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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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Update checkIs this computer, phone and browser up to date? With links to update.Camera and mic testCheck your webcam and microphone before a call.Test print pagePrint an A4 page to check a printer: edges, text, line art and colours.

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Surftec

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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
2e2d::/16
First address
2e2d::
Last address
2e2d: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
2e2d:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
d.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)

2e2d::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
12e2d::/242e2d:ff:ffff:ffff:ffff:ffff:ffff:ffff
22e2d:100::/242e2d:1ff:ffff:ffff:ffff:ffff:ffff:ffff
32e2d:200::/242e2d:2ff:ffff:ffff:ffff:ffff:ffff:ffff
42e2d:300::/242e2d:3ff:ffff:ffff:ffff:ffff:ffff:ffff
52e2d:400::/242e2d:4ff:ffff:ffff:ffff:ffff:ffff:ffff
62e2d:500::/242e2d:5ff:ffff:ffff:ffff:ffff:ffff:ffff
72e2d:600::/242e2d:6ff:ffff:ffff:ffff:ffff:ffff:ffff
82e2d:700::/242e2d:7ff:ffff:ffff:ffff:ffff:ffff:ffff
92e2d:800::/242e2d:8ff:ffff:ffff:ffff:ffff:ffff:ffff
102e2d:900::/242e2d:9ff:ffff:ffff:ffff:ffff:ffff:ffff
112e2d:a00::/242e2d:aff:ffff:ffff:ffff:ffff:ffff:ffff
122e2d:b00::/242e2d:bff:ffff:ffff:ffff:ffff:ffff:ffff
132e2d:c00::/242e2d:cff:ffff:ffff:ffff:ffff:ffff:ffff
142e2d:d00::/242e2d:dff:ffff:ffff:ffff:ffff:ffff:ffff
152e2d:e00::/242e2d:eff:ffff:ffff:ffff:ffff:ffff:ffff
162e2d:f00::/242e2d:fff:ffff:ffff:ffff:ffff:ffff:ffff
172e2d:1000::/242e2d:10ff:ffff:ffff:ffff:ffff:ffff:ffff
182e2d:1100::/242e2d:11ff:ffff:ffff:ffff:ffff:ffff:ffff
192e2d:1200::/242e2d:12ff:ffff:ffff:ffff:ffff:ffff:ffff
202e2d:1300::/242e2d:13ff:ffff:ffff:ffff:ffff:ffff:ffff
212e2d:1400::/242e2d:14ff:ffff:ffff:ffff:ffff:ffff:ffff
222e2d:1500::/242e2d:15ff:ffff:ffff:ffff:ffff:ffff:ffff
232e2d:1600::/242e2d:16ff:ffff:ffff:ffff:ffff:ffff:ffff
242e2d:1700::/242e2d:17ff:ffff:ffff:ffff:ffff:ffff:ffff
252e2d:1800::/242e2d:18ff:ffff:ffff:ffff:ffff:ffff:ffff
262e2d:1900::/242e2d:19ff:ffff:ffff:ffff:ffff:ffff:ffff
272e2d:1a00::/242e2d:1aff:ffff:ffff:ffff:ffff:ffff:ffff
282e2d:1b00::/242e2d:1bff:ffff:ffff:ffff:ffff:ffff:ffff
292e2d:1c00::/242e2d:1cff:ffff:ffff:ffff:ffff:ffff:ffff
302e2d:1d00::/242e2d:1dff:ffff:ffff:ffff:ffff:ffff:ffff
312e2d:1e00::/242e2d:1eff:ffff:ffff:ffff:ffff:ffff:ffff
322e2d:1f00::/242e2d:1fff:ffff:ffff:ffff:ffff:ffff:ffff
332e2d:2000::/242e2d:20ff:ffff:ffff:ffff:ffff:ffff:ffff
342e2d:2100::/242e2d:21ff:ffff:ffff:ffff:ffff:ffff:ffff
352e2d:2200::/242e2d:22ff:ffff:ffff:ffff:ffff:ffff:ffff
