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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
2ec2::/16
First address
2ec2::
Last address
2ec2: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
2ec2:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
2.c.e.2.ip6.arpa
Split into smaller subnets/24
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

2ec2::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
12ec2::/242ec2:ff:ffff:ffff:ffff:ffff:ffff:ffff
22ec2:100::/242ec2:1ff:ffff:ffff:ffff:ffff:ffff:ffff
32ec2:200::/242ec2:2ff:ffff:ffff:ffff:ffff:ffff:ffff
42ec2:300::/242ec2:3ff:ffff:ffff:ffff:ffff:ffff:ffff
52ec2:400::/242ec2:4ff:ffff:ffff:ffff:ffff:ffff:ffff
62ec2:500::/242ec2:5ff:ffff:ffff:ffff:ffff:ffff:ffff
72ec2:600::/242ec2:6ff:ffff:ffff:ffff:ffff:ffff:ffff
82ec2:700::/242ec2:7ff:ffff:ffff:ffff:ffff:ffff:ffff
92ec2:800::/242ec2:8ff:ffff:ffff:ffff:ffff:ffff:ffff
102ec2:900::/242ec2:9ff:ffff:ffff:ffff:ffff:ffff:ffff
112ec2:a00::/242ec2:aff:ffff:ffff:ffff:ffff:ffff:ffff
122ec2:b00::/242ec2:bff:ffff:ffff:ffff:ffff:ffff:ffff
132ec2:c00::/242ec2:cff:ffff:ffff:ffff:ffff:ffff:ffff
142ec2:d00::/242ec2:dff:ffff:ffff:ffff:ffff:ffff:ffff
152ec2:e00::/242ec2:eff:ffff:ffff:ffff:ffff:ffff:ffff
162ec2:f00::/242ec2:fff:ffff:ffff:ffff:ffff:ffff:ffff
172ec2:1000::/242ec2:10ff:ffff:ffff:ffff:ffff:ffff:ffff
182ec2:1100::/242ec2:11ff:ffff:ffff:ffff:ffff:ffff:ffff
192ec2:1200::/242ec2:12ff:ffff:ffff:ffff:ffff:ffff:ffff
202ec2:1300::/242ec2:13ff:ffff:ffff:ffff:ffff:ffff:ffff
212ec2:1400::/242ec2:14ff:ffff:ffff:ffff:ffff:ffff:ffff
222ec2:1500::/242ec2:15ff:ffff:ffff:ffff:ffff:ffff:ffff
232ec2:1600::/242ec2:16ff:ffff:ffff:ffff:ffff:ffff:ffff
242ec2:1700::/242ec2:17ff:ffff:ffff:ffff:ffff:ffff:ffff
252ec2:1800::/242ec2:18ff:ffff:ffff:ffff:ffff:ffff:ffff
262ec2:1900::/242ec2:19ff:ffff:ffff:ffff:ffff:ffff:ffff
272ec2:1a00::/242ec2:1aff:ffff:ffff:ffff:ffff:ffff:ffff
282ec2:1b00::/242ec2:1bff:ffff:ffff:ffff:ffff:ffff:ffff
292ec2:1c00::/242ec2:1cff:ffff:ffff:ffff:ffff:ffff:ffff
302ec2:1d00::/242ec2:1dff:ffff:ffff:ffff:ffff:ffff:ffff
312ec2:1e00::/242ec2:1eff:ffff:ffff:ffff:ffff:ffff:ffff
322ec2:1f00::/242ec2:1fff:ffff:ffff:ffff:ffff:ffff:ffff
332ec2:2000::/242ec2:20ff:ffff:ffff:ffff:ffff:ffff:ffff
342ec2:2100::/242ec2:21ff:ffff:ffff:ffff:ffff:ffff:ffff
352ec2:2200::/242ec2:22ff:ffff:ffff:ffff:ffff:ffff:ffff
362ec2:2300::/242ec2:23ff:ffff:ffff:ffff:ffff:ffff:ffff
372ec2:2400::/242ec2:24ff:ffff:ffff:ffff:ffff:ffff:ffff
382ec2:2500::/242ec2:25ff:ffff:ffff:ffff:ffff:ffff:ffff
392ec2:2600::/242ec2:26ff:ffff:ffff:ffff:ffff:ffff:ffff
402ec2:2700::/242ec2:27ff:ffff:ffff:ffff:ffff:ffff:ffff
412ec2:2800::/242ec2:28ff:ffff:ffff:ffff:ffff:ffff:ffff
