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Speed and call quality testTest delay, jitter and speed, with a focus on phone calls.My IP addressYour public IPv4 and IPv6 addresses, provider and address range.WhoIs lookupWho owns a domain or IP address, when it expires, and its DNS.DNS reportEvery DNS record for a domain, with email setup checked.IP subnet calculatorWork out a network's range, mask and hosts, and split it into subnets.

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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
2e2e::/16
First address
2e2e::
Last address
2e2e: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
2e2e:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
e.2.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)

2e2e::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
12e2e::/242e2e:ff:ffff:ffff:ffff:ffff:ffff:ffff
22e2e:100::/242e2e:1ff:ffff:ffff:ffff:ffff:ffff:ffff
32e2e:200::/242e2e:2ff:ffff:ffff:ffff:ffff:ffff:ffff
42e2e:300::/242e2e:3ff:ffff:ffff:ffff:ffff:ffff:ffff
52e2e:400::/242e2e:4ff:ffff:ffff:ffff:ffff:ffff:ffff
62e2e:500::/242e2e:5ff:ffff:ffff:ffff:ffff:ffff:ffff
72e2e:600::/242e2e:6ff:ffff:ffff:ffff:ffff:ffff:ffff
82e2e:700::/242e2e:7ff:ffff:ffff:ffff:ffff:ffff:ffff
92e2e:800::/242e2e:8ff:ffff:ffff:ffff:ffff:ffff:ffff
102e2e:900::/242e2e:9ff:ffff:ffff:ffff:ffff:ffff:ffff
112e2e:a00::/242e2e:aff:ffff:ffff:ffff:ffff:ffff:ffff
122e2e:b00::/242e2e:bff:ffff:ffff:ffff:ffff:ffff:ffff
132e2e:c00::/242e2e:cff:ffff:ffff:ffff:ffff:ffff:ffff
142e2e:d00::/242e2e:dff:ffff:ffff:ffff:ffff:ffff:ffff
152e2e:e00::/242e2e:eff:ffff:ffff:ffff:ffff:ffff:ffff
162e2e:f00::/242e2e:fff:ffff:ffff:ffff:ffff:ffff:ffff
172e2e:1000::/242e2e:10ff:ffff:ffff:ffff:ffff:ffff:ffff
182e2e:1100::/242e2e:11ff:ffff:ffff:ffff:ffff:ffff:ffff
192e2e:1200::/242e2e:12ff:ffff:ffff:ffff:ffff:ffff:ffff
202e2e:1300::/242e2e:13ff:ffff:ffff:ffff:ffff:ffff:ffff
212e2e:1400::/242e2e:14ff:ffff:ffff:ffff:ffff:ffff:ffff
222e2e:1500::/242e2e:15ff:ffff:ffff:ffff:ffff:ffff:ffff
232e2e:1600::/242e2e:16ff:ffff:ffff:ffff:ffff:ffff:ffff
242e2e:1700::/242e2e:17ff:ffff:ffff:ffff:ffff:ffff:ffff
252e2e:1800::/242e2e:18ff:ffff:ffff:ffff:ffff:ffff:ffff
262e2e:1900::/242e2e:19ff:ffff:ffff:ffff:ffff:ffff:ffff
272e2e:1a00::/242e2e:1aff:ffff:ffff:ffff:ffff:ffff:ffff
282e2e:1b00::/242e2e:1bff:ffff:ffff:ffff:ffff:ffff:ffff
292e2e:1c00::/242e2e:1cff:ffff:ffff:ffff:ffff:ffff:ffff
302e2e:1d00::/242e2e:1dff:ffff:ffff:ffff:ffff:ffff:ffff
312e2e:1e00::/242e2e:1eff:ffff:ffff:ffff:ffff:ffff:ffff
322e2e:1f00::/242e2e:1fff:ffff:ffff:ffff:ffff:ffff:ffff
332e2e:2000::/242e2e:20ff:ffff:ffff:ffff:ffff:ffff:ffff
342e2e:2100::/242e2e:21ff:ffff:ffff:ffff:ffff:ffff:ffff
352e2e:2200::/242e2e:22ff:ffff:ffff:ffff:ffff:ffff:ffff