362e2d:2300::/242e2d:23ff:ffff:ffff:ffff:ffff:ffff:ffff
372e2d:2400::/242e2d:24ff:ffff:ffff:ffff:ffff:ffff:ffff
382e2d:2500::/242e2d:25ff:ffff:ffff:ffff:ffff:ffff:ffff
392e2d:2600::/242e2d:26ff:ffff:ffff:ffff:ffff:ffff:ffff
402e2d:2700::/242e2d:27ff:ffff:ffff:ffff:ffff:ffff:ffff
412e2d:2800::/242e2d:28ff:ffff:ffff:ffff:ffff:ffff:ffff
422e2d:2900::/242e2d:29ff:ffff:ffff:ffff:ffff:ffff:ffff
432e2d:2a00::/242e2d:2aff:ffff:ffff:ffff:ffff:ffff:ffff
442e2d:2b00::/242e2d:2bff:ffff:ffff:ffff:ffff:ffff:ffff
452e2d:2c00::/242e2d:2cff:ffff:ffff:ffff:ffff:ffff:ffff
462e2d:2d00::/242e2d:2dff:ffff:ffff:ffff:ffff:ffff:ffff
472e2d:2e00::/242e2d:2eff:ffff:ffff:ffff:ffff:ffff:ffff
482e2d:2f00::/242e2d:2fff:ffff:ffff:ffff:ffff:ffff:ffff
492e2d:3000::/242e2d:30ff:ffff:ffff:ffff:ffff:ffff:ffff
502e2d:3100::/242e2d:31ff:ffff:ffff:ffff:ffff:ffff:ffff
512e2d:3200::/242e2d:32ff:ffff:ffff:ffff:ffff:ffff:ffff
522e2d:3300::/242e2d:33ff:ffff:ffff:ffff:ffff:ffff:ffff
532e2d:3400::/242e2d:34ff:ffff:ffff:ffff:ffff:ffff:ffff
542e2d:3500::/242e2d:35ff:ffff:ffff:ffff:ffff:ffff:ffff
552e2d:3600::/242e2d:36ff:ffff:ffff:ffff:ffff:ffff:ffff
562e2d:3700::/242e2d:37ff:ffff:ffff:ffff:ffff:ffff:ffff
572e2d:3800::/242e2d:38ff:ffff:ffff:ffff:ffff:ffff:ffff
582e2d:3900::/242e2d:39ff:ffff:ffff:ffff:ffff:ffff:ffff
592e2d:3a00::/242e2d:3aff:ffff:ffff:ffff:ffff:ffff:ffff
602e2d:3b00::/242e2d:3bff:ffff:ffff:ffff:ffff:ffff:ffff
612e2d:3c00::/242e2d:3cff:ffff:ffff:ffff:ffff:ffff:ffff
622e2d:3d00::/242e2d:3dff:ffff:ffff:ffff:ffff:ffff:ffff
632e2d:3e00::/242e2d:3eff:ffff:ffff:ffff:ffff:ffff:ffff
642e2d:3f00::/242e2d:3fff:ffff:ffff:ffff:ffff:ffff:ffff
652e2d:4000::/242e2d:40ff:ffff:ffff:ffff:ffff:ffff:ffff
662e2d:4100::/242e2d:41ff:ffff:ffff:ffff:ffff:ffff:ffff
672e2d:4200::/242e2d:42ff:ffff:ffff:ffff:ffff:ffff:ffff
682e2d:4300::/242e2d:43ff:ffff:ffff:ffff:ffff:ffff:ffff
692e2d:4400::/242e2d:44ff:ffff:ffff:ffff:ffff:ffff:ffff
702e2d:4500::/242e2d:45ff:ffff:ffff:ffff:ffff:ffff:ffff
712e2d:4600::/242e2d:46ff:ffff:ffff:ffff:ffff:ffff:ffff
722e2d:4700::/242e2d:47ff:ffff:ffff:ffff:ffff:ffff:ffff
732e2d:4800::/242e2d:48ff:ffff:ffff:ffff:ffff:ffff:ffff
742e2d:4900::/242e2d:49ff:ffff:ffff:ffff:ffff:ffff:ffff
752e2d:4a00::/242e2d:4aff:ffff:ffff:ffff:ffff:ffff:ffff
762e2d:4b00::/242e2d:4bff:ffff:ffff:ffff:ffff:ffff:ffff
772e2d:4c00::/242e2d:4cff:ffff:ffff:ffff:ffff:ffff:ffff
782e2d:4d00::/242e2d:4dff:ffff:ffff:ffff:ffff:ffff:ffff
792e2d:4e00::/242e2d:4eff:ffff:ffff:ffff:ffff:ffff:ffff
802e2d:4f00::/242e2d:4fff:ffff:ffff:ffff:ffff:ffff:ffff
812e2d:5000::/242e2d:50ff:ffff:ffff:ffff:ffff:ffff:ffff
822e2d:5100::/242e2d:51ff:ffff:ffff:ffff:ffff:ffff:ffff
832e2d:5200::/242e2d:52ff:ffff:ffff:ffff:ffff:ffff:ffff
842e2d:5300::/242e2d:53ff:ffff:ffff:ffff:ffff:ffff:ffff
