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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
2730::/12
First address
2730::
Last address
273f: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
2730:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
3.7.2.ip6.arpa
Split into smaller subnets/24
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

2730::/12 makes 4,096 subnets of /24; the first 256 are listed.

Subnets
#SubnetLast address
12730::/242730:ff:ffff:ffff:ffff:ffff:ffff:ffff
22730:100::/242730:1ff:ffff:ffff:ffff:ffff:ffff:ffff
32730:200::/242730:2ff:ffff:ffff:ffff:ffff:ffff:ffff
42730:300::/242730:3ff:ffff:ffff:ffff:ffff:ffff:ffff
52730:400::/242730:4ff:ffff:ffff:ffff:ffff:ffff:ffff
62730:500::/242730:5ff:ffff:ffff:ffff:ffff:ffff:ffff
72730:600::/242730:6ff:ffff:ffff:ffff:ffff:ffff:ffff
82730:700::/242730:7ff:ffff:ffff:ffff:ffff:ffff:ffff
92730:800::/242730:8ff:ffff:ffff:ffff:ffff:ffff:ffff
102730:900::/242730:9ff:ffff:ffff:ffff:ffff:ffff:ffff
112730:a00::/242730:aff:ffff:ffff:ffff:ffff:ffff:ffff
122730:b00::/242730:bff:ffff:ffff:ffff:ffff:ffff:ffff
132730:c00::/242730:cff:ffff:ffff:ffff:ffff:ffff:ffff
142730:d00::/242730:dff:ffff:ffff:ffff:ffff:ffff:ffff
152730:e00::/242730:eff:ffff:ffff:ffff:ffff:ffff:ffff
162730:f00::/242730:fff:ffff:ffff:ffff:ffff:ffff:ffff
172730:1000::/242730:10ff:ffff:ffff:ffff:ffff:ffff:ffff
182730:1100::/242730:11ff:ffff:ffff:ffff:ffff:ffff:ffff
192730:1200::/242730:12ff:ffff:ffff:ffff:ffff:ffff:ffff
202730:1300::/242730:13ff:ffff:ffff:ffff:ffff:ffff:ffff
212730:1400::/242730:14ff:ffff:ffff:ffff:ffff:ffff:ffff
222730:1500::/242730:15ff:ffff:ffff:ffff:ffff:ffff:ffff
232730:1600::/242730:16ff:ffff:ffff:ffff:ffff:ffff:ffff
242730:1700::/242730:17ff:ffff:ffff:ffff:ffff:ffff:ffff
252730:1800::/242730:18ff:ffff:ffff:ffff:ffff:ffff:ffff
262730:1900::/242730:19ff:ffff:ffff:ffff:ffff:ffff:ffff
272730:1a00::/242730:1aff:ffff:ffff:ffff:ffff:ffff:ffff
282730:1b00::/242730:1bff:ffff:ffff:ffff:ffff:ffff:ffff
292730:1c00::/242730:1cff:ffff:ffff:ffff:ffff:ffff:ffff
302730:1d00::/242730:1dff:ffff:ffff:ffff:ffff:ffff:ffff
312730:1e00::/242730:1eff:ffff:ffff:ffff:ffff:ffff:ffff
322730:1f00::/242730:1fff:ffff:ffff:ffff:ffff:ffff:ffff
332730:2000::/242730:20ff:ffff:ffff:ffff:ffff:ffff:ffff
342730:2100::/242730:21ff:ffff:ffff:ffff:ffff:ffff:ffff
352730:2200::/242730:22ff:ffff:ffff:ffff:ffff:ffff:ffff
362730:2300::/242730:23ff:ffff:ffff:ffff:ffff:ffff:ffff
372730:2400::/242730:24ff:ffff:ffff:ffff:ffff:ffff:ffff
382730:2500::/242730:25ff:ffff:ffff:ffff:ffff:ffff:ffff
392730:2600::/242730:26ff:ffff:ffff:ffff:ffff:ffff:ffff
402730:2700::/242730:27ff:ffff:ffff:ffff:ffff:ffff:ffff
412730:2800::/242730:28ff:ffff:ffff:ffff:ffff:ffff:ffff
422730:2900::/242730:29ff:ffff:ffff:ffff:ffff:ffff:ffff
432730:2a00::/242730:2aff:ffff:ffff:ffff:ffff:ffff:ffff
442730:2b00::/242730:2bff:ffff:ffff:ffff:ffff:ffff:ffff
452730:2c00::/242730:2cff:ffff:ffff:ffff:ffff:ffff:ffff
462730:2d00::/242730:2dff:ffff:ffff:ffff:ffff:ffff:ffff
472730:2e00::/242730:2eff:ffff:ffff:ffff:ffff:ffff:ffff
482730:2f00::/242730:2fff:ffff:ffff:ffff:ffff:ffff:ffff
492730:3000::/242730:30ff:ffff:ffff:ffff:ffff:ffff:ffff
502730:3100::/242730:31ff:ffff:ffff:ffff:ffff:ffff:ffff
