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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
3a4e::/16
First address
3a4e::
Last address
3a4e: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
3a4e:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
e.4.a.3.ip6.arpa
Split into smaller subnets/24
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

3a4e::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
13a4e::/243a4e:ff:ffff:ffff:ffff:ffff:ffff:ffff
23a4e:100::/243a4e:1ff:ffff:ffff:ffff:ffff:ffff:ffff
33a4e:200::/243a4e:2ff:ffff:ffff:ffff:ffff:ffff:ffff
43a4e:300::/243a4e:3ff:ffff:ffff:ffff:ffff:ffff:ffff
53a4e:400::/243a4e:4ff:ffff:ffff:ffff:ffff:ffff:ffff
63a4e:500::/243a4e:5ff:ffff:ffff:ffff:ffff:ffff:ffff
73a4e:600::/243a4e:6ff:ffff:ffff:ffff:ffff:ffff:ffff
83a4e:700::/243a4e:7ff:ffff:ffff:ffff:ffff:ffff:ffff
93a4e:800::/243a4e:8ff:ffff:ffff:ffff:ffff:ffff:ffff
103a4e:900::/243a4e:9ff:ffff:ffff:ffff:ffff:ffff:ffff
113a4e:a00::/243a4e:aff:ffff:ffff:ffff:ffff:ffff:ffff
123a4e:b00::/243a4e:bff:ffff:ffff:ffff:ffff:ffff:ffff
133a4e:c00::/243a4e:cff:ffff:ffff:ffff:ffff:ffff:ffff
143a4e:d00::/243a4e:dff:ffff:ffff:ffff:ffff:ffff:ffff
153a4e:e00::/243a4e:eff:ffff:ffff:ffff:ffff:ffff:ffff
163a4e:f00::/243a4e:fff:ffff:ffff:ffff:ffff:ffff:ffff
173a4e:1000::/243a4e:10ff:ffff:ffff:ffff:ffff:ffff:ffff
183a4e:1100::/243a4e:11ff:ffff:ffff:ffff:ffff:ffff:ffff
193a4e:1200::/243a4e:12ff:ffff:ffff:ffff:ffff:ffff:ffff
203a4e:1300::/243a4e:13ff:ffff:ffff:ffff:ffff:ffff:ffff
213a4e:1400::/243a4e:14ff:ffff:ffff:ffff:ffff:ffff:ffff
223a4e:1500::/243a4e:15ff:ffff:ffff:ffff:ffff:ffff:ffff
233a4e:1600::/243a4e:16ff:ffff:ffff:ffff:ffff:ffff:ffff
243a4e:1700::/243a4e:17ff:ffff:ffff:ffff:ffff:ffff:ffff
253a4e:1800::/243a4e:18ff:ffff:ffff:ffff:ffff:ffff:ffff
263a4e:1900::/243a4e:19ff:ffff:ffff:ffff:ffff:ffff:ffff
273a4e:1a00::/243a4e:1aff:ffff:ffff:ffff:ffff:ffff:ffff
283a4e:1b00::/243a4e:1bff:ffff:ffff:ffff:ffff:ffff:ffff
293a4e:1c00::/243a4e:1cff:ffff:ffff:ffff:ffff:ffff:ffff
303a4e:1d00::/243a4e:1dff:ffff:ffff:ffff:ffff:ffff:ffff
313a4e:1e00::/243a4e:1eff:ffff:ffff:ffff:ffff:ffff:ffff
323a4e:1f00::/243a4e:1fff:ffff:ffff:ffff:ffff:ffff:ffff
333a4e:2000::/243a4e:20ff:ffff:ffff:ffff:ffff:ffff:ffff
343a4e:2100::/243a4e:21ff:ffff:ffff:ffff:ffff:ffff:ffff
353a4e:2200::/243a4e:22ff:ffff:ffff:ffff:ffff:ffff:ffff
363a4e:2300::/243a4e:23ff:ffff:ffff:ffff:ffff:ffff:ffff
373a4e:2400::/243a4e:24ff:ffff:ffff:ffff:ffff:ffff:ffff
383a4e:2500::/243a4e:25ff:ffff:ffff:ffff:ffff:ffff:ffff
393a4e:2600::/243a4e:26ff:ffff:ffff:ffff:ffff:ffff:ffff
403a4e:2700::/243a4e:27ff:ffff:ffff:ffff:ffff:ffff:ffff
413a4e:2800::/243a4e:28ff:ffff:ffff:ffff:ffff:ffff:ffff