852e2d:5400::/242e2d:54ff:ffff:ffff:ffff:ffff:ffff:ffff
862e2d:5500::/242e2d:55ff:ffff:ffff:ffff:ffff:ffff:ffff
872e2d:5600::/242e2d:56ff:ffff:ffff:ffff:ffff:ffff:ffff
882e2d:5700::/242e2d:57ff:ffff:ffff:ffff:ffff:ffff:ffff
892e2d:5800::/242e2d:58ff:ffff:ffff:ffff:ffff:ffff:ffff
902e2d:5900::/242e2d:59ff:ffff:ffff:ffff:ffff:ffff:ffff
912e2d:5a00::/242e2d:5aff:ffff:ffff:ffff:ffff:ffff:ffff
922e2d:5b00::/242e2d:5bff:ffff:ffff:ffff:ffff:ffff:ffff
932e2d:5c00::/242e2d:5cff:ffff:ffff:ffff:ffff:ffff:ffff
942e2d:5d00::/242e2d:5dff:ffff:ffff:ffff:ffff:ffff:ffff
952e2d:5e00::/242e2d:5eff:ffff:ffff:ffff:ffff:ffff:ffff
962e2d:5f00::/242e2d:5fff:ffff:ffff:ffff:ffff:ffff:ffff
972e2d:6000::/242e2d:60ff:ffff:ffff:ffff:ffff:ffff:ffff
982e2d:6100::/242e2d:61ff:ffff:ffff:ffff:ffff:ffff:ffff
992e2d:6200::/242e2d:62ff:ffff:ffff:ffff:ffff:ffff:ffff
1002e2d:6300::/242e2d:63ff:ffff:ffff:ffff:ffff:ffff:ffff
1012e2d:6400::/242e2d:64ff:ffff:ffff:ffff:ffff:ffff:ffff
1022e2d:6500::/242e2d:65ff:ffff:ffff:ffff:ffff:ffff:ffff
1032e2d:6600::/242e2d:66ff:ffff:ffff:ffff:ffff:ffff:ffff
1042e2d:6700::/242e2d:67ff:ffff:ffff:ffff:ffff:ffff:ffff
1052e2d:6800::/242e2d:68ff:ffff:ffff:ffff:ffff:ffff:ffff
1062e2d:6900::/242e2d:69ff:ffff:ffff:ffff:ffff:ffff:ffff
1072e2d:6a00::/242e2d:6aff:ffff:ffff:ffff:ffff:ffff:ffff
1082e2d:6b00::/242e2d:6bff:ffff:ffff:ffff:ffff:ffff:ffff
1092e2d:6c00::/242e2d:6cff:ffff:ffff:ffff:ffff:ffff:ffff
1102e2d:6d00::/242e2d:6dff:ffff:ffff:ffff:ffff:ffff:ffff
1112e2d:6e00::/242e2d:6eff:ffff:ffff:ffff:ffff:ffff:ffff
1122e2d:6f00::/242e2d:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1132e2d:7000::/242e2d:70ff:ffff:ffff:ffff:ffff:ffff:ffff
1142e2d:7100::/242e2d:71ff:ffff:ffff:ffff:ffff:ffff:ffff
1152e2d:7200::/242e2d:72ff:ffff:ffff:ffff:ffff:ffff:ffff
1162e2d:7300::/242e2d:73ff:ffff:ffff:ffff:ffff:ffff:ffff
1172e2d:7400::/242e2d:74ff:ffff:ffff:ffff:ffff:ffff:ffff
1182e2d:7500::/242e2d:75ff:ffff:ffff:ffff:ffff:ffff:ffff
1192e2d:7600::/242e2d:76ff:ffff:ffff:ffff:ffff:ffff:ffff
1202e2d:7700::/242e2d:77ff:ffff:ffff:ffff:ffff:ffff:ffff
1212e2d:7800::/242e2d:78ff:ffff:ffff:ffff:ffff:ffff:ffff
1222e2d:7900::/242e2d:79ff:ffff:ffff:ffff:ffff:ffff:ffff
1232e2d:7a00::/242e2d:7aff:ffff:ffff:ffff:ffff:ffff:ffff
1242e2d:7b00::/242e2d:7bff:ffff:ffff:ffff:ffff:ffff:ffff
1252e2d:7c00::/242e2d:7cff:ffff:ffff:ffff:ffff:ffff:ffff
1262e2d:7d00::/242e2d:7dff:ffff:ffff:ffff:ffff:ffff:ffff
1272e2d:7e00::/242e2d:7eff:ffff:ffff:ffff:ffff:ffff:ffff
1282e2d:7f00::/242e2d:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1292e2d:8000::/242e2d:80ff:ffff:ffff:ffff:ffff:ffff:ffff
1302e2d:8100::/242e2d:81ff:ffff:ffff:ffff:ffff:ffff:ffff
1312e2d:8200::/242e2d:82ff:ffff:ffff:ffff:ffff:ffff:ffff
1322e2d:8300::/242e2d:83ff:ffff:ffff:ffff:ffff:ffff:ffff
1332e2d:8400::/242e2d:84ff:ffff:ffff:ffff:ffff:ffff:ffff
