050:2600::/242050:26ff:ffff:ffff:ffff:ffff:ffff:ffff
402050:2700::/242050:27ff:ffff:ffff:ffff:ffff:ffff:ffff
412050:2800::/242050:28ff:ffff:ffff:ffff:ffff:ffff:ffff
422050:2900::/242050:29ff:ffff:ffff:ffff:ffff:ffff:ffff
432050:2a00::/242050:2aff:ffff:ffff:ffff:ffff:ffff:ffff
442050:2b00::/242050:2bff:ffff:ffff:ffff:ffff:ffff:ffff
452050:2c00::/242050:2cff:ffff:ffff:ffff:ffff:ffff:ffff
462050:2d00::/242050:2dff:ffff:ffff:ffff:ffff:ffff:ffff
472050:2e00::/242050:2eff:ffff:ffff:ffff:ffff:ffff:ffff
482050:2f00::/242050:2fff:ffff:ffff:ffff:ffff:ffff:ffff
492050:3000::/242050:30ff:ffff:ffff:ffff:ffff:ffff:ffff
502050:3100::/242050:31ff:ffff:ffff:ffff:ffff:ffff:ffff
512050:3200::/242050:32ff:ffff:ffff:ffff:ffff:ffff:ffff
522050:3300::/242050:33ff:ffff:ffff:ffff:ffff:ffff:ffff
532050:3400::/242050:34ff:ffff:ffff:ffff:ffff:ffff:ffff
542050:3500::/242050:35ff:ffff:ffff:ffff:ffff:ffff:ffff
552050:3600::/242050:36ff:ffff:ffff:ffff:ffff:ffff:ffff
562050:3700::/242050:37ff:ffff:ffff:ffff:ffff:ffff:ffff
572050:3800::/242050:38ff:ffff:ffff:ffff:ffff:ffff:ffff
582050:3900::/242050:39ff:ffff:ffff:ffff:ffff:ffff:ffff
592050:3a00::/242050:3aff:ffff:ffff:ffff:ffff:ffff:ffff
602050:3b00::/242050:3bff:ffff:ffff:ffff:ffff:ffff:ffff
612050:3c00::/242050:3cff:ffff:ffff:ffff:ffff:ffff:ffff
622050:3d00::/242050:3dff:ffff:ffff:ffff:ffff:ffff:ffff
632050:3e00::/242050:3eff:ffff:ffff:ffff:ffff:ffff:ffff
642050:3f00::/242050:3fff:ffff:ffff:ffff:ffff:ffff:ffff
652050:4000::/242050:40ff:ffff:ffff:ffff:ffff:ffff:ffff
662050:4100::/242050:41ff:ffff:ffff:ffff:ffff:ffff:ffff
672050:4200::/242050:42ff:ffff:ffff:ffff:ffff:ffff:ffff
682050:4300::/242050:43ff:ffff:ffff:ffff:ffff:ffff:ffff
692050:4400::/242050:44ff:ffff:ffff:ffff:ffff:ffff:ffff
702050:4500::/242050:45ff:ffff:ffff:ffff:ffff:ffff:ffff
712050:4600::/242050:46ff:ffff:ffff:ffff:ffff:ffff:ffff
722050:4700::/242050:47ff:ffff:ffff:ffff:ffff:ffff:ffff
732050:4800::/242050:48ff:ffff:ffff:ffff:ffff:ffff:ffff
742050:4900::/242050:49ff:ffff:ffff:ffff:ffff:ffff:ffff
752050:4a00::/242050:4aff:ffff:ffff:ffff:ffff:ffff:ffff
762050:4b00::/242050:4bff:ffff:ffff:ffff:ffff:ffff:ffff
772050:4c00::/242050:4cff:ffff:ffff:ffff:ffff:ffff:ffff
782050:4d00::/242050:4dff:ffff:ffff:ffff:ffff:ffff:ffff
792050:4e00::/242050:4eff:ffff:ffff:ffff:ffff:ffff:ffff
802050:4f00::/242050:4fff:ffff:ffff:ffff:ffff:ffff:ffff
812050:5000::/242050:50ff:ffff:ffff:ffff:ffff:ffff:ffff
822050:5100::/242050:51ff:ffff:ffff:ffff:ffff:ffff:ffff
832050:5200::/242050:52ff:ffff:ffff:ffff:ffff:ffff:ffff
842050:5300::/242050:53ff:ffff:ffff:ffff:ffff:ffff:ffff
852050:5400::/242050:54ff:ffff:ffff:ffff:ffff:ffff:ffff
862050:5500::/242050:55ff:ffff:ffff:ffff:ffff:ffff:ffff
872050:5600::/242050:56ff:ffff:ffff:ffff:ffff:ffff:ffff
882050:5700::/242050:57ff:ffff:ffff:ffff:ffff:ffff:ffff
892050:5800::/242050:58ff:ffff:ffff:ffff:ffff:ffff:ffff
902050:5900::/242050:59ff:ffff:ffff:ffff:ffff:ffff:ffff
912050:5a00::/242050:5aff:ffff:ffff:ffff:ffff:ffff:ffff
922050:5b00::/242050:5bff:ffff:ffff:ffff:ffff:ffff:ffff
932050:5c00::/242050:5cff:ffff:ffff:ffff:ffff:ffff:ffff
942050:5d00::/242050:5dff:ffff:ffff:ffff:ffff:ffff:ffff
952050:5e00::/242050:5eff:ffff:ffff:ffff:ffff:ffff:ffff
962050:5f00::/242050:5fff:ffff:ffff:ffff:ffff:ffff:ffff
972050:6000::/242050:60ff:ffff:ffff:ffff:ffff:ffff:ffff
982050:6100::/242050:61ff:ffff:ffff:ffff:ffff:ffff:ffff
992050:6200::/242050:62ff:ffff:ffff:ffff:ffff:ffff:ffff