423a4e:2900::/243a4e:29ff:ffff:ffff:ffff:ffff:ffff:ffff
433a4e:2a00::/243a4e:2aff:ffff:ffff:ffff:ffff:ffff:ffff
443a4e:2b00::/243a4e:2bff:ffff:ffff:ffff:ffff:ffff:ffff
453a4e:2c00::/243a4e:2cff:ffff:ffff:ffff:ffff:ffff:ffff
463a4e:2d00::/243a4e:2dff:ffff:ffff:ffff:ffff:ffff:ffff
473a4e:2e00::/243a4e:2eff:ffff:ffff:ffff:ffff:ffff:ffff
483a4e:2f00::/243a4e:2fff:ffff:ffff:ffff:ffff:ffff:ffff
493a4e:3000::/243a4e:30ff:ffff:ffff:ffff:ffff:ffff:ffff
503a4e:3100::/243a4e:31ff:ffff:ffff:ffff:ffff:ffff:ffff
513a4e:3200::/243a4e:32ff:ffff:ffff:ffff:ffff:ffff:ffff
523a4e:3300::/243a4e:33ff:ffff:ffff:ffff:ffff:ffff:ffff
533a4e:3400::/243a4e:34ff:ffff:ffff:ffff:ffff:ffff:ffff
543a4e:3500::/243a4e:35ff:ffff:ffff:ffff:ffff:ffff:ffff
553a4e:3600::/243a4e:36ff:ffff:ffff:ffff:ffff:ffff:ffff
563a4e:3700::/243a4e:37ff:ffff:ffff:ffff:ffff:ffff:ffff
573a4e:3800::/243a4e:38ff:ffff:ffff:ffff:ffff:ffff:ffff
583a4e:3900::/243a4e:39ff:ffff:ffff:ffff:ffff:ffff:ffff
593a4e:3a00::/243a4e:3aff:ffff:ffff:ffff:ffff:ffff:ffff
603a4e:3b00::/243a4e:3bff:ffff:ffff:ffff:ffff:ffff:ffff
613a4e:3c00::/243a4e:3cff:ffff:ffff:ffff:ffff:ffff:ffff
623a4e:3d00::/243a4e:3dff:ffff:ffff:ffff:ffff:ffff:ffff
633a4e:3e00::/243a4e:3eff:ffff:ffff:ffff:ffff:ffff:ffff
643a4e:3f00::/243a4e:3fff:ffff:ffff:ffff:ffff:ffff:ffff
653a4e:4000::/243a4e:40ff:ffff:ffff:ffff:ffff:ffff:ffff
663a4e:4100::/243a4e:41ff:ffff:ffff:ffff:ffff:ffff:ffff
673a4e:4200::/243a4e:42ff:ffff:ffff:ffff:ffff:ffff:ffff
683a4e:4300::/243a4e:43ff:ffff:ffff:ffff:ffff:ffff:ffff
693a4e:4400::/243a4e:44ff:ffff:ffff:ffff:ffff:ffff:ffff
703a4e:4500::/243a4e:45ff:ffff:ffff:ffff:ffff:ffff:ffff
713a4e:4600::/243a4e:46ff:ffff:ffff:ffff:ffff:ffff:ffff
723a4e:4700::/243a4e:47ff:ffff:ffff:ffff:ffff:ffff:ffff
733a4e:4800::/243a4e:48ff:ffff:ffff:ffff:ffff:ffff:ffff
743a4e:4900::/243a4e:49ff:ffff:ffff:ffff:ffff:ffff:ffff
753a4e:4a00::/243a4e:4aff:ffff:ffff:ffff:ffff:ffff:ffff
763a4e:4b00::/243a4e:4bff:ffff:ffff:ffff:ffff:ffff:ffff
773a4e:4c00::/243a4e:4cff:ffff:ffff:ffff:ffff:ffff:ffff
783a4e:4d00::/243a4e:4dff:ffff:ffff:ffff:ffff:ffff:ffff
793a4e:4e00::/243a4e:4eff:ffff:ffff:ffff:ffff:ffff:ffff
803a4e:4f00::/243a4e:4fff:ffff:ffff:ffff:ffff:ffff:ffff
813a4e:5000::/243a4e:50ff:ffff:ffff:ffff:ffff:ffff:ffff
823a4e:5100::/243a4e:51ff:ffff:ffff:ffff:ffff:ffff:ffff
833a4e:5200::/243a4e:52ff:ffff:ffff:ffff:ffff:ffff:ffff
843a4e:5300::/243a4e:53ff:ffff:ffff:ffff:ffff:ffff:ffff
853a4e:5400::/243a4e:54ff:ffff:ffff:ffff:ffff:ffff:ffff
863a4e:5500::/243a4e:55ff:ffff:ffff:ffff:ffff:ffff:ffff
873a4e:5600::/243a4e:56ff:ffff:ffff:ffff:ffff:ffff:ffff
883a4e:5700::/243a4e:57ff:ffff:ffff:ffff:ffff:ffff:ffff
893a4e:5800::/243a4e:58ff:ffff:ffff:ffff:ffff:ffff:ffff