362e2e:2300::/242e2e:23ff:ffff:ffff:ffff:ffff:ffff:ffff
372e2e:2400::/242e2e:24ff:ffff:ffff:ffff:ffff:ffff:ffff
382e2e:2500::/242e2e:25ff:ffff:ffff:ffff:ffff:ffff:ffff
392e2e:2600::/242e2e:26ff:ffff:ffff:ffff:ffff:ffff:ffff
402e2e:2700::/242e2e:27ff:ffff:ffff:ffff:ffff:ffff:ffff
412e2e:2800::/242e2e:28ff:ffff:ffff:ffff:ffff:ffff:ffff
422e2e:2900::/242e2e:29ff:ffff:ffff:ffff:ffff:ffff:ffff
432e2e:2a00::/242e2e:2aff:ffff:ffff:ffff:ffff:ffff:ffff
442e2e:2b00::/242e2e:2bff:ffff:ffff:ffff:ffff:ffff:ffff
452e2e:2c00::/242e2e:2cff:ffff:ffff:ffff:ffff:ffff:ffff
462e2e:2d00::/242e2e:2dff:ffff:ffff:ffff:ffff:ffff:ffff
472e2e:2e00::/242e2e:2eff:ffff:ffff:ffff:ffff:ffff:ffff
482e2e:2f00::/242e2e:2fff:ffff:ffff:ffff:ffff:ffff:ffff
492e2e:3000::/242e2e:30ff:ffff:ffff:ffff:ffff:ffff:ffff
502e2e:3100::/242e2e:31ff:ffff:ffff:ffff:ffff:ffff:ffff
512e2e:3200::/242e2e:32ff:ffff:ffff:ffff:ffff:ffff:ffff
522e2e:3300::/242e2e:33ff:ffff:ffff:ffff:ffff:ffff:ffff
532e2e:3400::/242e2e:34ff:ffff:ffff:ffff:ffff:ffff:ffff
542e2e:3500::/242e2e:35ff:ffff:ffff:ffff:ffff:ffff:ffff
552e2e:3600::/242e2e:36ff:ffff:ffff:ffff:ffff:ffff:ffff
562e2e:3700::/242e2e:37ff:ffff:ffff:ffff:ffff:ffff:ffff
572e2e:3800::/242e2e:38ff:ffff:ffff:ffff:ffff:ffff:ffff
582e2e:3900::/242e2e:39ff:ffff:ffff:ffff:ffff:ffff:ffff
592e2e:3a00::/242e2e:3aff:ffff:ffff:ffff:ffff:ffff:ffff
602e2e:3b00::/242e2e:3bff:ffff:ffff:ffff:ffff:ffff:ffff
612e2e:3c00::/242e2e:3cff:ffff:ffff:ffff:ffff:ffff:ffff
622e2e:3d00::/242e2e:3dff:ffff:ffff:ffff:ffff:ffff:ffff
632e2e:3e00::/242e2e:3eff:ffff:ffff:ffff:ffff:ffff:ffff
642e2e:3f00::/242e2e:3fff:ffff:ffff:ffff:ffff:ffff:ffff
652e2e:4000::/242e2e:40ff:ffff:ffff:ffff:ffff:ffff:ffff
662e2e:4100::/242e2e:41ff:ffff:ffff:ffff:ffff:ffff:ffff
672e2e:4200::/242e2e:42ff:ffff:ffff:ffff:ffff:ffff:ffff
682e2e:4300::/242e2e:43ff:ffff:ffff:ffff:ffff:ffff:ffff
692e2e:4400::/242e2e:44ff:ffff:ffff:ffff:ffff:ffff:ffff
702e2e:4500::/242e2e:45ff:ffff:ffff:ffff:ffff:ffff:ffff
712e2e:4600::/242e2e:46ff:ffff:ffff:ffff:ffff:ffff:ffff
722e2e:4700::/242e2e:47ff:ffff:ffff:ffff:ffff:ffff:ffff
732e2e:4800::/242e2e:48ff:ffff:ffff:ffff:ffff:ffff:ffff
742e2e:4900::/242e2e:49ff:ffff:ffff:ffff:ffff:ffff:ffff
752e2e:4a00::/242e2e:4aff:ffff:ffff:ffff:ffff:ffff:ffff
762e2e:4b00::/242e2e:4bff:ffff:ffff:ffff:ffff:ffff:ffff
772e2e:4c00::/242e2e:4cff:ffff:ffff:ffff:ffff:ffff:ffff
782e2e:4d00::/242e2e:4dff:ffff:ffff:ffff:ffff:ffff:ffff
792e2e:4e00::/242e2e:4eff:ffff:ffff:ffff:ffff:ffff:ffff
802e2e:4f00::/242e2e:4fff:ffff:ffff:ffff:ffff:ffff:ffff
812e2e:5000::/242e2e:50ff:ffff:ffff:ffff:ffff:ffff:ffff
822e2e:5100::/242e2e:51ff:ffff:ffff:ffff:ffff:ffff:ffff
832e2e:5200::/242e2e:52ff:ffff:ffff:ffff:ffff:ffff:ffff
842e2e:5300::/242e2e:53ff:ffff:ffff:ffff:ffff:ffff:ffff
852e2e:5400::/242e2e:54ff:ffff:ffff:ffff:ffff:ffff:ffff