1002050:6300::/242050:63ff:ffff:ffff:ffff:ffff:ffff:ffff
1012050:6400::/242050:64ff:ffff:ffff:ffff:ffff:ffff:ffff
1022050:6500::/242050:65ff:ffff:ffff:ffff:ffff:ffff:ffff
1032050:6600::/242050:66ff:ffff:ffff:ffff:ffff:ffff:ffff
1042050:6700::/242050:67ff:ffff:ffff:ffff:ffff:ffff:ffff
1052050:6800::/242050:68ff:ffff:ffff:ffff:ffff:ffff:ffff
1062050:6900::/242050:69ff:ffff:ffff:ffff:ffff:ffff:ffff
1072050:6a00::/242050:6aff:ffff:ffff:ffff:ffff:ffff:ffff
1082050:6b00::/242050:6bff:ffff:ffff:ffff:ffff:ffff:ffff
1092050:6c00::/242050:6cff:ffff:ffff:ffff:ffff:ffff:ffff
1102050:6d00::/242050:6dff:ffff:ffff:ffff:ffff:ffff:ffff
1112050:6e00::/242050:6eff:ffff:ffff:ffff:ffff:ffff:ffff
1122050:6f00::/242050:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1132050:7000::/242050:70ff:ffff:ffff:ffff:ffff:ffff:ffff
1142050:7100::/242050:71ff:ffff:ffff:ffff:ffff:ffff:ffff
1152050:7200::/242050:72ff:ffff:ffff:ffff:ffff:ffff:ffff
1162050:7300::/242050:73ff:ffff:ffff:ffff:ffff:ffff:ffff
1172050:7400::/242050:74ff:ffff:ffff:ffff:ffff:ffff:ffff
1182050:7500::/242050:75ff:ffff:ffff:ffff:ffff:ffff:ffff
1192050:7600::/242050:76ff:ffff:ffff:ffff:ffff:ffff:ffff
1202050:7700::/242050:77ff:ffff:ffff:ffff:ffff:ffff:ffff
1212050:7800::/242050:78ff:ffff:ffff:ffff:ffff:ffff:ffff
1222050:7900::/242050:79ff:ffff:ffff:ffff:ffff:ffff:ffff
1232050:7a00::/242050:7aff:ffff:ffff:ffff:ffff:ffff:ffff
1242050:7b00::/242050:7bff:ffff:ffff:ffff:ffff:ffff:ffff
1252050:7c00::/242050:7cff:ffff:ffff:ffff:ffff:ffff:ffff
1262050:7d00::/242050:7dff:ffff:ffff:ffff:ffff:ffff:ffff
1272050:7e00::/242050:7eff:ffff:ffff:ffff:ffff:ffff:ffff
1282050:7f00::/242050:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1292050:8000::/242050:80ff:ffff:ffff:ffff:ffff:ffff:ffff
1302050:8100::/242050:81ff:ffff:ffff:ffff:ffff:ffff:ffff
1312050:8200::/242050:82ff:ffff:ffff:ffff:ffff:ffff:ffff
1322050:8300::/242050:83ff:ffff:ffff:ffff:ffff:ffff:ffff
1332050:8400::/242050:84ff:ffff:ffff:ffff:ffff:ffff:ffff
1342050:8500::/242050:85ff:ffff:ffff:ffff:ffff:ffff:ffff
1352050:8600::/242050:86ff:ffff:ffff:ffff:ffff:ffff:ffff
1362050:8700::/242050:87ff:ffff:ffff:ffff:ffff:ffff:ffff
1372050:8800::/242050:88ff:ffff:ffff:ffff:ffff:ffff:ffff
1382050:8900::/242050:89ff:ffff:ffff:ffff:ffff:ffff:ffff
1392050:8a00::/242050:8aff:ffff:ffff:ffff:ffff:ffff:ffff
1402050:8b00::/242050:8bff:ffff:ffff:ffff:ffff:ffff:ffff
1412050:8c00::/242050:8cff:ffff:ffff:ffff:ffff:ffff:ffff
1422050:8d00::/242050:8dff:ffff:ffff:ffff:ffff:ffff:ffff
1432050:8e00::/242050:8eff:ffff:ffff:ffff:ffff:ffff:ffff
1442050:8f00::/242050:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1452050:9000::/242050:90ff:ffff:ffff:ffff:ffff:ffff:ffff
1462050:9100::/242050:91ff:ffff:ffff:ffff:ffff:ffff:ffff
1472050:9200::/242050:92ff:ffff:ffff:ffff:ffff:ffff:ffff
1482050:9300::/242050:93ff:ffff:ffff:ffff:ffff:ffff:ffff
1492050:9400::/242050:94ff:ffff:ffff:ffff:ffff:ffff:ffff
1502050:9500::/242050:95ff:ffff:ffff:ffff:ffff:ffff:ffff
1512050:9600::/242050:96ff:ffff:ffff:ffff:ffff:ffff:ffff
1522050:9700::/242050:97ff:ffff:ffff:ffff:ffff:ffff:ffff
1532050:9800::/242050:98ff:ffff:ffff:ffff:ffff:ffff:ffff
1542050:9900::/242050:99ff:ffff:ffff:ffff:ffff:ffff:ffff
1552050:9a00::/242050:9aff:ffff:ffff:ffff:ffff:ffff:ffff
1562050:9b00::/242050:9bff:ffff:ffff:ffff:ffff:ffff:ffff
1572050:9c00::/242050:9cff:ffff:ffff:ffff:ffff:ffff:ffff
1582050:9d00::/242050:9dff:ffff:ffff:ffff:ffff:ffff:ffff
