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

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

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