512730:3200::/242730:32ff:ffff:ffff:ffff:ffff:ffff:ffff
522730:3300::/242730:33ff:ffff:ffff:ffff:ffff:ffff:ffff
532730:3400::/242730:34ff:ffff:ffff:ffff:ffff:ffff:ffff
542730:3500::/242730:35ff:ffff:ffff:ffff:ffff:ffff:ffff
552730:3600::/242730:36ff:ffff:ffff:ffff:ffff:ffff:ffff
562730:3700::/242730:37ff:ffff:ffff:ffff:ffff:ffff:ffff
572730:3800::/242730:38ff:ffff:ffff:ffff:ffff:ffff:ffff
582730:3900::/242730:39ff:ffff:ffff:ffff:ffff:ffff:ffff
592730:3a00::/242730:3aff:ffff:ffff:ffff:ffff:ffff:ffff
602730:3b00::/242730:3bff:ffff:ffff:ffff:ffff:ffff:ffff
612730:3c00::/242730:3cff:ffff:ffff:ffff:ffff:ffff:ffff
622730:3d00::/242730:3dff:ffff:ffff:ffff:ffff:ffff:ffff
632730:3e00::/242730:3eff:ffff:ffff:ffff:ffff:ffff:ffff
642730:3f00::/242730:3fff:ffff:ffff:ffff:ffff:ffff:ffff
652730:4000::/242730:40ff:ffff:ffff:ffff:ffff:ffff:ffff
662730:4100::/242730:41ff:ffff:ffff:ffff:ffff:ffff:ffff
672730:4200::/242730:42ff:ffff:ffff:ffff:ffff:ffff:ffff
682730:4300::/242730:43ff:ffff:ffff:ffff:ffff:ffff:ffff
692730:4400::/242730:44ff:ffff:ffff:ffff:ffff:ffff:ffff
702730:4500::/242730:45ff:ffff:ffff:ffff:ffff:ffff:ffff
712730:4600::/242730:46ff:ffff:ffff:ffff:ffff:ffff:ffff
722730:4700::/242730:47ff:ffff:ffff:ffff:ffff:ffff:ffff
732730:4800::/242730:48ff:ffff:ffff:ffff:ffff:ffff:ffff
742730:4900::/242730:49ff:ffff:ffff:ffff:ffff:ffff:ffff
752730:4a00::/242730:4aff:ffff:ffff:ffff:ffff:ffff:ffff
762730:4b00::/242730:4bff:ffff:ffff:ffff:ffff:ffff:ffff
772730:4c00::/242730:4cff:ffff:ffff:ffff:ffff:ffff:ffff
782730:4d00::/242730:4dff:ffff:ffff:ffff:ffff:ffff:ffff
792730:4e00::/242730:4eff:ffff:ffff:ffff:ffff:ffff:ffff
802730:4f00::/242730:4fff:ffff:ffff:ffff:ffff:ffff:ffff
812730:5000::/242730:50ff:ffff:ffff:ffff:ffff:ffff:ffff
822730:5100::/242730:51ff:ffff:ffff:ffff:ffff:ffff:ffff
832730:5200::/242730:52ff:ffff:ffff:ffff:ffff:ffff:ffff
842730:5300::/242730:53ff:ffff:ffff:ffff:ffff:ffff:ffff
852730:5400::/242730:54ff:ffff:ffff:ffff:ffff:ffff:ffff
862730:5500::/242730:55ff:ffff:ffff:ffff:ffff:ffff:ffff
872730:5600::/242730:56ff:ffff:ffff:ffff:ffff:ffff:ffff
882730:5700::/242730:57ff:ffff:ffff:ffff:ffff:ffff:ffff
892730:5800::/242730:58ff:ffff:ffff:ffff:ffff:ffff:ffff
902730:5900::/242730:59ff:ffff:ffff:ffff:ffff:ffff:ffff
912730:5a00::/242730:5aff:ffff:ffff:ffff:ffff:ffff:ffff
922730:5b00::/242730:5bff:ffff:ffff:ffff:ffff:ffff:ffff
932730:5c00::/242730:5cff:ffff:ffff:ffff:ffff:ffff:ffff
942730:5d00::/242730:5dff:ffff:ffff:ffff:ffff:ffff:ffff
952730:5e00::/242730:5eff:ffff:ffff:ffff:ffff:ffff:ffff
962730:5f00::/242730:5fff:ffff:ffff:ffff:ffff:ffff:ffff
972730:6000::/242730:60ff:ffff:ffff:ffff:ffff:ffff:ffff
982730:6100::/242730:61ff:ffff:ffff:ffff:ffff:ffff:ffff
992730:6200::/242730:62ff:ffff:ffff:ffff:ffff:ffff:ffff
1002730:6300::/242730:63ff:ffff:ffff:ffff:ffff:ffff:ffff
1012730:6400::/242730:64ff:ffff:ffff:ffff:ffff:ffff:ffff
1022730:6500::/242730:65ff:ffff:ffff:ffff:ffff:ffff:ffff
1032730:6600::/242730:66ff:ffff:ffff:ffff:ffff:ffff:ffff
1042730:6700::/242730:67ff:ffff:ffff:ffff:ffff:ffff:ffff
1052730:6800::/242730:68ff:ffff:ffff:ffff:ffff:ffff:ffff
1062730:6900::/242730:69ff:ffff:ffff:ffff:ffff:ffff:ffff
1072730:6a00::/242730:6aff:ffff:ffff:ffff:ffff:ffff:ffff
1082730:6b00::/242730:6bff:ffff:ffff:ffff:ffff:ffff:ffff
