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

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

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