862e2e:5500::/242e2e:55ff:ffff:ffff:ffff:ffff:ffff:ffff
872e2e:5600::/242e2e:56ff:ffff:ffff:ffff:ffff:ffff:ffff
882e2e:5700::/242e2e:57ff:ffff:ffff:ffff:ffff:ffff:ffff
892e2e:5800::/242e2e:58ff:ffff:ffff:ffff:ffff:ffff:ffff
902e2e:5900::/242e2e:59ff:ffff:ffff:ffff:ffff:ffff:ffff
912e2e:5a00::/242e2e:5aff:ffff:ffff:ffff:ffff:ffff:ffff
922e2e:5b00::/242e2e:5bff:ffff:ffff:ffff:ffff:ffff:ffff
932e2e:5c00::/242e2e:5cff:ffff:ffff:ffff:ffff:ffff:ffff
942e2e:5d00::/242e2e:5dff:ffff:ffff:ffff:ffff:ffff:ffff
952e2e:5e00::/242e2e:5eff:ffff:ffff:ffff:ffff:ffff:ffff
962e2e:5f00::/242e2e:5fff:ffff:ffff:ffff:ffff:ffff:ffff
972e2e:6000::/242e2e:60ff:ffff:ffff:ffff:ffff:ffff:ffff
982e2e:6100::/242e2e:61ff:ffff:ffff:ffff:ffff:ffff:ffff
992e2e:6200::/242e2e:62ff:ffff:ffff:ffff:ffff:ffff:ffff
1002e2e:6300::/242e2e:63ff:ffff:ffff:ffff:ffff:ffff:ffff
1012e2e:6400::/242e2e:64ff:ffff:ffff:ffff:ffff:ffff:ffff
1022e2e:6500::/242e2e:65ff:ffff:ffff:ffff:ffff:ffff:ffff
1032e2e:6600::/242e2e:66ff:ffff:ffff:ffff:ffff:ffff:ffff
1042e2e:6700::/242e2e:67ff:ffff:ffff:ffff:ffff:ffff:ffff
1052e2e:6800::/242e2e:68ff:ffff:ffff:ffff:ffff:ffff:ffff
1062e2e:6900::/242e2e:69ff:ffff:ffff:ffff:ffff:ffff:ffff
1072e2e:6a00::/242e2e:6aff:ffff:ffff:ffff:ffff:ffff:ffff
1082e2e:6b00::/242e2e:6bff:ffff:ffff:ffff:ffff:ffff:ffff
1092e2e:6c00::/242e2e:6cff:ffff:ffff:ffff:ffff:ffff:ffff
1102e2e:6d00::/242e2e:6dff:ffff:ffff:ffff:ffff:ffff:ffff
1112e2e:6e00::/242e2e:6eff:ffff:ffff:ffff:ffff:ffff:ffff
1122e2e:6f00::/242e2e:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1132e2e:7000::/242e2e:70ff:ffff:ffff:ffff:ffff:ffff:ffff
1142e2e:7100::/242e2e:71ff:ffff:ffff:ffff:ffff:ffff:ffff
1152e2e:7200::/242e2e:72ff:ffff:ffff:ffff:ffff:ffff:ffff
1162e2e:7300::/242e2e:73ff:ffff:ffff:ffff:ffff:ffff:ffff
1172e2e:7400::/242e2e:74ff:ffff:ffff:ffff:ffff:ffff:ffff
1182e2e:7500::/242e2e:75ff:ffff:ffff:ffff:ffff:ffff:ffff
1192e2e:7600::/242e2e:76ff:ffff:ffff:ffff:ffff:ffff:ffff
1202e2e:7700::/242e2e:77ff:ffff:ffff:ffff:ffff:ffff:ffff
1212e2e:7800::/242e2e:78ff:ffff:ffff:ffff:ffff:ffff:ffff
1222e2e:7900::/242e2e:79ff:ffff:ffff:ffff:ffff:ffff:ffff
1232e2e:7a00::/242e2e:7aff:ffff:ffff:ffff:ffff:ffff:ffff
1242e2e:7b00::/242e2e:7bff:ffff:ffff:ffff:ffff:ffff:ffff
1252e2e:7c00::/242e2e:7cff:ffff:ffff:ffff:ffff:ffff:ffff
1262e2e:7d00::/242e2e:7dff:ffff:ffff:ffff:ffff:ffff:ffff
1272e2e:7e00::/242e2e:7eff:ffff:ffff:ffff:ffff:ffff:ffff
1282e2e:7f00::/242e2e:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1292e2e:8000::/242e2e:80ff:ffff:ffff:ffff:ffff:ffff:ffff
1302e2e:8100::/242e2e:81ff:ffff:ffff:ffff:ffff:ffff:ffff
1312e2e:8200::/242e2e:82ff:ffff:ffff:ffff:ffff:ffff:ffff
1322e2e:8300::/242e2e:83ff:ffff:ffff:ffff:ffff:ffff:ffff
1332e2e:8400::/242e2e:84ff:ffff:ffff:ffff:ffff:ffff:ffff
