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

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

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