1592050:9e00::/242050:9eff:ffff:ffff:ffff:ffff:ffff:ffff
1602050:9f00::/242050:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1612050:a000::/242050:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
1622050:a100::/242050:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
1632050:a200::/242050:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
1642050:a300::/242050:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
1652050:a400::/242050:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
1662050:a500::/242050:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
1672050:a600::/242050:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
1682050:a700::/242050:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
1692050:a800::/242050:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
1702050:a900::/242050:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
1712050:aa00::/242050:aaff:ffff:ffff:ffff:ffff:ffff:ffff
1722050:ab00::/242050:abff:ffff:ffff:ffff:ffff:ffff:ffff
1732050:ac00::/242050:acff:ffff:ffff:ffff:ffff:ffff:ffff
1742050:ad00::/242050:adff:ffff:ffff:ffff:ffff:ffff:ffff
1752050:ae00::/242050:aeff:ffff:ffff:ffff:ffff:ffff:ffff
1762050:af00::/242050:afff:ffff:ffff:ffff:ffff:ffff:ffff
1772050:b000::/242050:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
1782050:b100::/242050:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
1792050:b200::/242050:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
1802050:b300::/242050:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
1812050:b400::/242050:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
1822050:b500::/242050:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
1832050:b600::/242050:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
1842050:b700::/242050:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
1852050:b800::/242050:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
1862050:b900::/242050:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
1872050:ba00::/242050:baff:ffff:ffff:ffff:ffff:ffff:ffff
1882050:bb00::/242050:bbff:ffff:ffff:ffff:ffff:ffff:ffff
1892050:bc00::/242050:bcff:ffff:ffff:ffff:ffff:ffff:ffff
1902050:bd00::/242050:bdff:ffff:ffff:ffff:ffff:ffff:ffff
1912050:be00::/242050:beff:ffff:ffff:ffff:ffff:ffff:ffff
1922050:bf00::/242050:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1932050:c000::/242050:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
1942050:c100::/242050:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
1952050:c200::/242050:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
1962050:c300::/242050:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
1972050:c400::/242050:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
1982050:c500::/242050:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
1992050:c600::/242050:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
2002050:c700::/242050:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
2012050:c800::/242050:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
2022050:c900::/242050:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
2032050:ca00::/242050:caff:ffff:ffff:ffff:ffff:ffff:ffff
2042050:cb00::/242050:cbff:ffff:ffff:ffff:ffff:ffff:ffff
2052050:cc00::/242050:ccff:ffff:ffff:ffff:ffff:ffff:ffff
2062050:cd00::/242050:cdff:ffff:ffff:ffff:ffff:ffff:ffff
2072050:ce00::/242050:ceff:ffff:ffff:ffff:ffff:ffff:ffff
