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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
2ed5::/16
First address
2ed5::
Last address
2ed5: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
2ed5:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
5.d.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)

2ed5::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
12ed5::/242ed5:ff:ffff:ffff:ffff:ffff:ffff:ffff
22ed5:100::/242ed5:1ff:ffff:ffff:ffff:ffff:ffff:ffff
32ed5:200::/242ed5:2ff:ffff:ffff:ffff:ffff:ffff:ffff
42ed5:300::/242ed5:3ff:ffff:ffff:ffff:ffff:ffff:ffff
52ed5:400::/242ed5:4ff:ffff:ffff:ffff:ffff:ffff:ffff
62ed5:500::/242ed5:5ff:ffff:ffff:ffff:ffff:ffff:ffff
72ed5:600::/242ed5:6ff:ffff:ffff:ffff:ffff:ffff:ffff
82ed5:700::/242ed5:7ff:ffff:ffff:ffff:ffff:ffff:ffff
92ed5:800::/242ed5:8ff:ffff:ffff:ffff:ffff:ffff:ffff
102ed5:900::/242ed5:9ff:ffff:ffff:ffff:ffff:ffff:ffff
112ed5:a00::/242ed5:aff:ffff:ffff:ffff:ffff:ffff:ffff
122ed5:b00::/242ed5:bff:ffff:ffff:ffff:ffff:ffff:ffff
132ed5:c00::/242ed5:cff:ffff:ffff:ffff:ffff:ffff:ffff
142ed5:d00::/242ed5:dff:ffff:ffff:ffff:ffff:ffff:ffff
152ed5:e00::/242ed5:eff:ffff:ffff:ffff:ffff:ffff:ffff
162ed5:f00::/242ed5:fff:ffff:ffff:ffff:ffff:ffff:ffff
172ed5:1000::/242ed5:10ff:ffff:ffff:ffff:ffff:ffff:ffff
182ed5:1100::/242ed5:11ff:ffff:ffff:ffff:ffff:ffff:ffff
192ed5:1200::/242ed5:12ff:ffff:ffff:ffff:ffff:ffff:ffff
202ed5:1300::/242ed5:13ff:ffff:ffff:ffff:ffff:ffff:ffff
212ed5:1400::/242ed5:14ff:ffff:ffff:ffff:ffff:ffff:ffff
222ed5:1500::/242ed5:15ff:ffff:ffff:ffff:ffff:ffff:ffff
232ed5:1600::/242ed5:16ff:ffff:ffff:ffff:ffff:ffff:ffff
242ed5:1700::/242ed5:17ff:ffff:ffff:ffff:ffff:ffff:ffff
252ed5:1800::/242ed5:18ff:ffff:ffff:ffff:ffff:ffff:ffff
262ed5:1900::/242ed5:19ff:ffff:ffff:ffff:ffff:ffff:ffff
272ed5:1a00::/242ed5:1aff:ffff:ffff:ffff:ffff:ffff:ffff
282ed5:1b00::/242ed5:1bff:ffff:ffff:ffff:ffff:ffff:ffff
292ed5:1c00::/242ed5:1cff:ffff:ffff:ffff:ffff:ffff:ffff
302ed5:1d00::/242ed5:1dff:ffff:ffff:ffff:ffff:ffff:ffff
312ed5:1e00::/242ed5:1eff:ffff:ffff:ffff:ffff:ffff:ffff
322ed5:1f00::/242ed5:1fff:ffff:ffff:ffff:ffff:ffff:ffff
332ed5:2000::/242ed5:20ff:ffff:ffff:ffff:ffff:ffff:ffff
342ed5:2100::/242ed5:21ff:ffff:ffff:ffff:ffff:ffff:ffff
352ed5:2200::/242ed5:22ff:ffff:ffff:ffff:ffff:ffff:ffff
362ed5:2300::/242ed5:23ff:ffff:ffff:ffff:ffff:ffff:ffff
372ed5:2400::/242ed5:24ff:ffff:ffff:ffff:ffff:ffff:ffff
382ed5:2500::/242ed5:25ff:ffff:ffff:ffff:ffff:ffff:ffff
392ed5:2600::/242ed5:26ff:ffff:ffff:ffff:ffff:ffff:ffff
402ed5:2700::/242ed5:27ff:ffff:ffff:ffff:ffff:ffff:ffff
412ed5:2800::/242ed5:28ff:ffff:ffff:ffff:ffff:ffff:ffff
422ed5:2900::/242ed5:29ff:ffff:ffff:ffff:ffff:ffff:ffff