422ec2:2900::/242ec2:29ff:ffff:ffff:ffff:ffff:ffff:ffff
432ec2:2a00::/242ec2:2aff:ffff:ffff:ffff:ffff:ffff:ffff
442ec2:2b00::/242ec2:2bff:ffff:ffff:ffff:ffff:ffff:ffff
452ec2:2c00::/242ec2:2cff:ffff:ffff:ffff:ffff:ffff:ffff
462ec2:2d00::/242ec2:2dff:ffff:ffff:ffff:ffff:ffff:ffff
472ec2:2e00::/242ec2:2eff:ffff:ffff:ffff:ffff:ffff:ffff
482ec2:2f00::/242ec2:2fff:ffff:ffff:ffff:ffff:ffff:ffff
492ec2:3000::/242ec2:30ff:ffff:ffff:ffff:ffff:ffff:ffff
502ec2:3100::/242ec2:31ff:ffff:ffff:ffff:ffff:ffff:ffff
512ec2:3200::/242ec2:32ff:ffff:ffff:ffff:ffff:ffff:ffff
522ec2:3300::/242ec2:33ff:ffff:ffff:ffff:ffff:ffff:ffff
532ec2:3400::/242ec2:34ff:ffff:ffff:ffff:ffff:ffff:ffff
542ec2:3500::/242ec2:35ff:ffff:ffff:ffff:ffff:ffff:ffff
552ec2:3600::/242ec2:36ff:ffff:ffff:ffff:ffff:ffff:ffff
562ec2:3700::/242ec2:37ff:ffff:ffff:ffff:ffff:ffff:ffff
572ec2:3800::/242ec2:38ff:ffff:ffff:ffff:ffff:ffff:ffff
582ec2:3900::/242ec2:39ff:ffff:ffff:ffff:ffff:ffff:ffff
592ec2:3a00::/242ec2:3aff:ffff:ffff:ffff:ffff:ffff:ffff
602ec2:3b00::/242ec2:3bff:ffff:ffff:ffff:ffff:ffff:ffff
612ec2:3c00::/242ec2:3cff:ffff:ffff:ffff:ffff:ffff:ffff
622ec2:3d00::/242ec2:3dff:ffff:ffff:ffff:ffff:ffff:ffff
632ec2:3e00::/242ec2:3eff:ffff:ffff:ffff:ffff:ffff:ffff
642ec2:3f00::/242ec2:3fff:ffff:ffff:ffff:ffff:ffff:ffff
652ec2:4000::/242ec2:40ff:ffff:ffff:ffff:ffff:ffff:ffff
662ec2:4100::/242ec2:41ff:ffff:ffff:ffff:ffff:ffff:ffff
672ec2:4200::/242ec2:42ff:ffff:ffff:ffff:ffff:ffff:ffff
682ec2:4300::/242ec2:43ff:ffff:ffff:ffff:ffff:ffff:ffff
692ec2:4400::/242ec2:44ff:ffff:ffff:ffff:ffff:ffff:ffff
702ec2:4500::/242ec2:45ff:ffff:ffff:ffff:ffff:ffff:ffff
712ec2:4600::/242ec2:46ff:ffff:ffff:ffff:ffff:ffff:ffff
722ec2:4700::/242ec2:47ff:ffff:ffff:ffff:ffff:ffff:ffff
732ec2:4800::/242ec2:48ff:ffff:ffff:ffff:ffff:ffff:ffff
742ec2:4900::/242ec2:49ff:ffff:ffff:ffff:ffff:ffff:ffff
752ec2:4a00::/242ec2:4aff:ffff:ffff:ffff:ffff:ffff:ffff
762ec2:4b00::/242ec2:4bff:ffff:ffff:ffff:ffff:ffff:ffff
772ec2:4c00::/242ec2:4cff:ffff:ffff:ffff:ffff:ffff:ffff
782ec2:4d00::/242ec2:4dff:ffff:ffff:ffff:ffff:ffff:ffff
792ec2:4e00::/242ec2:4eff:ffff:ffff:ffff:ffff:ffff:ffff
802ec2:4f00::/242ec2:4fff:ffff:ffff:ffff:ffff:ffff:ffff
812ec2:5000::/242ec2:50ff:ffff:ffff:ffff:ffff:ffff:ffff
822ec2:5100::/242ec2:51ff:ffff:ffff:ffff:ffff:ffff:ffff
832ec2:5200::/242ec2:52ff:ffff:ffff:ffff:ffff:ffff:ffff
842ec2:5300::/242ec2:53ff:ffff:ffff:ffff:ffff:ffff:ffff
852ec2:5400::/242ec2:54ff:ffff:ffff:ffff:ffff:ffff:ffff
862ec2:5500::/242ec2:55ff:ffff:ffff:ffff:ffff:ffff:ffff
872ec2:5600::/242ec2:56ff:ffff:ffff:ffff:ffff:ffff:ffff
882ec2:5700::/242ec2:57ff:ffff:ffff:ffff:ffff:ffff:ffff
892ec2:5800::/242ec2:58ff:ffff:ffff:ffff:ffff:ffff:ffff