2082050:cf00::/242050:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2092050:d000::/242050:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
2102050:d100::/242050:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
2112050:d200::/242050:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
2122050:d300::/242050:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
2132050:d400::/242050:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
2142050:d500::/242050:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
2152050:d600::/242050:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
2162050:d700::/242050:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
2172050:d800::/242050:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
2182050:d900::/242050:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
2192050:da00::/242050:daff:ffff:ffff:ffff:ffff:ffff:ffff
2202050:db00::/242050:dbff:ffff:ffff:ffff:ffff:ffff:ffff
2212050:dc00::/242050:dcff:ffff:ffff:ffff:ffff:ffff:ffff
2222050:dd00::/242050:ddff:ffff:ffff:ffff:ffff:ffff:ffff
2232050:de00::/242050:deff:ffff:ffff:ffff:ffff:ffff:ffff
2242050:df00::/242050:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2252050:e000::/242050:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
2262050:e100::/242050:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
2272050:e200::/242050:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
2282050:e300::/242050:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
2292050:e400::/242050:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
2302050:e500::/242050:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
2312050:e600::/242050:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
2322050:e700::/242050:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
2332050:e800::/242050:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
2342050:e900::/242050:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
2352050:ea00::/242050:eaff:ffff:ffff:ffff:ffff:ffff:ffff
2362050:eb00::/242050:ebff:ffff:ffff:ffff:ffff:ffff:ffff
2372050:ec00::/242050:ecff:ffff:ffff:ffff:ffff:ffff:ffff
2382050:ed00::/242050:edff:ffff:ffff:ffff:ffff:ffff:ffff
2392050:ee00::/242050:eeff:ffff:ffff:ffff:ffff:ffff:ffff
2402050:ef00::/242050:efff:ffff:ffff:ffff:ffff:ffff:ffff
2412050:f000::/242050:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
2422050:f100::/242050:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
2432050:f200::/242050:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
2442050:f300::/242050:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
2452050:f400::/242050:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
2462050:f500::/242050:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
2472050:f600::/242050:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
2482050:f700::/242050:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
2492050:f800::/242050:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
2502050:f900::/242050:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
2512050:fa00::/242050:faff:ffff:ffff:ffff:ffff:ffff:ffff
2522050:fb00::/242050:fbff:ffff:ffff:ffff:ffff:ffff:ffff
2532050:fc00::/242050:fcff:ffff:ffff:ffff:ffff:ffff:ffff
2542050:fd00::/242050:fdff:ffff:ffff:ffff:ffff:ffff:ffff
2552050:fe00::/242050:feff:ffff:ffff:ffff:ffff:ffff:ffff
2562050:ff00::/242050: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.