432ed5:2a00::/242ed5:2aff:ffff:ffff:ffff:ffff:ffff:ffff
442ed5:2b00::/242ed5:2bff:ffff:ffff:ffff:ffff:ffff:ffff
452ed5:2c00::/242ed5:2cff:ffff:ffff:ffff:ffff:ffff:ffff
462ed5:2d00::/242ed5:2dff:ffff:ffff:ffff:ffff:ffff:ffff
472ed5:2e00::/242ed5:2eff:ffff:ffff:ffff:ffff:ffff:ffff
482ed5:2f00::/242ed5:2fff:ffff:ffff:ffff:ffff:ffff:ffff
492ed5:3000::/242ed5:30ff:ffff:ffff:ffff:ffff:ffff:ffff
502ed5:3100::/242ed5:31ff:ffff:ffff:ffff:ffff:ffff:ffff
512ed5:3200::/242ed5:32ff:ffff:ffff:ffff:ffff:ffff:ffff
522ed5:3300::/242ed5:33ff:ffff:ffff:ffff:ffff:ffff:ffff
532ed5:3400::/242ed5:34ff:ffff:ffff:ffff:ffff:ffff:ffff
542ed5:3500::/242ed5:35ff:ffff:ffff:ffff:ffff:ffff:ffff
552ed5:3600::/242ed5:36ff:ffff:ffff:ffff:ffff:ffff:ffff
562ed5:3700::/242ed5:37ff:ffff:ffff:ffff:ffff:ffff:ffff
572ed5:3800::/242ed5:38ff:ffff:ffff:ffff:ffff:ffff:ffff
582ed5:3900::/242ed5:39ff:ffff:ffff:ffff:ffff:ffff:ffff
592ed5:3a00::/242ed5:3aff:ffff:ffff:ffff:ffff:ffff:ffff
602ed5:3b00::/242ed5:3bff:ffff:ffff:ffff:ffff:ffff:ffff
612ed5:3c00::/242ed5:3cff:ffff:ffff:ffff:ffff:ffff:ffff
622ed5:3d00::/242ed5:3dff:ffff:ffff:ffff:ffff:ffff:ffff
632ed5:3e00::/242ed5:3eff:ffff:ffff:ffff:ffff:ffff:ffff
642ed5:3f00::/242ed5:3fff:ffff:ffff:ffff:ffff:ffff:ffff
652ed5:4000::/242ed5:40ff:ffff:ffff:ffff:ffff:ffff:ffff
662ed5:4100::/242ed5:41ff:ffff:ffff:ffff:ffff:ffff:ffff
672ed5:4200::/242ed5:42ff:ffff:ffff:ffff:ffff:ffff:ffff
682ed5:4300::/242ed5:43ff:ffff:ffff:ffff:ffff:ffff:ffff
692ed5:4400::/242ed5:44ff:ffff:ffff:ffff:ffff:ffff:ffff
702ed5:4500::/242ed5:45ff:ffff:ffff:ffff:ffff:ffff:ffff
712ed5:4600::/242ed5:46ff:ffff:ffff:ffff:ffff:ffff:ffff
722ed5:4700::/242ed5:47ff:ffff:ffff:ffff:ffff:ffff:ffff
732ed5:4800::/242ed5:48ff:ffff:ffff:ffff:ffff:ffff:ffff
742ed5:4900::/242ed5:49ff:ffff:ffff:ffff:ffff:ffff:ffff
752ed5:4a00::/242ed5:4aff:ffff:ffff:ffff:ffff:ffff:ffff
762ed5:4b00::/242ed5:4bff:ffff:ffff:ffff:ffff:ffff:ffff
772ed5:4c00::/242ed5:4cff:ffff:ffff:ffff:ffff:ffff:ffff
782ed5:4d00::/242ed5:4dff:ffff:ffff:ffff:ffff:ffff:ffff
792ed5:4e00::/242ed5:4eff:ffff:ffff:ffff:ffff:ffff:ffff
802ed5:4f00::/242ed5:4fff:ffff:ffff:ffff:ffff:ffff:ffff
812ed5:5000::/242ed5:50ff:ffff:ffff:ffff:ffff:ffff:ffff
822ed5:5100::/242ed5:51ff:ffff:ffff:ffff:ffff:ffff:ffff
832ed5:5200::/242ed5:52ff:ffff:ffff:ffff:ffff:ffff:ffff
842ed5:5300::/242ed5:53ff:ffff:ffff:ffff:ffff:ffff:ffff
852ed5:5400::/242ed5:54ff:ffff:ffff:ffff:ffff:ffff:ffff
862ed5:5500::/242ed5:55ff:ffff:ffff:ffff:ffff:ffff:ffff
872ed5:5600::/242ed5:56ff:ffff:ffff:ffff:ffff:ffff:ffff
882ed5:5700::/242ed5:57ff:ffff:ffff:ffff:ffff:ffff:ffff
892ed5:5800::/242ed5:58ff:ffff:ffff:ffff:ffff:ffff:ffff
902ed5:5900::/242ed5:59ff:ffff:ffff:ffff:ffff:ffff:ffff