1342e2d:8500::/242e2d:85ff:ffff:ffff:ffff:ffff:ffff:ffff
1352e2d:8600::/242e2d:86ff:ffff:ffff:ffff:ffff:ffff:ffff
1362e2d:8700::/242e2d:87ff:ffff:ffff:ffff:ffff:ffff:ffff
1372e2d:8800::/242e2d:88ff:ffff:ffff:ffff:ffff:ffff:ffff
1382e2d:8900::/242e2d:89ff:ffff:ffff:ffff:ffff:ffff:ffff
1392e2d:8a00::/242e2d:8aff:ffff:ffff:ffff:ffff:ffff:ffff
1402e2d:8b00::/242e2d:8bff:ffff:ffff:ffff:ffff:ffff:ffff
1412e2d:8c00::/242e2d:8cff:ffff:ffff:ffff:ffff:ffff:ffff
1422e2d:8d00::/242e2d:8dff:ffff:ffff:ffff:ffff:ffff:ffff
1432e2d:8e00::/242e2d:8eff:ffff:ffff:ffff:ffff:ffff:ffff
1442e2d:8f00::/242e2d:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1452e2d:9000::/242e2d:90ff:ffff:ffff:ffff:ffff:ffff:ffff
1462e2d:9100::/242e2d:91ff:ffff:ffff:ffff:ffff:ffff:ffff
1472e2d:9200::/242e2d:92ff:ffff:ffff:ffff:ffff:ffff:ffff
1482e2d:9300::/242e2d:93ff:ffff:ffff:ffff:ffff:ffff:ffff
1492e2d:9400::/242e2d:94ff:ffff:ffff:ffff:ffff:ffff:ffff
1502e2d:9500::/242e2d:95ff:ffff:ffff:ffff:ffff:ffff:ffff
1512e2d:9600::/242e2d:96ff:ffff:ffff:ffff:ffff:ffff:ffff
1522e2d:9700::/242e2d:97ff:ffff:ffff:ffff:ffff:ffff:ffff
1532e2d:9800::/242e2d:98ff:ffff:ffff:ffff:ffff:ffff:ffff
1542e2d:9900::/242e2d:99ff:ffff:ffff:ffff:ffff:ffff:ffff
1552e2d:9a00::/242e2d:9aff:ffff:ffff:ffff:ffff:ffff:ffff
1562e2d:9b00::/242e2d:9bff:ffff:ffff:ffff:ffff:ffff:ffff
1572e2d:9c00::/242e2d:9cff:ffff:ffff:ffff:ffff:ffff:ffff
1582e2d:9d00::/242e2d:9dff:ffff:ffff:ffff:ffff:ffff:ffff
1592e2d:9e00::/242e2d:9eff:ffff:ffff:ffff:ffff:ffff:ffff
1602e2d:9f00::/242e2d:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1612e2d:a000::/242e2d:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
1622e2d:a100::/242e2d:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
1632e2d:a200::/242e2d:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
1642e2d:a300::/242e2d:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
1652e2d:a400::/242e2d:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
1662e2d:a500::/242e2d:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
1672e2d:a600::/242e2d:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
1682e2d:a700::/242e2d:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
1692e2d:a800::/242e2d:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
1702e2d:a900::/242e2d:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
1712e2d:aa00::/242e2d:aaff:ffff:ffff:ffff:ffff:ffff:ffff
1722e2d:ab00::/242e2d:abff:ffff:ffff:ffff:ffff:ffff:ffff
1732e2d:ac00::/242e2d:acff:ffff:ffff:ffff:ffff:ffff:ffff
1742e2d:ad00::/242e2d:adff:ffff:ffff:ffff:ffff:ffff:ffff
1752e2d:ae00::/242e2d:aeff:ffff:ffff:ffff:ffff:ffff:ffff
1762e2d:af00::/242e2d:afff:ffff:ffff:ffff:ffff:ffff:ffff
1772e2d:b000::/242e2d:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
