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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
2780::/12
First address
2780::
Last address
278f: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
2780:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
8.7.2.ip6.arpa
Split into smaller subnets/24
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

2780::/12 makes 4,096 subnets of /24; the first 256 are listed.

Subnets
#SubnetLast address
12780::/242780:ff:ffff:ffff:ffff:ffff:ffff:ffff
22780:100::/242780:1ff:ffff:ffff:ffff:ffff:ffff:ffff
32780:200::/242780:2ff:ffff:ffff:ffff:ffff:ffff:ffff
42780:300::/242780:3ff:ffff:ffff:ffff:ffff:ffff:ffff
52780:400::/242780:4ff:ffff:ffff:ffff:ffff:ffff:ffff
62780:500::/242780:5ff:ffff:ffff:ffff:ffff:ffff:ffff
72780:600::/242780:6ff:ffff:ffff:ffff:ffff:ffff:ffff
82780:700::/242780:7ff:ffff:ffff:ffff:ffff:ffff:ffff
92780:800::/242780:8ff:ffff:ffff:ffff:ffff:ffff:ffff
102780:900::/242780:9ff:ffff:ffff:ffff:ffff:ffff:ffff
112780:a00::/242780:aff:ffff:ffff:ffff:ffff:ffff:ffff
122780:b00::/242780:bff:ffff:ffff:ffff:ffff:ffff:ffff
132780:c00::/242780:cff:ffff:ffff:ffff:ffff:ffff:ffff
142780:d00::/242780:dff:ffff:ffff:ffff:ffff:ffff:ffff
152780:e00::/242780:eff:ffff:ffff:ffff:ffff:ffff:ffff
162780:f00::/242780:fff:ffff:ffff:ffff:ffff:ffff:ffff
172780:1000::/242780:10ff:ffff:ffff:ffff:ffff:ffff:ffff
182780:1100::/242780:11ff:ffff:ffff:ffff:ffff:ffff:ffff
192780:1200::/242780:12ff:ffff:ffff:ffff:ffff:ffff:ffff
202780:1300::/242780:13ff:ffff:ffff:ffff:ffff:ffff:ffff
212780:1400::/242780:14ff:ffff:ffff:ffff:ffff:ffff:ffff
222780:1500::/242780:15ff:ffff:ffff:ffff:ffff:ffff:ffff
232780:1600::/242780:16ff:ffff:ffff:ffff:ffff:ffff:ffff
242780:1700::/242780:17ff:ffff:ffff:ffff:ffff:ffff:ffff
252780:1800::/242780:18ff:ffff:ffff:ffff:ffff:ffff:ffff
262780:1900::/242780:19ff:ffff:ffff:ffff:ffff:ffff:ffff
272780:1a00::/242780:1aff:ffff:ffff:ffff:ffff:ffff:ffff
282780:1b00::/242780:1bff:ffff:ffff:ffff:ffff:ffff:ffff
292780:1c00::/242780:1cff:ffff:ffff:ffff:ffff:ffff:ffff
302780:1d00::/242780:1dff:ffff:ffff:ffff:ffff:ffff:ffff
312780:1e00::/242780:1eff:ffff:ffff:ffff:ffff:ffff:ffff
322780:1f00::/242780:1fff:ffff:ffff:ffff:ffff:ffff:ffff
332780:2000::/242780:20ff:ffff:ffff:ffff:ffff:ffff:ffff
342780:2100::/242780:21ff:ffff:ffff:ffff:ffff:ffff:ffff
352780:2200::/242780:22ff:ffff:ffff:ffff:ffff:ffff:ffff
362780:2300::/242780:23ff:ffff:ffff:ffff:ffff:ffff:ffff
372780:2400::/242780:24ff:ffff:ffff:ffff:ffff:ffff:ffff
382780:2500::/242780:25ff:ffff:ffff:ffff:ffff:ffff:ffff
392780:2600::/242780:26ff:ffff:ffff:ffff:ffff:ffff:ffff
402780:2700::/242780:27ff:ffff:ffff:ffff:ffff:ffff:ffff
412780:2800::/242780:28ff:ffff:ffff:ffff:ffff:ffff:ffff
422780:2900::/242780:29ff:ffff:ffff:ffff:ffff:ffff:ffff
432780:2a00::/242780:2aff:ffff:ffff:ffff:ffff:ffff:ffff
442780:2b00::/242780:2bff:ffff:ffff:ffff:ffff:ffff:ffff
452780:2c00::/242780:2cff:ffff:ffff:ffff:ffff:ffff:ffff
462780:2d00::/242780:2dff:ffff:ffff:ffff:ffff:ffff:ffff
472780:2e00::/242780:2eff:ffff:ffff:ffff:ffff:ffff:ffff
482780:2f00::/242780:2fff:ffff:ffff:ffff:ffff:ffff:ffff
492780:3000::/242780:30ff:ffff:ffff:ffff:ffff:ffff:ffff
502780:3100::/242780:31ff:ffff:ffff:ffff:ffff:ffff:ffff