912ed5:5a00::/242ed5:5aff:ffff:ffff:ffff:ffff:ffff:ffff
922ed5:5b00::/242ed5:5bff:ffff:ffff:ffff:ffff:ffff:ffff
932ed5:5c00::/242ed5:5cff:ffff:ffff:ffff:ffff:ffff:ffff
942ed5:5d00::/242ed5:5dff:ffff:ffff:ffff:ffff:ffff:ffff
952ed5:5e00::/242ed5:5eff:ffff:ffff:ffff:ffff:ffff:ffff
962ed5:5f00::/242ed5:5fff:ffff:ffff:ffff:ffff:ffff:ffff
972ed5:6000::/242ed5:60ff:ffff:ffff:ffff:ffff:ffff:ffff
982ed5:6100::/242ed5:61ff:ffff:ffff:ffff:ffff:ffff:ffff
992ed5:6200::/242ed5:62ff:ffff:ffff:ffff:ffff:ffff:ffff
1002ed5:6300::/242ed5:63ff:ffff:ffff:ffff:ffff:ffff:ffff
1012ed5:6400::/242ed5:64ff:ffff:ffff:ffff:ffff:ffff:ffff
1022ed5:6500::/242ed5:65ff:ffff:ffff:ffff:ffff:ffff:ffff
1032ed5:6600::/242ed5:66ff:ffff:ffff:ffff:ffff:ffff:ffff
1042ed5:6700::/242ed5:67ff:ffff:ffff:ffff:ffff:ffff:ffff
1052ed5:6800::/242ed5:68ff:ffff:ffff:ffff:ffff:ffff:ffff
1062ed5:6900::/242ed5:69ff:ffff:ffff:ffff:ffff:ffff:ffff
1072ed5:6a00::/242ed5:6aff:ffff:ffff:ffff:ffff:ffff:ffff
1082ed5:6b00::/242ed5:6bff:ffff:ffff:ffff:ffff:ffff:ffff
1092ed5:6c00::/242ed5:6cff:ffff:ffff:ffff:ffff:ffff:ffff
1102ed5:6d00::/242ed5:6dff:ffff:ffff:ffff:ffff:ffff:ffff
1112ed5:6e00::/242ed5:6eff:ffff:ffff:ffff:ffff:ffff:ffff
1122ed5:6f00::/242ed5:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1132ed5:7000::/242ed5:70ff:ffff:ffff:ffff:ffff:ffff:ffff
1142ed5:7100::/242ed5:71ff:ffff:ffff:ffff:ffff:ffff:ffff
1152ed5:7200::/242ed5:72ff:ffff:ffff:ffff:ffff:ffff:ffff
1162ed5:7300::/242ed5:73ff:ffff:ffff:ffff:ffff:ffff:ffff
1172ed5:7400::/242ed5:74ff:ffff:ffff:ffff:ffff:ffff:ffff
1182ed5:7500::/242ed5:75ff:ffff:ffff:ffff:ffff:ffff:ffff
1192ed5:7600::/242ed5:76ff:ffff:ffff:ffff:ffff:ffff:ffff
1202ed5:7700::/242ed5:77ff:ffff:ffff:ffff:ffff:ffff:ffff
1212ed5:7800::/242ed5:78ff:ffff:ffff:ffff:ffff:ffff:ffff
1222ed5:7900::/242ed5:79ff:ffff:ffff:ffff:ffff:ffff:ffff
1232ed5:7a00::/242ed5:7aff:ffff:ffff:ffff:ffff:ffff:ffff
1242ed5:7b00::/242ed5:7bff:ffff:ffff:ffff:ffff:ffff:ffff
1252ed5:7c00::/242ed5:7cff:ffff:ffff:ffff:ffff:ffff:ffff
1262ed5:7d00::/242ed5:7dff:ffff:ffff:ffff:ffff:ffff:ffff
1272ed5:7e00::/242ed5:7eff:ffff:ffff:ffff:ffff:ffff:ffff
1282ed5:7f00::/242ed5:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1292ed5:8000::/242ed5:80ff:ffff:ffff:ffff:ffff:ffff:ffff
1302ed5:8100::/242ed5:81ff:ffff:ffff:ffff:ffff:ffff:ffff
1312ed5:8200::/242ed5:82ff:ffff:ffff:ffff:ffff:ffff:ffff
1322ed5:8300::/242ed5:83ff:ffff:ffff:ffff:ffff:ffff:ffff
1332ed5:8400::/242ed5:84ff:ffff:ffff:ffff:ffff:ffff:ffff
1342ed5:8500::/242ed5:85ff:ffff:ffff:ffff:ffff:ffff:ffff
1352ed5:8600::/242ed5:86ff:ffff:ffff:ffff:ffff:ffff:ffff
1362ed5:8700::/242ed5:87ff:ffff:ffff:ffff:ffff:ffff:ffff