1342e2e:8500::/242e2e:85ff:ffff:ffff:ffff:ffff:ffff:ffff
1352e2e:8600::/242e2e:86ff:ffff:ffff:ffff:ffff:ffff:ffff
1362e2e:8700::/242e2e:87ff:ffff:ffff:ffff:ffff:ffff:ffff
1372e2e:8800::/242e2e:88ff:ffff:ffff:ffff:ffff:ffff:ffff
1382e2e:8900::/242e2e:89ff:ffff:ffff:ffff:ffff:ffff:ffff
1392e2e:8a00::/242e2e:8aff:ffff:ffff:ffff:ffff:ffff:ffff
1402e2e:8b00::/242e2e:8bff:ffff:ffff:ffff:ffff:ffff:ffff
1412e2e:8c00::/242e2e:8cff:ffff:ffff:ffff:ffff:ffff:ffff
1422e2e:8d00::/242e2e:8dff:ffff:ffff:ffff:ffff:ffff:ffff
1432e2e:8e00::/242e2e:8eff:ffff:ffff:ffff:ffff:ffff:ffff
1442e2e:8f00::/242e2e:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1452e2e:9000::/242e2e:90ff:ffff:ffff:ffff:ffff:ffff:ffff
1462e2e:9100::/242e2e:91ff:ffff:ffff:ffff:ffff:ffff:ffff
1472e2e:9200::/242e2e:92ff:ffff:ffff:ffff:ffff:ffff:ffff
1482e2e:9300::/242e2e:93ff:ffff:ffff:ffff:ffff:ffff:ffff
1492e2e:9400::/242e2e:94ff:ffff:ffff:ffff:ffff:ffff:ffff
1502e2e:9500::/242e2e:95ff:ffff:ffff:ffff:ffff:ffff:ffff
1512e2e:9600::/242e2e:96ff:ffff:ffff:ffff:ffff:ffff:ffff
1522e2e:9700::/242e2e:97ff:ffff:ffff:ffff:ffff:ffff:ffff
1532e2e:9800::/242e2e:98ff:ffff:ffff:ffff:ffff:ffff:ffff
1542e2e:9900::/242e2e:99ff:ffff:ffff:ffff:ffff:ffff:ffff
1552e2e:9a00::/242e2e:9aff:ffff:ffff:ffff:ffff:ffff:ffff
1562e2e:9b00::/242e2e:9bff:ffff:ffff:ffff:ffff:ffff:ffff
1572e2e:9c00::/242e2e:9cff:ffff:ffff:ffff:ffff:ffff:ffff
1582e2e:9d00::/242e2e:9dff:ffff:ffff:ffff:ffff:ffff:ffff
1592e2e:9e00::/242e2e:9eff:ffff:ffff:ffff:ffff:ffff:ffff
1602e2e:9f00::/242e2e:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1612e2e:a000::/242e2e:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
1622e2e:a100::/242e2e:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
1632e2e:a200::/242e2e:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
1642e2e:a300::/242e2e:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
1652e2e:a400::/242e2e:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
1662e2e:a500::/242e2e:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
1672e2e:a600::/242e2e:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
1682e2e:a700::/242e2e:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
1692e2e:a800::/242e2e:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
1702e2e:a900::/242e2e:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
1712e2e:aa00::/242e2e:aaff:ffff:ffff:ffff:ffff:ffff:ffff
1722e2e:ab00::/242e2e:abff:ffff:ffff:ffff:ffff:ffff:ffff
1732e2e:ac00::/242e2e:acff:ffff:ffff:ffff:ffff:ffff:ffff
1742e2e:ad00::/242e2e:adff:ffff:ffff:ffff:ffff:ffff:ffff
1752e2e:ae00::/242e2e:aeff:ffff:ffff:ffff:ffff:ffff:ffff
1762e2e:af00::/242e2e:afff:ffff:ffff:ffff:ffff:ffff:ffff
1772e2e:b000::/242e2e:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