902ec2:5900::/242ec2:59ff:ffff:ffff:ffff:ffff:ffff:ffff
912ec2:5a00::/242ec2:5aff:ffff:ffff:ffff:ffff:ffff:ffff
922ec2:5b00::/242ec2:5bff:ffff:ffff:ffff:ffff:ffff:ffff
932ec2:5c00::/242ec2:5cff:ffff:ffff:ffff:ffff:ffff:ffff
942ec2:5d00::/242ec2:5dff:ffff:ffff:ffff:ffff:ffff:ffff
952ec2:5e00::/242ec2:5eff:ffff:ffff:ffff:ffff:ffff:ffff
962ec2:5f00::/242ec2:5fff:ffff:ffff:ffff:ffff:ffff:ffff
972ec2:6000::/242ec2:60ff:ffff:ffff:ffff:ffff:ffff:ffff
982ec2:6100::/242ec2:61ff:ffff:ffff:ffff:ffff:ffff:ffff
992ec2:6200::/242ec2:62ff:ffff:ffff:ffff:ffff:ffff:ffff
1002ec2:6300::/242ec2:63ff:ffff:ffff:ffff:ffff:ffff:ffff
1012ec2:6400::/242ec2:64ff:ffff:ffff:ffff:ffff:ffff:ffff
1022ec2:6500::/242ec2:65ff:ffff:ffff:ffff:ffff:ffff:ffff
1032ec2:6600::/242ec2:66ff:ffff:ffff:ffff:ffff:ffff:ffff
1042ec2:6700::/242ec2:67ff:ffff:ffff:ffff:ffff:ffff:ffff
1052ec2:6800::/242ec2:68ff:ffff:ffff:ffff:ffff:ffff:ffff
1062ec2:6900::/242ec2:69ff:ffff:ffff:ffff:ffff:ffff:ffff
1072ec2:6a00::/242ec2:6aff:ffff:ffff:ffff:ffff:ffff:ffff
1082ec2:6b00::/242ec2:6bff:ffff:ffff:ffff:ffff:ffff:ffff
1092ec2:6c00::/242ec2:6cff:ffff:ffff:ffff:ffff:ffff:ffff
1102ec2:6d00::/242ec2:6dff:ffff:ffff:ffff:ffff:ffff:ffff
1112ec2:6e00::/242ec2:6eff:ffff:ffff:ffff:ffff:ffff:ffff
1122ec2:6f00::/242ec2:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1132ec2:7000::/242ec2:70ff:ffff:ffff:ffff:ffff:ffff:ffff
1142ec2:7100::/242ec2:71ff:ffff:ffff:ffff:ffff:ffff:ffff
1152ec2:7200::/242ec2:72ff:ffff:ffff:ffff:ffff:ffff:ffff
1162ec2:7300::/242ec2:73ff:ffff:ffff:ffff:ffff:ffff:ffff
1172ec2:7400::/242ec2:74ff:ffff:ffff:ffff:ffff:ffff:ffff
1182ec2:7500::/242ec2:75ff:ffff:ffff:ffff:ffff:ffff:ffff
1192ec2:7600::/242ec2:76ff:ffff:ffff:ffff:ffff:ffff:ffff
1202ec2:7700::/242ec2:77ff:ffff:ffff:ffff:ffff:ffff:ffff
1212ec2:7800::/242ec2:78ff:ffff:ffff:ffff:ffff:ffff:ffff
1222ec2:7900::/242ec2:79ff:ffff:ffff:ffff:ffff:ffff:ffff
1232ec2:7a00::/242ec2:7aff:ffff:ffff:ffff:ffff:ffff:ffff
1242ec2:7b00::/242ec2:7bff:ffff:ffff:ffff:ffff:ffff:ffff
1252ec2:7c00::/242ec2:7cff:ffff:ffff:ffff:ffff:ffff:ffff
1262ec2:7d00::/242ec2:7dff:ffff:ffff:ffff:ffff:ffff:ffff
1272ec2:7e00::/242ec2:7eff:ffff:ffff:ffff:ffff:ffff:ffff
1282ec2:7f00::/242ec2:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1292ec2:8000::/242ec2:80ff:ffff:ffff:ffff:ffff:ffff:ffff
1302ec2:8100::/242ec2:81ff:ffff:ffff:ffff:ffff:ffff:ffff
1312ec2:8200::/242ec2:82ff:ffff:ffff:ffff:ffff:ffff:ffff
1322ec2:8300::/242ec2:83ff:ffff:ffff:ffff:ffff:ffff:ffff
1332ec2:8400::/242ec2:84ff:ffff:ffff:ffff:ffff:ffff:ffff
1342ec2:8500::/242ec2:85ff:ffff:ffff:ffff:ffff:ffff:ffff
1352ec2:8600::/242ec2:86ff:ffff:ffff:ffff:ffff:ffff:ffff
1362ec2:8700::/242ec2:87ff:ffff:ffff:ffff:ffff:ffff:ffff