1372ed5:8800::/242ed5:88ff:ffff:ffff:ffff:ffff:ffff:ffff
1382ed5:8900::/242ed5:89ff:ffff:ffff:ffff:ffff:ffff:ffff
1392ed5:8a00::/242ed5:8aff:ffff:ffff:ffff:ffff:ffff:ffff
1402ed5:8b00::/242ed5:8bff:ffff:ffff:ffff:ffff:ffff:ffff
1412ed5:8c00::/242ed5:8cff:ffff:ffff:ffff:ffff:ffff:ffff
1422ed5:8d00::/242ed5:8dff:ffff:ffff:ffff:ffff:ffff:ffff
1432ed5:8e00::/242ed5:8eff:ffff:ffff:ffff:ffff:ffff:ffff
1442ed5:8f00::/242ed5:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1452ed5:9000::/242ed5:90ff:ffff:ffff:ffff:ffff:ffff:ffff
1462ed5:9100::/242ed5:91ff:ffff:ffff:ffff:ffff:ffff:ffff
1472ed5:9200::/242ed5:92ff:ffff:ffff:ffff:ffff:ffff:ffff
1482ed5:9300::/242ed5:93ff:ffff:ffff:ffff:ffff:ffff:ffff
1492ed5:9400::/242ed5:94ff:ffff:ffff:ffff:ffff:ffff:ffff
1502ed5:9500::/242ed5:95ff:ffff:ffff:ffff:ffff:ffff:ffff
1512ed5:9600::/242ed5:96ff:ffff:ffff:ffff:ffff:ffff:ffff
1522ed5:9700::/242ed5:97ff:ffff:ffff:ffff:ffff:ffff:ffff
1532ed5:9800::/242ed5:98ff:ffff:ffff:ffff:ffff:ffff:ffff
1542ed5:9900::/242ed5:99ff:ffff:ffff:ffff:ffff:ffff:ffff
1552ed5:9a00::/242ed5:9aff:ffff:ffff:ffff:ffff:ffff:ffff
1562ed5:9b00::/242ed5:9bff:ffff:ffff:ffff:ffff:ffff:ffff
1572ed5:9c00::/242ed5:9cff:ffff:ffff:ffff:ffff:ffff:ffff
1582ed5:9d00::/242ed5:9dff:ffff:ffff:ffff:ffff:ffff:ffff
1592ed5:9e00::/242ed5:9eff:ffff:ffff:ffff:ffff:ffff:ffff
1602ed5:9f00::/242ed5:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1612ed5:a000::/242ed5:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
1622ed5:a100::/242ed5:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
1632ed5:a200::/242ed5:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
1642ed5:a300::/242ed5:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
1652ed5:a400::/242ed5:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
1662ed5:a500::/242ed5:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
1672ed5:a600::/242ed5:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
1682ed5:a700::/242ed5:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
1692ed5:a800::/242ed5:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
1702ed5:a900::/242ed5:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
1712ed5:aa00::/242ed5:aaff:ffff:ffff:ffff:ffff:ffff:ffff
1722ed5:ab00::/242ed5:abff:ffff:ffff:ffff:ffff:ffff:ffff
1732ed5:ac00::/242ed5:acff:ffff:ffff:ffff:ffff:ffff:ffff
1742ed5:ad00::/242ed5:adff:ffff:ffff:ffff:ffff:ffff:ffff
1752ed5:ae00::/242ed5:aeff:ffff:ffff:ffff:ffff:ffff:ffff
1762ed5:af00::/242ed5:afff:ffff:ffff:ffff:ffff:ffff:ffff
1772ed5:b000::/242ed5:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
1782ed5:b100::/242ed5:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
1792ed5:b200::/242ed5:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