903a4e:5900::/243a4e:59ff:ffff:ffff:ffff:ffff:ffff:ffff
913a4e:5a00::/243a4e:5aff:ffff:ffff:ffff:ffff:ffff:ffff
923a4e:5b00::/243a4e:5bff:ffff:ffff:ffff:ffff:ffff:ffff
933a4e:5c00::/243a4e:5cff:ffff:ffff:ffff:ffff:ffff:ffff
943a4e:5d00::/243a4e:5dff:ffff:ffff:ffff:ffff:ffff:ffff
953a4e:5e00::/243a4e:5eff:ffff:ffff:ffff:ffff:ffff:ffff
963a4e:5f00::/243a4e:5fff:ffff:ffff:ffff:ffff:ffff:ffff
973a4e:6000::/243a4e:60ff:ffff:ffff:ffff:ffff:ffff:ffff
983a4e:6100::/243a4e:61ff:ffff:ffff:ffff:ffff:ffff:ffff
993a4e:6200::/243a4e:62ff:ffff:ffff:ffff:ffff:ffff:ffff
1003a4e:6300::/243a4e:63ff:ffff:ffff:ffff:ffff:ffff:ffff
1013a4e:6400::/243a4e:64ff:ffff:ffff:ffff:ffff:ffff:ffff
1023a4e:6500::/243a4e:65ff:ffff:ffff:ffff:ffff:ffff:ffff
1033a4e:6600::/243a4e:66ff:ffff:ffff:ffff:ffff:ffff:ffff
1043a4e:6700::/243a4e:67ff:ffff:ffff:ffff:ffff:ffff:ffff
1053a4e:6800::/243a4e:68ff:ffff:ffff:ffff:ffff:ffff:ffff
1063a4e:6900::/243a4e:69ff:ffff:ffff:ffff:ffff:ffff:ffff
1073a4e:6a00::/243a4e:6aff:ffff:ffff:ffff:ffff:ffff:ffff
1083a4e:6b00::/243a4e:6bff:ffff:ffff:ffff:ffff:ffff:ffff
1093a4e:6c00::/243a4e:6cff:ffff:ffff:ffff:ffff:ffff:ffff
1103a4e:6d00::/243a4e:6dff:ffff:ffff:ffff:ffff:ffff:ffff
1113a4e:6e00::/243a4e:6eff:ffff:ffff:ffff:ffff:ffff:ffff
1123a4e:6f00::/243a4e:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1133a4e:7000::/243a4e:70ff:ffff:ffff:ffff:ffff:ffff:ffff
1143a4e:7100::/243a4e:71ff:ffff:ffff:ffff:ffff:ffff:ffff
1153a4e:7200::/243a4e:72ff:ffff:ffff:ffff:ffff:ffff:ffff
1163a4e:7300::/243a4e:73ff:ffff:ffff:ffff:ffff:ffff:ffff
1173a4e:7400::/243a4e:74ff:ffff:ffff:ffff:ffff:ffff:ffff
1183a4e:7500::/243a4e:75ff:ffff:ffff:ffff:ffff:ffff:ffff
1193a4e:7600::/243a4e:76ff:ffff:ffff:ffff:ffff:ffff:ffff
1203a4e:7700::/243a4e:77ff:ffff:ffff:ffff:ffff:ffff:ffff
1213a4e:7800::/243a4e:78ff:ffff:ffff:ffff:ffff:ffff:ffff
1223a4e:7900::/243a4e:79ff:ffff:ffff:ffff:ffff:ffff:ffff
1233a4e:7a00::/243a4e:7aff:ffff:ffff:ffff:ffff:ffff:ffff
1243a4e:7b00::/243a4e:7bff:ffff:ffff:ffff:ffff:ffff:ffff
1253a4e:7c00::/243a4e:7cff:ffff:ffff:ffff:ffff:ffff:ffff
1263a4e:7d00::/243a4e:7dff:ffff:ffff:ffff:ffff:ffff:ffff
1273a4e:7e00::/243a4e:7eff:ffff:ffff:ffff:ffff:ffff:ffff
1283a4e:7f00::/243a4e:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1293a4e:8000::/243a4e:80ff:ffff:ffff:ffff:ffff:ffff:ffff
1303a4e:8100::/243a4e:81ff:ffff:ffff:ffff:ffff:ffff:ffff
1313a4e:8200::/243a4e:82ff:ffff:ffff:ffff:ffff:ffff:ffff
1323a4e:8300::/243a4e:83ff:ffff:ffff:ffff:ffff:ffff:ffff
1333a4e:8400::/243a4e:84ff:ffff:ffff:ffff:ffff:ffff:ffff
1343a4e:8500::/243a4e:85ff:ffff:ffff:ffff:ffff:ffff:ffff
1353a4e:8600::/243a4e:86ff:ffff:ffff:ffff:ffff:ffff:ffff
1363a4e:8700::/243a4e:87ff:ffff:ffff:ffff:ffff:ffff:ffff