512780:3200::/242780:32ff:ffff:ffff:ffff:ffff:ffff:ffff
522780:3300::/242780:33ff:ffff:ffff:ffff:ffff:ffff:ffff
532780:3400::/242780:34ff:ffff:ffff:ffff:ffff:ffff:ffff
542780:3500::/242780:35ff:ffff:ffff:ffff:ffff:ffff:ffff
552780:3600::/242780:36ff:ffff:ffff:ffff:ffff:ffff:ffff
562780:3700::/242780:37ff:ffff:ffff:ffff:ffff:ffff:ffff
572780:3800::/242780:38ff:ffff:ffff:ffff:ffff:ffff:ffff
582780:3900::/242780:39ff:ffff:ffff:ffff:ffff:ffff:ffff
592780:3a00::/242780:3aff:ffff:ffff:ffff:ffff:ffff:ffff
602780:3b00::/242780:3bff:ffff:ffff:ffff:ffff:ffff:ffff
612780:3c00::/242780:3cff:ffff:ffff:ffff:ffff:ffff:ffff
622780:3d00::/242780:3dff:ffff:ffff:ffff:ffff:ffff:ffff
632780:3e00::/242780:3eff:ffff:ffff:ffff:ffff:ffff:ffff
642780:3f00::/242780:3fff:ffff:ffff:ffff:ffff:ffff:ffff
652780:4000::/242780:40ff:ffff:ffff:ffff:ffff:ffff:ffff
662780:4100::/242780:41ff:ffff:ffff:ffff:ffff:ffff:ffff
672780:4200::/242780:42ff:ffff:ffff:ffff:ffff:ffff:ffff
682780:4300::/242780:43ff:ffff:ffff:ffff:ffff:ffff:ffff
692780:4400::/242780:44ff:ffff:ffff:ffff:ffff:ffff:ffff
702780:4500::/242780:45ff:ffff:ffff:ffff:ffff:ffff:ffff
712780:4600::/242780:46ff:ffff:ffff:ffff:ffff:ffff:ffff
722780:4700::/242780:47ff:ffff:ffff:ffff:ffff:ffff:ffff
732780:4800::/242780:48ff:ffff:ffff:ffff:ffff:ffff:ffff
742780:4900::/242780:49ff:ffff:ffff:ffff:ffff:ffff:ffff
752780:4a00::/242780:4aff:ffff:ffff:ffff:ffff:ffff:ffff
762780:4b00::/242780:4bff:ffff:ffff:ffff:ffff:ffff:ffff
772780:4c00::/242780:4cff:ffff:ffff:ffff:ffff:ffff:ffff
782780:4d00::/242780:4dff:ffff:ffff:ffff:ffff:ffff:ffff
792780:4e00::/242780:4eff:ffff:ffff:ffff:ffff:ffff:ffff
802780:4f00::/242780:4fff:ffff:ffff:ffff:ffff:ffff:ffff
812780:5000::/242780:50ff:ffff:ffff:ffff:ffff:ffff:ffff
822780:5100::/242780:51ff:ffff:ffff:ffff:ffff:ffff:ffff
832780:5200::/242780:52ff:ffff:ffff:ffff:ffff:ffff:ffff
842780:5300::/242780:53ff:ffff:ffff:ffff:ffff:ffff:ffff
852780:5400::/242780:54ff:ffff:ffff:ffff:ffff:ffff:ffff
862780:5500::/242780:55ff:ffff:ffff:ffff:ffff:ffff:ffff
872780:5600::/242780:56ff:ffff:ffff:ffff:ffff:ffff:ffff
882780:5700::/242780:57ff:ffff:ffff:ffff:ffff:ffff:ffff
892780:5800::/242780:58ff:ffff:ffff:ffff:ffff:ffff:ffff
902780:5900::/242780:59ff:ffff:ffff:ffff:ffff:ffff:ffff
912780:5a00::/242780:5aff:ffff:ffff:ffff:ffff:ffff:ffff
922780:5b00::/242780:5bff:ffff:ffff:ffff:ffff:ffff:ffff
932780:5c00::/242780:5cff:ffff:ffff:ffff:ffff:ffff:ffff
942780:5d00::/242780:5dff:ffff:ffff:ffff:ffff:ffff:ffff
952780:5e00::/242780:5eff:ffff:ffff:ffff:ffff:ffff:ffff
962780:5f00::/242780:5fff:ffff:ffff:ffff:ffff:ffff:ffff
972780:6000::/242780:60ff:ffff:ffff:ffff:ffff:ffff:ffff
982780:6100::/242780:61ff:ffff:ffff:ffff:ffff:ffff:ffff
992780:6200::/242780:62ff:ffff:ffff:ffff:ffff:ffff:ffff
1002780:6300::/242780:63ff:ffff:ffff:ffff:ffff:ffff:ffff
1012780:6400::/242780:64ff:ffff:ffff:ffff:ffff:ffff:ffff
1022780:6500::/242780:65ff:ffff:ffff:ffff:ffff:ffff:ffff
1032780:6600::/242780:66ff:ffff:ffff:ffff:ffff:ffff:ffff
1042780:6700::/242780:67ff:ffff:ffff:ffff:ffff:ffff:ffff
1052780:6800::/242780:68ff:ffff:ffff:ffff:ffff:ffff:ffff
1062780:6900::/242780:69ff:ffff:ffff:ffff:ffff:ffff:ffff
1072780:6a00::/242780:6aff:ffff:ffff:ffff:ffff:ffff:ffff
1082780:6b00::/242780:6bff:ffff:ffff:ffff:ffff:ffff:ffff