1092730:6c00::/242730:6cff:ffff:ffff:ffff:ffff:ffff:ffff
1102730:6d00::/242730:6dff:ffff:ffff:ffff:ffff:ffff:ffff
1112730:6e00::/242730:6eff:ffff:ffff:ffff:ffff:ffff:ffff
1122730:6f00::/242730:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1132730:7000::/242730:70ff:ffff:ffff:ffff:ffff:ffff:ffff
1142730:7100::/242730:71ff:ffff:ffff:ffff:ffff:ffff:ffff
1152730:7200::/242730:72ff:ffff:ffff:ffff:ffff:ffff:ffff
1162730:7300::/242730:73ff:ffff:ffff:ffff:ffff:ffff:ffff
1172730:7400::/242730:74ff:ffff:ffff:ffff:ffff:ffff:ffff
1182730:7500::/242730:75ff:ffff:ffff:ffff:ffff:ffff:ffff
1192730:7600::/242730:76ff:ffff:ffff:ffff:ffff:ffff:ffff
1202730:7700::/242730:77ff:ffff:ffff:ffff:ffff:ffff:ffff
1212730:7800::/242730:78ff:ffff:ffff:ffff:ffff:ffff:ffff
1222730:7900::/242730:79ff:ffff:ffff:ffff:ffff:ffff:ffff
1232730:7a00::/242730:7aff:ffff:ffff:ffff:ffff:ffff:ffff
1242730:7b00::/242730:7bff:ffff:ffff:ffff:ffff:ffff:ffff
1252730:7c00::/242730:7cff:ffff:ffff:ffff:ffff:ffff:ffff
1262730:7d00::/242730:7dff:ffff:ffff:ffff:ffff:ffff:ffff
1272730:7e00::/242730:7eff:ffff:ffff:ffff:ffff:ffff:ffff
1282730:7f00::/242730:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1292730:8000::/242730:80ff:ffff:ffff:ffff:ffff:ffff:ffff
1302730:8100::/242730:81ff:ffff:ffff:ffff:ffff:ffff:ffff
1312730:8200::/242730:82ff:ffff:ffff:ffff:ffff:ffff:ffff
1322730:8300::/242730:83ff:ffff:ffff:ffff:ffff:ffff:ffff
1332730:8400::/242730:84ff:ffff:ffff:ffff:ffff:ffff:ffff
1342730:8500::/242730:85ff:ffff:ffff:ffff:ffff:ffff:ffff
1352730:8600::/242730:86ff:ffff:ffff:ffff:ffff:ffff:ffff
1362730:8700::/242730:87ff:ffff:ffff:ffff:ffff:ffff:ffff
1372730:8800::/242730:88ff:ffff:ffff:ffff:ffff:ffff:ffff
1382730:8900::/242730:89ff:ffff:ffff:ffff:ffff:ffff:ffff
1392730:8a00::/242730:8aff:ffff:ffff:ffff:ffff:ffff:ffff
1402730:8b00::/242730:8bff:ffff:ffff:ffff:ffff:ffff:ffff
1412730:8c00::/242730:8cff:ffff:ffff:ffff:ffff:ffff:ffff
1422730:8d00::/242730:8dff:ffff:ffff:ffff:ffff:ffff:ffff
1432730:8e00::/242730:8eff:ffff:ffff:ffff:ffff:ffff:ffff
1442730:8f00::/242730:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1452730:9000::/242730:90ff:ffff:ffff:ffff:ffff:ffff:ffff
1462730:9100::/242730:91ff:ffff:ffff:ffff:ffff:ffff:ffff
1472730:9200::/242730:92ff:ffff:ffff:ffff:ffff:ffff:ffff
1482730:9300::/242730:93ff:ffff:ffff:ffff:ffff:ffff:ffff
1492730:9400::/242730:94ff:ffff:ffff:ffff:ffff:ffff:ffff
1502730:9500::/242730:95ff:ffff:ffff:ffff:ffff:ffff:ffff
1512730:9600::/242730:96ff:ffff:ffff:ffff:ffff:ffff:ffff
1522730:9700::/242730:97ff:ffff:ffff:ffff:ffff:ffff:ffff
1532730:9800::/242730:98ff:ffff:ffff:ffff:ffff:ffff:ffff
1542730:9900::/242730:99ff:ffff:ffff:ffff:ffff:ffff:ffff
1552730:9a00::/242730:9aff:ffff:ffff:ffff:ffff:ffff:ffff
1562730:9b00::/242730:9bff:ffff:ffff:ffff:ffff:ffff:ffff
1572730:9c00::/242730:9cff:ffff:ffff:ffff:ffff:ffff:ffff
1582730:9d00::/242730:9dff:ffff:ffff:ffff:ffff:ffff:ffff
1592730:9e00::/242730:9eff:ffff:ffff:ffff:ffff:ffff:ffff
1602730:9f00::/242730:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1612730:a000::/242730:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
1622730:a100::/242730:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
1632730:a200::/242730:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