1373a4e:8800::/243a4e:88ff:ffff:ffff:ffff:ffff:ffff:ffff
1383a4e:8900::/243a4e:89ff:ffff:ffff:ffff:ffff:ffff:ffff
1393a4e:8a00::/243a4e:8aff:ffff:ffff:ffff:ffff:ffff:ffff
1403a4e:8b00::/243a4e:8bff:ffff:ffff:ffff:ffff:ffff:ffff
1413a4e:8c00::/243a4e:8cff:ffff:ffff:ffff:ffff:ffff:ffff
1423a4e:8d00::/243a4e:8dff:ffff:ffff:ffff:ffff:ffff:ffff
1433a4e:8e00::/243a4e:8eff:ffff:ffff:ffff:ffff:ffff:ffff
1443a4e:8f00::/243a4e:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1453a4e:9000::/243a4e:90ff:ffff:ffff:ffff:ffff:ffff:ffff
1463a4e:9100::/243a4e:91ff:ffff:ffff:ffff:ffff:ffff:ffff
1473a4e:9200::/243a4e:92ff:ffff:ffff:ffff:ffff:ffff:ffff
1483a4e:9300::/243a4e:93ff:ffff:ffff:ffff:ffff:ffff:ffff
1493a4e:9400::/243a4e:94ff:ffff:ffff:ffff:ffff:ffff:ffff
1503a4e:9500::/243a4e:95ff:ffff:ffff:ffff:ffff:ffff:ffff
1513a4e:9600::/243a4e:96ff:ffff:ffff:ffff:ffff:ffff:ffff
1523a4e:9700::/243a4e:97ff:ffff:ffff:ffff:ffff:ffff:ffff
1533a4e:9800::/243a4e:98ff:ffff:ffff:ffff:ffff:ffff:ffff
1543a4e:9900::/243a4e:99ff:ffff:ffff:ffff:ffff:ffff:ffff
1553a4e:9a00::/243a4e:9aff:ffff:ffff:ffff:ffff:ffff:ffff
1563a4e:9b00::/243a4e:9bff:ffff:ffff:ffff:ffff:ffff:ffff
1573a4e:9c00::/243a4e:9cff:ffff:ffff:ffff:ffff:ffff:ffff
1583a4e:9d00::/243a4e:9dff:ffff:ffff:ffff:ffff:ffff:ffff
1593a4e:9e00::/243a4e:9eff:ffff:ffff:ffff:ffff:ffff:ffff
1603a4e:9f00::/243a4e:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1613a4e:a000::/243a4e:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
1623a4e:a100::/243a4e:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
1633a4e:a200::/243a4e:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
1643a4e:a300::/243a4e:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
1653a4e:a400::/243a4e:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
1663a4e:a500::/243a4e:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
1673a4e:a600::/243a4e:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
1683a4e:a700::/243a4e:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
1693a4e:a800::/243a4e:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
1703a4e:a900::/243a4e:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
1713a4e:aa00::/243a4e:aaff:ffff:ffff:ffff:ffff:ffff:ffff
1723a4e:ab00::/243a4e:abff:ffff:ffff:ffff:ffff:ffff:ffff
1733a4e:ac00::/243a4e:acff:ffff:ffff:ffff:ffff:ffff:ffff
1743a4e:ad00::/243a4e:adff:ffff:ffff:ffff:ffff:ffff:ffff
1753a4e:ae00::/243a4e:aeff:ffff:ffff:ffff:ffff:ffff:ffff
1763a4e:af00::/243a4e:afff:ffff:ffff:ffff:ffff:ffff:ffff
1773a4e:b000::/243a4e:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
1783a4e:b100::/243a4e:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
1793a4e:b200::/243a4e:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