1092780:6c00::/242780:6cff:ffff:ffff:ffff:ffff:ffff:ffff
1102780:6d00::/242780:6dff:ffff:ffff:ffff:ffff:ffff:ffff
1112780:6e00::/242780:6eff:ffff:ffff:ffff:ffff:ffff:ffff
1122780:6f00::/242780:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1132780:7000::/242780:70ff:ffff:ffff:ffff:ffff:ffff:ffff
1142780:7100::/242780:71ff:ffff:ffff:ffff:ffff:ffff:ffff
1152780:7200::/242780:72ff:ffff:ffff:ffff:ffff:ffff:ffff
1162780:7300::/242780:73ff:ffff:ffff:ffff:ffff:ffff:ffff
1172780:7400::/242780:74ff:ffff:ffff:ffff:ffff:ffff:ffff
1182780:7500::/242780:75ff:ffff:ffff:ffff:ffff:ffff:ffff
1192780:7600::/242780:76ff:ffff:ffff:ffff:ffff:ffff:ffff
1202780:7700::/242780:77ff:ffff:ffff:ffff:ffff:ffff:ffff
1212780:7800::/242780:78ff:ffff:ffff:ffff:ffff:ffff:ffff
1222780:7900::/242780:79ff:ffff:ffff:ffff:ffff:ffff:ffff
1232780:7a00::/242780:7aff:ffff:ffff:ffff:ffff:ffff:ffff
1242780:7b00::/242780:7bff:ffff:ffff:ffff:ffff:ffff:ffff
1252780:7c00::/242780:7cff:ffff:ffff:ffff:ffff:ffff:ffff
1262780:7d00::/242780:7dff:ffff:ffff:ffff:ffff:ffff:ffff
1272780:7e00::/242780:7eff:ffff:ffff:ffff:ffff:ffff:ffff
1282780:7f00::/242780:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1292780:8000::/242780:80ff:ffff:ffff:ffff:ffff:ffff:ffff
1302780:8100::/242780:81ff:ffff:ffff:ffff:ffff:ffff:ffff
1312780:8200::/242780:82ff:ffff:ffff:ffff:ffff:ffff:ffff
1322780:8300::/242780:83ff:ffff:ffff:ffff:ffff:ffff:ffff
1332780:8400::/242780:84ff:ffff:ffff:ffff:ffff:ffff:ffff
1342780:8500::/242780:85ff:ffff:ffff:ffff:ffff:ffff:ffff
1352780:8600::/242780:86ff:ffff:ffff:ffff:ffff:ffff:ffff
1362780:8700::/242780:87ff:ffff:ffff:ffff:ffff:ffff:ffff
1372780:8800::/242780:88ff:ffff:ffff:ffff:ffff:ffff:ffff
1382780:8900::/242780:89ff:ffff:ffff:ffff:ffff:ffff:ffff
1392780:8a00::/242780:8aff:ffff:ffff:ffff:ffff:ffff:ffff
1402780:8b00::/242780:8bff:ffff:ffff:ffff:ffff:ffff:ffff
1412780:8c00::/242780:8cff:ffff:ffff:ffff:ffff:ffff:ffff
1422780:8d00::/242780:8dff:ffff:ffff:ffff:ffff:ffff:ffff
1432780:8e00::/242780:8eff:ffff:ffff:ffff:ffff:ffff:ffff
1442780:8f00::/242780:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1452780:9000::/242780:90ff:ffff:ffff:ffff:ffff:ffff:ffff
1462780:9100::/242780:91ff:ffff:ffff:ffff:ffff:ffff:ffff
1472780:9200::/242780:92ff:ffff:ffff:ffff:ffff:ffff:ffff
1482780:9300::/242780:93ff:ffff:ffff:ffff:ffff:ffff:ffff
1492780:9400::/242780:94ff:ffff:ffff:ffff:ffff:ffff:ffff
1502780:9500::/242780:95ff:ffff:ffff:ffff:ffff:ffff:ffff
1512780:9600::/242780:96ff:ffff:ffff:ffff:ffff:ffff:ffff
1522780:9700::/242780:97ff:ffff:ffff:ffff:ffff:ffff:ffff
1532780:9800::/242780:98ff:ffff:ffff:ffff:ffff:ffff:ffff
1542780:9900::/242780:99ff:ffff:ffff:ffff:ffff:ffff:ffff
1552780:9a00::/242780:9aff:ffff:ffff:ffff:ffff:ffff:ffff
1562780:9b00::/242780:9bff:ffff:ffff:ffff:ffff:ffff:ffff
1572780:9c00::/242780:9cff:ffff:ffff:ffff:ffff:ffff:ffff
1582780:9d00::/242780:9dff:ffff:ffff:ffff:ffff:ffff:ffff
1592780:9e00::/242780:9eff:ffff:ffff:ffff:ffff:ffff:ffff
1602780:9f00::/242780:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1612780:a000::/242780:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
1622780:a100::/242780:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
1632780:a200::/242780:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