1642730:a300::/242730:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
1652730:a400::/242730:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
1662730:a500::/242730:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
1672730:a600::/242730:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
1682730:a700::/242730:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
1692730:a800::/242730:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
1702730:a900::/242730:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
1712730:aa00::/242730:aaff:ffff:ffff:ffff:ffff:ffff:ffff
1722730:ab00::/242730:abff:ffff:ffff:ffff:ffff:ffff:ffff
1732730:ac00::/242730:acff:ffff:ffff:ffff:ffff:ffff:ffff
1742730:ad00::/242730:adff:ffff:ffff:ffff:ffff:ffff:ffff
1752730:ae00::/242730:aeff:ffff:ffff:ffff:ffff:ffff:ffff
1762730:af00::/242730:afff:ffff:ffff:ffff:ffff:ffff:ffff
1772730:b000::/242730:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
1782730:b100::/242730:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
1792730:b200::/242730:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
1802730:b300::/242730:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
1812730:b400::/242730:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
1822730:b500::/242730:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
1832730:b600::/242730:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
1842730:b700::/242730:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
1852730:b800::/242730:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
1862730:b900::/242730:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
1872730:ba00::/242730:baff:ffff:ffff:ffff:ffff:ffff:ffff
1882730:bb00::/242730:bbff:ffff:ffff:ffff:ffff:ffff:ffff
1892730:bc00::/242730:bcff:ffff:ffff:ffff:ffff:ffff:ffff
1902730:bd00::/242730:bdff:ffff:ffff:ffff:ffff:ffff:ffff
1912730:be00::/242730:beff:ffff:ffff:ffff:ffff:ffff:ffff
1922730:bf00::/242730:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1932730:c000::/242730:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
1942730:c100::/242730:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
1952730:c200::/242730:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
1962730:c300::/242730:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
1972730:c400::/242730:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
1982730:c500::/242730:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
1992730:c600::/242730:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
2002730:c700::/242730:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
2012730:c800::/242730:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
2022730:c900::/242730:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
2032730:ca00::/242730:caff:ffff:ffff:ffff:ffff:ffff:ffff
2042730:cb00::/242730:cbff:ffff:ffff:ffff:ffff:ffff:ffff
2052730:cc00::/242730:ccff:ffff:ffff:ffff:ffff:ffff:ffff
2062730:cd00::/242730:cdff:ffff:ffff:ffff:ffff:ffff:ffff
2072730:ce00::/242730:ceff:ffff:ffff:ffff:ffff:ffff:ffff
2082730:cf00::/242730:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2092730:d000::/242730:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