1803a4e:b300::/243a4e:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
1813a4e:b400::/243a4e:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
1823a4e:b500::/243a4e:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
1833a4e:b600::/243a4e:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
1843a4e:b700::/243a4e:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
1853a4e:b800::/243a4e:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
1863a4e:b900::/243a4e:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
1873a4e:ba00::/243a4e:baff:ffff:ffff:ffff:ffff:ffff:ffff
1883a4e:bb00::/243a4e:bbff:ffff:ffff:ffff:ffff:ffff:ffff
1893a4e:bc00::/243a4e:bcff:ffff:ffff:ffff:ffff:ffff:ffff
1903a4e:bd00::/243a4e:bdff:ffff:ffff:ffff:ffff:ffff:ffff
1913a4e:be00::/243a4e:beff:ffff:ffff:ffff:ffff:ffff:ffff
1923a4e:bf00::/243a4e:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1933a4e:c000::/243a4e:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
1943a4e:c100::/243a4e:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
1953a4e:c200::/243a4e:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
1963a4e:c300::/243a4e:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
1973a4e:c400::/243a4e:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
1983a4e:c500::/243a4e:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
1993a4e:c600::/243a4e:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
2003a4e:c700::/243a4e:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
2013a4e:c800::/243a4e:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
2023a4e:c900::/243a4e:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
2033a4e:ca00::/243a4e:caff:ffff:ffff:ffff:ffff:ffff:ffff
2043a4e:cb00::/243a4e:cbff:ffff:ffff:ffff:ffff:ffff:ffff
2053a4e:cc00::/243a4e:ccff:ffff:ffff:ffff:ffff:ffff:ffff
2063a4e:cd00::/243a4e:cdff:ffff:ffff:ffff:ffff:ffff:ffff
2073a4e:ce00::/243a4e:ceff:ffff:ffff:ffff:ffff:ffff:ffff
2083a4e:cf00::/243a4e:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2093a4e:d000::/243a4e:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
2103a4e:d100::/243a4e:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
2113a4e:d200::/243a4e:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
2123a4e:d300::/243a4e:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
2133a4e:d400::/243a4e:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
2143a4e:d500::/243a4e:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
2153a4e:d600::/243a4e:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
2163a4e:d700::/243a4e:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
2173a4e:d800::/243a4e:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