1782e2e:b100::/242e2e:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
1792e2e:b200::/242e2e:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
1802e2e:b300::/242e2e:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
1812e2e:b400::/242e2e:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
1822e2e:b500::/242e2e:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
1832e2e:b600::/242e2e:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
1842e2e:b700::/242e2e:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
1852e2e:b800::/242e2e:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
1862e2e:b900::/242e2e:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
1872e2e:ba00::/242e2e:baff:ffff:ffff:ffff:ffff:ffff:ffff
1882e2e:bb00::/242e2e:bbff:ffff:ffff:ffff:ffff:ffff:ffff
1892e2e:bc00::/242e2e:bcff:ffff:ffff:ffff:ffff:ffff:ffff
1902e2e:bd00::/242e2e:bdff:ffff:ffff:ffff:ffff:ffff:ffff
1912e2e:be00::/242e2e:beff:ffff:ffff:ffff:ffff:ffff:ffff
1922e2e:bf00::/242e2e:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1932e2e:c000::/242e2e:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
1942e2e:c100::/242e2e:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
1952e2e:c200::/242e2e:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
1962e2e:c300::/242e2e:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
1972e2e:c400::/242e2e:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
1982e2e:c500::/242e2e:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
1992e2e:c600::/242e2e:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
2002e2e:c700::/242e2e:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
2012e2e:c800::/242e2e:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
2022e2e:c900::/242e2e:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
2032e2e:ca00::/242e2e:caff:ffff:ffff:ffff:ffff:ffff:ffff
2042e2e:cb00::/242e2e:cbff:ffff:ffff:ffff:ffff:ffff:ffff
2052e2e:cc00::/242e2e:ccff:ffff:ffff:ffff:ffff:ffff:ffff
2062e2e:cd00::/242e2e:cdff:ffff:ffff:ffff:ffff:ffff:ffff
2072e2e:ce00::/242e2e:ceff:ffff:ffff:ffff:ffff:ffff:ffff
2082e2e:cf00::/242e2e:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2092e2e:d000::/242e2e:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
2102e2e:d100::/242e2e:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
2112e2e:d200::/242e2e:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
2122e2e:d300::/242e2e:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
2132e2e:d400::/242e2e:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
2142e2e:d500::/242e2e:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
2152e2e:d600::/242e2e:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
2162e2e:d700::/242e2e:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