1372ec2:8800::/242ec2:88ff:ffff:ffff:ffff:ffff:ffff:ffff
1382ec2:8900::/242ec2:89ff:ffff:ffff:ffff:ffff:ffff:ffff
1392ec2:8a00::/242ec2:8aff:ffff:ffff:ffff:ffff:ffff:ffff
1402ec2:8b00::/242ec2:8bff:ffff:ffff:ffff:ffff:ffff:ffff
1412ec2:8c00::/242ec2:8cff:ffff:ffff:ffff:ffff:ffff:ffff
1422ec2:8d00::/242ec2:8dff:ffff:ffff:ffff:ffff:ffff:ffff
1432ec2:8e00::/242ec2:8eff:ffff:ffff:ffff:ffff:ffff:ffff
1442ec2:8f00::/242ec2:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1452ec2:9000::/242ec2:90ff:ffff:ffff:ffff:ffff:ffff:ffff
1462ec2:9100::/242ec2:91ff:ffff:ffff:ffff:ffff:ffff:ffff
1472ec2:9200::/242ec2:92ff:ffff:ffff:ffff:ffff:ffff:ffff
1482ec2:9300::/242ec2:93ff:ffff:ffff:ffff:ffff:ffff:ffff
1492ec2:9400::/242ec2:94ff:ffff:ffff:ffff:ffff:ffff:ffff
1502ec2:9500::/242ec2:95ff:ffff:ffff:ffff:ffff:ffff:ffff
1512ec2:9600::/242ec2:96ff:ffff:ffff:ffff:ffff:ffff:ffff
1522ec2:9700::/242ec2:97ff:ffff:ffff:ffff:ffff:ffff:ffff
1532ec2:9800::/242ec2:98ff:ffff:ffff:ffff:ffff:ffff:ffff
1542ec2:9900::/242ec2:99ff:ffff:ffff:ffff:ffff:ffff:ffff
1552ec2:9a00::/242ec2:9aff:ffff:ffff:ffff:ffff:ffff:ffff
1562ec2:9b00::/242ec2:9bff:ffff:ffff:ffff:ffff:ffff:ffff
1572ec2:9c00::/242ec2:9cff:ffff:ffff:ffff:ffff:ffff:ffff
1582ec2:9d00::/242ec2:9dff:ffff:ffff:ffff:ffff:ffff:ffff
1592ec2:9e00::/242ec2:9eff:ffff:ffff:ffff:ffff:ffff:ffff
1602ec2:9f00::/242ec2:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1612ec2:a000::/242ec2:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
1622ec2:a100::/242ec2:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
1632ec2:a200::/242ec2:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
1642ec2:a300::/242ec2:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
1652ec2:a400::/242ec2:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
1662ec2:a500::/242ec2:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
1672ec2:a600::/242ec2:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
1682ec2:a700::/242ec2:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
1692ec2:a800::/242ec2:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
1702ec2:a900::/242ec2:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
1712ec2:aa00::/242ec2:aaff:ffff:ffff:ffff:ffff:ffff:ffff
1722ec2:ab00::/242ec2:abff:ffff:ffff:ffff:ffff:ffff:ffff
1732ec2:ac00::/242ec2:acff:ffff:ffff:ffff:ffff:ffff:ffff
1742ec2:ad00::/242ec2:adff:ffff:ffff:ffff:ffff:ffff:ffff
1752ec2:ae00::/242ec2:aeff:ffff:ffff:ffff:ffff:ffff:ffff
1762ec2:af00::/242ec2:afff:ffff:ffff:ffff:ffff:ffff:ffff
1772ec2:b000::/242ec2:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
1782ec2:b100::/242ec2:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
1792ec2:b200::/242ec2:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