1782e2d:b100::/242e2d:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
1792e2d:b200::/242e2d:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
1802e2d:b300::/242e2d:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
1812e2d:b400::/242e2d:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
1822e2d:b500::/242e2d:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
1832e2d:b600::/242e2d:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
1842e2d:b700::/242e2d:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
1852e2d:b800::/242e2d:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
1862e2d:b900::/242e2d:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
1872e2d:ba00::/242e2d:baff:ffff:ffff:ffff:ffff:ffff:ffff
1882e2d:bb00::/242e2d:bbff:ffff:ffff:ffff:ffff:ffff:ffff
1892e2d:bc00::/242e2d:bcff:ffff:ffff:ffff:ffff:ffff:ffff
1902e2d:bd00::/242e2d:bdff:ffff:ffff:ffff:ffff:ffff:ffff
1912e2d:be00::/242e2d:beff:ffff:ffff:ffff:ffff:ffff:ffff
1922e2d:bf00::/242e2d:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1932e2d:c000::/242e2d:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
1942e2d:c100::/242e2d:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
1952e2d:c200::/242e2d:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
1962e2d:c300::/242e2d:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
1972e2d:c400::/242e2d:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
1982e2d:c500::/242e2d:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
1992e2d:c600::/242e2d:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
2002e2d:c700::/242e2d:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
2012e2d:c800::/242e2d:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
2022e2d:c900::/242e2d:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
2032e2d:ca00::/242e2d:caff:ffff:ffff:ffff:ffff:ffff:ffff
2042e2d:cb00::/242e2d:cbff:ffff:ffff:ffff:ffff:ffff:ffff
2052e2d:cc00::/242e2d:ccff:ffff:ffff:ffff:ffff:ffff:ffff
2062e2d:cd00::/242e2d:cdff:ffff:ffff:ffff:ffff:ffff:ffff
2072e2d:ce00::/242e2d:ceff:ffff:ffff:ffff:ffff:ffff:ffff
2082e2d:cf00::/242e2d:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2092e2d:d000::/242e2d:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
2102e2d:d100::/242e2d:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
2112e2d:d200::/242e2d:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
2122e2d:d300::/242e2d:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
2132e2d:d400::/242e2d:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
2142e2d:d500::/242e2d:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
2152e2d:d600::/242e2d:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
2162e2d:d700::/242e2d:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
