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

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

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