1802ec2:b300::/242ec2:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
1812ec2:b400::/242ec2:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
1822ec2:b500::/242ec2:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
1832ec2:b600::/242ec2:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
1842ec2:b700::/242ec2:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
1852ec2:b800::/242ec2:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
1862ec2:b900::/242ec2:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
1872ec2:ba00::/242ec2:baff:ffff:ffff:ffff:ffff:ffff:ffff
1882ec2:bb00::/242ec2:bbff:ffff:ffff:ffff:ffff:ffff:ffff
1892ec2:bc00::/242ec2:bcff:ffff:ffff:ffff:ffff:ffff:ffff
1902ec2:bd00::/242ec2:bdff:ffff:ffff:ffff:ffff:ffff:ffff
1912ec2:be00::/242ec2:beff:ffff:ffff:ffff:ffff:ffff:ffff
1922ec2:bf00::/242ec2:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1932ec2:c000::/242ec2:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
1942ec2:c100::/242ec2:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
1952ec2:c200::/242ec2:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
1962ec2:c300::/242ec2:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
1972ec2:c400::/242ec2:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
1982ec2:c500::/242ec2:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
1992ec2:c600::/242ec2:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
2002ec2:c700::/242ec2:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
2012ec2:c800::/242ec2:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
2022ec2:c900::/242ec2:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
2032ec2:ca00::/242ec2:caff:ffff:ffff:ffff:ffff:ffff:ffff
2042ec2:cb00::/242ec2:cbff:ffff:ffff:ffff:ffff:ffff:ffff
2052ec2:cc00::/242ec2:ccff:ffff:ffff:ffff:ffff:ffff:ffff
2062ec2:cd00::/242ec2:cdff:ffff:ffff:ffff:ffff:ffff:ffff
2072ec2:ce00::/242ec2:ceff:ffff:ffff:ffff:ffff:ffff:ffff
2082ec2:cf00::/242ec2:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2092ec2:d000::/242ec2:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
2102ec2:d100::/242ec2:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
2112ec2:d200::/242ec2:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
2122ec2:d300::/242ec2:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
2132ec2:d400::/242ec2:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
2142ec2:d500::/242ec2:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
2152ec2:d600::/242ec2:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
2162ec2:d700::/242ec2:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
2172ec2:d800::/242ec2:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