1642780:a300::/242780:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
1652780:a400::/242780:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
1662780:a500::/242780:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
1672780:a600::/242780:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
1682780:a700::/242780:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
1692780:a800::/242780:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
1702780:a900::/242780:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
1712780:aa00::/242780:aaff:ffff:ffff:ffff:ffff:ffff:ffff
1722780:ab00::/242780:abff:ffff:ffff:ffff:ffff:ffff:ffff
1732780:ac00::/242780:acff:ffff:ffff:ffff:ffff:ffff:ffff
1742780:ad00::/242780:adff:ffff:ffff:ffff:ffff:ffff:ffff
1752780:ae00::/242780:aeff:ffff:ffff:ffff:ffff:ffff:ffff
1762780:af00::/242780:afff:ffff:ffff:ffff:ffff:ffff:ffff
1772780:b000::/242780:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
1782780:b100::/242780:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
1792780:b200::/242780:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
1802780:b300::/242780:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
1812780:b400::/242780:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
1822780:b500::/242780:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
1832780:b600::/242780:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
1842780:b700::/242780:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
1852780:b800::/242780:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
1862780:b900::/242780:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
1872780:ba00::/242780:baff:ffff:ffff:ffff:ffff:ffff:ffff
1882780:bb00::/242780:bbff:ffff:ffff:ffff:ffff:ffff:ffff
1892780:bc00::/242780:bcff:ffff:ffff:ffff:ffff:ffff:ffff
1902780:bd00::/242780:bdff:ffff:ffff:ffff:ffff:ffff:ffff
1912780:be00::/242780:beff:ffff:ffff:ffff:ffff:ffff:ffff
1922780:bf00::/242780:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1932780:c000::/242780:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
1942780:c100::/242780:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
1952780:c200::/242780:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
1962780:c300::/242780:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
1972780:c400::/242780:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
1982780:c500::/242780:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
1992780:c600::/242780:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
2002780:c700::/242780:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
2012780:c800::/242780:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
2022780:c900::/242780:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
2032780:ca00::/242780:caff:ffff:ffff:ffff:ffff:ffff:ffff
2042780:cb00::/242780:cbff:ffff:ffff:ffff:ffff:ffff:ffff
2052780:cc00::/242780:ccff:ffff:ffff:ffff:ffff:ffff:ffff
2062780:cd00::/242780:cdff:ffff:ffff:ffff:ffff:ffff:ffff
2072780:ce00::/242780:ceff:ffff:ffff:ffff:ffff:ffff:ffff
2082780:cf00::/242780:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2092780:d000::/242780:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