1802ed5:b300::/242ed5:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
1812ed5:b400::/242ed5:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
1822ed5:b500::/242ed5:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
1832ed5:b600::/242ed5:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
1842ed5:b700::/242ed5:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
1852ed5:b800::/242ed5:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
1862ed5:b900::/242ed5:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
1872ed5:ba00::/242ed5:baff:ffff:ffff:ffff:ffff:ffff:ffff
1882ed5:bb00::/242ed5:bbff:ffff:ffff:ffff:ffff:ffff:ffff
1892ed5:bc00::/242ed5:bcff:ffff:ffff:ffff:ffff:ffff:ffff
1902ed5:bd00::/242ed5:bdff:ffff:ffff:ffff:ffff:ffff:ffff
1912ed5:be00::/242ed5:beff:ffff:ffff:ffff:ffff:ffff:ffff
1922ed5:bf00::/242ed5:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1932ed5:c000::/242ed5:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
1942ed5:c100::/242ed5:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
1952ed5:c200::/242ed5:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
1962ed5:c300::/242ed5:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
1972ed5:c400::/242ed5:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
1982ed5:c500::/242ed5:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
1992ed5:c600::/242ed5:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
2002ed5:c700::/242ed5:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
2012ed5:c800::/242ed5:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
2022ed5:c900::/242ed5:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
2032ed5:ca00::/242ed5:caff:ffff:ffff:ffff:ffff:ffff:ffff
2042ed5:cb00::/242ed5:cbff:ffff:ffff:ffff:ffff:ffff:ffff
2052ed5:cc00::/242ed5:ccff:ffff:ffff:ffff:ffff:ffff:ffff
2062ed5:cd00::/242ed5:cdff:ffff:ffff:ffff:ffff:ffff:ffff
2072ed5:ce00::/242ed5:ceff:ffff:ffff:ffff:ffff:ffff:ffff
2082ed5:cf00::/242ed5:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2092ed5:d000::/242ed5:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
2102ed5:d100::/242ed5:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
2112ed5:d200::/242ed5:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
2122ed5:d300::/242ed5:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
2132ed5:d400::/242ed5:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
2142ed5:d500::/242ed5:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
2152ed5:d600::/242ed5:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
2162ed5:d700::/242ed5:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
2172ed5:d800::/242ed5:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