2182ec2:d900::/242ec2:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
2192ec2:da00::/242ec2:daff:ffff:ffff:ffff:ffff:ffff:ffff
2202ec2:db00::/242ec2:dbff:ffff:ffff:ffff:ffff:ffff:ffff
2212ec2:dc00::/242ec2:dcff:ffff:ffff:ffff:ffff:ffff:ffff
2222ec2:dd00::/242ec2:ddff:ffff:ffff:ffff:ffff:ffff:ffff
2232ec2:de00::/242ec2:deff:ffff:ffff:ffff:ffff:ffff:ffff
2242ec2:df00::/242ec2:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2252ec2:e000::/242ec2:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
2262ec2:e100::/242ec2:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
2272ec2:e200::/242ec2:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
2282ec2:e300::/242ec2:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
2292ec2:e400::/242ec2:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
2302ec2:e500::/242ec2:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
2312ec2:e600::/242ec2:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
2322ec2:e700::/242ec2:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
2332ec2:e800::/242ec2:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
2342ec2:e900::/242ec2:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
2352ec2:ea00::/242ec2:eaff:ffff:ffff:ffff:ffff:ffff:ffff
2362ec2:eb00::/242ec2:ebff:ffff:ffff:ffff:ffff:ffff:ffff
2372ec2:ec00::/242ec2:ecff:ffff:ffff:ffff:ffff:ffff:ffff
2382ec2:ed00::/242ec2:edff:ffff:ffff:ffff:ffff:ffff:ffff
2392ec2:ee00::/242ec2:eeff:ffff:ffff:ffff:ffff:ffff:ffff
2402ec2:ef00::/242ec2:efff:ffff:ffff:ffff:ffff:ffff:ffff
2412ec2:f000::/242ec2:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
2422ec2:f100::/242ec2:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
2432ec2:f200::/242ec2:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
2442ec2:f300::/242ec2:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
2452ec2:f400::/242ec2:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
2462ec2:f500::/242ec2:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
2472ec2:f600::/242ec2:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
2482ec2:f700::/242ec2:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
2492ec2:f800::/242ec2:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
2502ec2:f900::/242ec2:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
2512ec2:fa00::/242ec2:faff:ffff:ffff:ffff:ffff:ffff:ffff
2522ec2:fb00::/242ec2:fbff:ffff:ffff:ffff:ffff:ffff:ffff
2532ec2:fc00::/242ec2:fcff:ffff:ffff:ffff:ffff:ffff:ffff
2542ec2:fd00::/242ec2:fdff:ffff:ffff:ffff:ffff:ffff:ffff
2552ec2:fe00::/242ec2:feff:ffff:ffff:ffff:ffff:ffff:ffff
2562ec2:ff00::/242ec2: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.