2172e2d:d800::/242e2d:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
2182e2d:d900::/242e2d:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
2192e2d:da00::/242e2d:daff:ffff:ffff:ffff:ffff:ffff:ffff
2202e2d:db00::/242e2d:dbff:ffff:ffff:ffff:ffff:ffff:ffff
2212e2d:dc00::/242e2d:dcff:ffff:ffff:ffff:ffff:ffff:ffff
2222e2d:dd00::/242e2d:ddff:ffff:ffff:ffff:ffff:ffff:ffff
2232e2d:de00::/242e2d:deff:ffff:ffff:ffff:ffff:ffff:ffff
2242e2d:df00::/242e2d:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2252e2d:e000::/242e2d:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
2262e2d:e100::/242e2d:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
2272e2d:e200::/242e2d:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
2282e2d:e300::/242e2d:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
2292e2d:e400::/242e2d:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
2302e2d:e500::/242e2d:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
2312e2d:e600::/242e2d:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
2322e2d:e700::/242e2d:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
2332e2d:e800::/242e2d:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
2342e2d:e900::/242e2d:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
2352e2d:ea00::/242e2d:eaff:ffff:ffff:ffff:ffff:ffff:ffff
2362e2d:eb00::/242e2d:ebff:ffff:ffff:ffff:ffff:ffff:ffff
2372e2d:ec00::/242e2d:ecff:ffff:ffff:ffff:ffff:ffff:ffff
2382e2d:ed00::/242e2d:edff:ffff:ffff:ffff:ffff:ffff:ffff
2392e2d:ee00::/242e2d:eeff:ffff:ffff:ffff:ffff:ffff:ffff
2402e2d:ef00::/242e2d:efff:ffff:ffff:ffff:ffff:ffff:ffff
2412e2d:f000::/242e2d:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
2422e2d:f100::/242e2d:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
2432e2d:f200::/242e2d:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
2442e2d:f300::/242e2d:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
2452e2d:f400::/242e2d:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
2462e2d:f500::/242e2d:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
2472e2d:f600::/242e2d:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
2482e2d:f700::/242e2d:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
2492e2d:f800::/242e2d:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
2502e2d:f900::/242e2d:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
2512e2d:fa00::/242e2d:faff:ffff:ffff:ffff:ffff:ffff:ffff
2522e2d:fb00::/242e2d:fbff:ffff:ffff:ffff:ffff:ffff:ffff
2532e2d:fc00::/242e2d:fcff:ffff:ffff:ffff:ffff:ffff:ffff
2542e2d:fd00::/242e2d:fdff:ffff:ffff:ffff:ffff:ffff:ffff
2552e2d:fe00::/242e2d:feff:ffff:ffff:ffff:ffff:ffff:ffff
2562e2d:ff00::/242e2d: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.