2182ed5:d900::/242ed5:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
2192ed5:da00::/242ed5:daff:ffff:ffff:ffff:ffff:ffff:ffff
2202ed5:db00::/242ed5:dbff:ffff:ffff:ffff:ffff:ffff:ffff
2212ed5:dc00::/242ed5:dcff:ffff:ffff:ffff:ffff:ffff:ffff
2222ed5:dd00::/242ed5:ddff:ffff:ffff:ffff:ffff:ffff:ffff
2232ed5:de00::/242ed5:deff:ffff:ffff:ffff:ffff:ffff:ffff
2242ed5:df00::/242ed5:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2252ed5:e000::/242ed5:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
2262ed5:e100::/242ed5:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
2272ed5:e200::/242ed5:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
2282ed5:e300::/242ed5:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
2292ed5:e400::/242ed5:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
2302ed5:e500::/242ed5:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
2312ed5:e600::/242ed5:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
2322ed5:e700::/242ed5:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
2332ed5:e800::/242ed5:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
2342ed5:e900::/242ed5:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
2352ed5:ea00::/242ed5:eaff:ffff:ffff:ffff:ffff:ffff:ffff
2362ed5:eb00::/242ed5:ebff:ffff:ffff:ffff:ffff:ffff:ffff
2372ed5:ec00::/242ed5:ecff:ffff:ffff:ffff:ffff:ffff:ffff
2382ed5:ed00::/242ed5:edff:ffff:ffff:ffff:ffff:ffff:ffff
2392ed5:ee00::/242ed5:eeff:ffff:ffff:ffff:ffff:ffff:ffff
2402ed5:ef00::/242ed5:efff:ffff:ffff:ffff:ffff:ffff:ffff
2412ed5:f000::/242ed5:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
2422ed5:f100::/242ed5:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
2432ed5:f200::/242ed5:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
2442ed5:f300::/242ed5:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
2452ed5:f400::/242ed5:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
2462ed5:f500::/242ed5:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
2472ed5:f600::/242ed5:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
2482ed5:f700::/242ed5:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
2492ed5:f800::/242ed5:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
2502ed5:f900::/242ed5:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
2512ed5:fa00::/242ed5:faff:ffff:ffff:ffff:ffff:ffff:ffff
2522ed5:fb00::/242ed5:fbff:ffff:ffff:ffff:ffff:ffff:ffff
2532ed5:fc00::/242ed5:fcff:ffff:ffff:ffff:ffff:ffff:ffff
2542ed5:fd00::/242ed5:fdff:ffff:ffff:ffff:ffff:ffff:ffff
2552ed5:fe00::/242ed5:feff:ffff:ffff:ffff:ffff:ffff:ffff
2562ed5:ff00::/242ed5: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.