2183a4e:d900::/243a4e:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
2193a4e:da00::/243a4e:daff:ffff:ffff:ffff:ffff:ffff:ffff
2203a4e:db00::/243a4e:dbff:ffff:ffff:ffff:ffff:ffff:ffff
2213a4e:dc00::/243a4e:dcff:ffff:ffff:ffff:ffff:ffff:ffff
2223a4e:dd00::/243a4e:ddff:ffff:ffff:ffff:ffff:ffff:ffff
2233a4e:de00::/243a4e:deff:ffff:ffff:ffff:ffff:ffff:ffff
2243a4e:df00::/243a4e:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2253a4e:e000::/243a4e:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
2263a4e:e100::/243a4e:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
2273a4e:e200::/243a4e:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
2283a4e:e300::/243a4e:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
2293a4e:e400::/243a4e:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
2303a4e:e500::/243a4e:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
2313a4e:e600::/243a4e:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
2323a4e:e700::/243a4e:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
2333a4e:e800::/243a4e:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
2343a4e:e900::/243a4e:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
2353a4e:ea00::/243a4e:eaff:ffff:ffff:ffff:ffff:ffff:ffff
2363a4e:eb00::/243a4e:ebff:ffff:ffff:ffff:ffff:ffff:ffff
2373a4e:ec00::/243a4e:ecff:ffff:ffff:ffff:ffff:ffff:ffff
2383a4e:ed00::/243a4e:edff:ffff:ffff:ffff:ffff:ffff:ffff
2393a4e:ee00::/243a4e:eeff:ffff:ffff:ffff:ffff:ffff:ffff
2403a4e:ef00::/243a4e:efff:ffff:ffff:ffff:ffff:ffff:ffff
2413a4e:f000::/243a4e:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
2423a4e:f100::/243a4e:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
2433a4e:f200::/243a4e:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
2443a4e:f300::/243a4e:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
2453a4e:f400::/243a4e:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
2463a4e:f500::/243a4e:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
2473a4e:f600::/243a4e:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
2483a4e:f700::/243a4e:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
2493a4e:f800::/243a4e:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
2503a4e:f900::/243a4e:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
2513a4e:fa00::/243a4e:faff:ffff:ffff:ffff:ffff:ffff:ffff
2523a4e:fb00::/243a4e:fbff:ffff:ffff:ffff:ffff:ffff:ffff
2533a4e:fc00::/243a4e:fcff:ffff:ffff:ffff:ffff:ffff:ffff
2543a4e:fd00::/243a4e:fdff:ffff:ffff:ffff:ffff:ffff:ffff
2553a4e:fe00::/243a4e:feff:ffff:ffff:ffff:ffff:ffff:ffff
2563a4e:ff00::/243a4e: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.