2172e2e:d800::/242e2e:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
2182e2e:d900::/242e2e:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
2192e2e:da00::/242e2e:daff:ffff:ffff:ffff:ffff:ffff:ffff
2202e2e:db00::/242e2e:dbff:ffff:ffff:ffff:ffff:ffff:ffff
2212e2e:dc00::/242e2e:dcff:ffff:ffff:ffff:ffff:ffff:ffff
2222e2e:dd00::/242e2e:ddff:ffff:ffff:ffff:ffff:ffff:ffff
2232e2e:de00::/242e2e:deff:ffff:ffff:ffff:ffff:ffff:ffff
2242e2e:df00::/242e2e:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2252e2e:e000::/242e2e:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
2262e2e:e100::/242e2e:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
2272e2e:e200::/242e2e:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
2282e2e:e300::/242e2e:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
2292e2e:e400::/242e2e:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
2302e2e:e500::/242e2e:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
2312e2e:e600::/242e2e:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
2322e2e:e700::/242e2e:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
2332e2e:e800::/242e2e:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
2342e2e:e900::/242e2e:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
2352e2e:ea00::/242e2e:eaff:ffff:ffff:ffff:ffff:ffff:ffff
2362e2e:eb00::/242e2e:ebff:ffff:ffff:ffff:ffff:ffff:ffff
2372e2e:ec00::/242e2e:ecff:ffff:ffff:ffff:ffff:ffff:ffff
2382e2e:ed00::/242e2e:edff:ffff:ffff:ffff:ffff:ffff:ffff
2392e2e:ee00::/242e2e:eeff:ffff:ffff:ffff:ffff:ffff:ffff
2402e2e:ef00::/242e2e:efff:ffff:ffff:ffff:ffff:ffff:ffff
2412e2e:f000::/242e2e:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
2422e2e:f100::/242e2e:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
2432e2e:f200::/242e2e:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
2442e2e:f300::/242e2e:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
2452e2e:f400::/242e2e:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
2462e2e:f500::/242e2e:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
2472e2e:f600::/242e2e:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
2482e2e:f700::/242e2e:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
2492e2e:f800::/242e2e:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
2502e2e:f900::/242e2e:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
2512e2e:fa00::/242e2e:faff:ffff:ffff:ffff:ffff:ffff:ffff
2522e2e:fb00::/242e2e:fbff:ffff:ffff:ffff:ffff:ffff:ffff
2532e2e:fc00::/242e2e:fcff:ffff:ffff:ffff:ffff:ffff:ffff
2542e2e:fd00::/242e2e:fdff:ffff:ffff:ffff:ffff:ffff:ffff
2552e2e:fe00::/242e2e:feff:ffff:ffff:ffff:ffff:ffff:ffff
2562e2e:ff00::/242e2e: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.