2102780:d100::/242780:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
2112780:d200::/242780:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
2122780:d300::/242780:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
2132780:d400::/242780:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
2142780:d500::/242780:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
2152780:d600::/242780:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
2162780:d700::/242780:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
2172780:d800::/242780:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
2182780:d900::/242780:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
2192780:da00::/242780:daff:ffff:ffff:ffff:ffff:ffff:ffff
2202780:db00::/242780:dbff:ffff:ffff:ffff:ffff:ffff:ffff
2212780:dc00::/242780:dcff:ffff:ffff:ffff:ffff:ffff:ffff
2222780:dd00::/242780:ddff:ffff:ffff:ffff:ffff:ffff:ffff
2232780:de00::/242780:deff:ffff:ffff:ffff:ffff:ffff:ffff
2242780:df00::/242780:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2252780:e000::/242780:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
2262780:e100::/242780:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
2272780:e200::/242780:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
2282780:e300::/242780:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
2292780:e400::/242780:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
2302780:e500::/242780:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
2312780:e600::/242780:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
2322780:e700::/242780:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
2332780:e800::/242780:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
2342780:e900::/242780:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
2352780:ea00::/242780:eaff:ffff:ffff:ffff:ffff:ffff:ffff
2362780:eb00::/242780:ebff:ffff:ffff:ffff:ffff:ffff:ffff
2372780:ec00::/242780:ecff:ffff:ffff:ffff:ffff:ffff:ffff
2382780:ed00::/242780:edff:ffff:ffff:ffff:ffff:ffff:ffff
2392780:ee00::/242780:eeff:ffff:ffff:ffff:ffff:ffff:ffff
2402780:ef00::/242780:efff:ffff:ffff:ffff:ffff:ffff:ffff
2412780:f000::/242780:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
2422780:f100::/242780:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
2432780:f200::/242780:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
2442780:f300::/242780:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
2452780:f400::/242780:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
2462780:f500::/242780:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
2472780:f600::/242780:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
2482780:f700::/242780:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
2492780:f800::/242780:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
2502780:f900::/242780:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
2512780:fa00::/242780:faff:ffff:ffff:ffff:ffff:ffff:ffff
2522780:fb00::/242780:fbff:ffff:ffff:ffff:ffff:ffff:ffff
2532780:fc00::/242780:fcff:ffff:ffff:ffff:ffff:ffff:ffff
2542780:fd00::/242780:fdff:ffff:ffff:ffff:ffff:ffff:ffff
2552780:fe00::/242780:feff:ffff:ffff:ffff:ffff:ffff:ffff
2562780:ff00::/242780: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.