2102730:d100::/242730:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
2112730:d200::/242730:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
2122730:d300::/242730:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
2132730:d400::/242730:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
2142730:d500::/242730:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
2152730:d600::/242730:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
2162730:d700::/242730:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
2172730:d800::/242730:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
2182730:d900::/242730:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
2192730:da00::/242730:daff:ffff:ffff:ffff:ffff:ffff:ffff
2202730:db00::/242730:dbff:ffff:ffff:ffff:ffff:ffff:ffff
2212730:dc00::/242730:dcff:ffff:ffff:ffff:ffff:ffff:ffff
2222730:dd00::/242730:ddff:ffff:ffff:ffff:ffff:ffff:ffff
2232730:de00::/242730:deff:ffff:ffff:ffff:ffff:ffff:ffff
2242730:df00::/242730:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2252730:e000::/242730:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
2262730:e100::/242730:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
2272730:e200::/242730:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
2282730:e300::/242730:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
2292730:e400::/242730:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
2302730:e500::/242730:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
2312730:e600::/242730:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
2322730:e700::/242730:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
2332730:e800::/242730:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
2342730:e900::/242730:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
2352730:ea00::/242730:eaff:ffff:ffff:ffff:ffff:ffff:ffff
2362730:eb00::/242730:ebff:ffff:ffff:ffff:ffff:ffff:ffff
2372730:ec00::/242730:ecff:ffff:ffff:ffff:ffff:ffff:ffff
2382730:ed00::/242730:edff:ffff:ffff:ffff:ffff:ffff:ffff
2392730:ee00::/242730:eeff:ffff:ffff:ffff:ffff:ffff:ffff
2402730:ef00::/242730:efff:ffff:ffff:ffff:ffff:ffff:ffff
2412730:f000::/242730:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
2422730:f100::/242730:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
2432730:f200::/242730:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
2442730:f300::/242730:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
2452730:f400::/242730:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
2462730:f500::/242730:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
2472730:f600::/242730:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
2482730:f700::/242730:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
2492730:f800::/242730:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
2502730:f900::/242730:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
2512730:fa00::/242730:faff:ffff:ffff:ffff:ffff:ffff:ffff
2522730:fb00::/242730:fbff:ffff:ffff:ffff:ffff:ffff:ffff
2532730:fc00::/242730:fcff:ffff:ffff:ffff:ffff:ffff:ffff
2542730:fd00::/242730:fdff:ffff:ffff:ffff:ffff:ffff:ffff
2552730:fe00::/242730:feff:ffff:ffff:ffff:ffff:ffff:ffff
2562730:ff00::/242730: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.