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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
2078::/16
First address
2078::
Last address
2078: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
2078:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
8.7.0.2.ip6.arpa
Split into smaller subnets/24
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

2078::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
12078::/242078:ff:ffff:ffff:ffff:ffff:ffff:ffff
22078:100::/242078:1ff:ffff:ffff:ffff:ffff:ffff:ffff
32078:200::/242078:2ff:ffff:ffff:ffff:ffff:ffff:ffff
42078:300::/242078:3ff:ffff:ffff:ffff:ffff:ffff:ffff
52078:400::/242078:4ff:ffff:ffff:ffff:ffff:ffff:ffff
62078:500::/242078:5ff:ffff:ffff:ffff:ffff:ffff:ffff
72078:600::/242078:6ff:ffff:ffff:ffff:ffff:ffff:ffff
82078:700::/242078:7ff:ffff:ffff:ffff:ffff:ffff:ffff
92078:800::/242078:8ff:ffff:ffff:ffff:ffff:ffff:ffff
102078:900::/242078:9ff:ffff:ffff:ffff:ffff:ffff:ffff
112078:a00::/242078:aff:ffff:ffff:ffff:ffff:ffff:ffff
122078:b00::/242078:bff:ffff:ffff:ffff:ffff:ffff:ffff
132078:c00::/242078:cff:ffff:ffff:ffff:ffff:ffff:ffff
142078:d00::/242078:dff:ffff:ffff:ffff:ffff:ffff:ffff
152078:e00::/242078:eff:ffff:ffff:ffff:ffff:ffff:ffff
162078:f00::/242078:fff:ffff:ffff:ffff:ffff:ffff:ffff
172078:1000::/242078:10ff:ffff:ffff:ffff:ffff:ffff:ffff
182078:1100::/242078:11ff:ffff:ffff:ffff:ffff:ffff:ffff
192078:1200::/242078:12ff:ffff:ffff:ffff:ffff:ffff:ffff
202078:1300::/242078:13ff:ffff:ffff:ffff:ffff:ffff:ffff
212078:1400::/242078:14ff:ffff:ffff:ffff:ffff:ffff:ffff
222078:1500::/242078:15ff:ffff:ffff:ffff:ffff:ffff:ffff
232078:1600::/242078:16ff:ffff:ffff:ffff:ffff:ffff:ffff
242078:1700::/242078:17ff:ffff:ffff:ffff:ffff:ffff:ffff
252078:1800::/242078:18ff:ffff:ffff:ffff:ffff:ffff:ffff
262078:1900::/242078:19ff:ffff:ffff:ffff:ffff:ffff:ffff
272078:1a00::/242078:1aff:ffff:ffff:ffff:ffff:ffff:ffff
282078:1b00::/242078:1bff:ffff:ffff:ffff:ffff:ffff:ffff
292078:1c00::/242078:1cff:ffff:ffff:ffff:ffff:ffff:ffff
302078:1d00::/242078:1dff:ffff:ffff:ffff:ffff:ffff:ffff
312078:1e00::/242078:1eff:ffff:ffff:ffff:ffff:ffff:ffff
322078:1f00::/242078:1fff:ffff:ffff:ffff:ffff:ffff:ffff
332078:2000::/242078:20ff:ffff:ffff:ffff:ffff:ffff:ffff
342078:2100::/242078:21ff:ffff:ffff:ffff:ffff:ffff:ffff
352078:2200::/242078:22ff:ffff:ffff:ffff:ffff:ffff:ffff
362078:2300::/242078:23ff:ffff:ffff:ffff:ffff:ffff:ffff
372078:2400::/242078:24ff:ffff:ffff:ffff:ffff:ffff:ffff
382078:2500::/242078:25ff:ffff:ffff:ffff:ffff:ffff:ffff
392078:2600::/242078:26ff:ffff:ffff:ffff:ffff:ffff:ffff
402078:2700::/242078:27ff:ffff:ffff:ffff:ffff:ffff:ffff
412078:2800::/242078:28ff:ffff:ffff:ffff:ffff:ffff:ffff
422078:2900::/242078:29ff:ffff:ffff:ffff:ffff:ffff:ffff
432078:2a00::/242078:2aff:ffff:ffff:ffff:ffff:ffff:ffff
442078:2b00::/242078:2bff:ffff:ffff:ffff:ffff:ffff:ffff
452078:2c00::/242078:2cff:ffff:ffff:ffff:ffff:ffff:ffff
462078:2d00::/242078:2dff:ffff:ffff:ffff:ffff:ffff:ffff
472078:2e00::/242078:2eff:ffff:ffff:ffff:ffff:ffff:ffff
482078:2f00::/242078:2fff:ffff:ffff:ffff:ffff:ffff:ffff
492078:3000::/242078:30ff:ffff:ffff:ffff:ffff:ffff:ffff
502078:3100::/242078:31ff:ffff:ffff:ffff:ffff:ffff:ffff
512078:3200::/242078:32ff:ffff:ffff:ffff:ffff:ffff:ffff
522078:3300::/242078:33ff:ffff:ffff:ffff:ffff:ffff:ffff
532078:3400::/242078:34ff:ffff:ffff:ffff:ffff:ffff:ffff
542078:3500::/242078:35ff:ffff:ffff:ffff:ffff:ffff:ffff
552078:3600::/242078:36ff:ffff:ffff:ffff:ffff:ffff:ffff
562078:3700::/242078:37ff:ffff:ffff:ffff:ffff:ffff:ffff
572078:3800::/242078:38ff:ffff:ffff:ffff:ffff:ffff:ffff
582078:3900::/242078:39ff:ffff:ffff:ffff:ffff:ffff:ffff
592078:3a00::/242078:3aff:ffff:ffff:ffff:ffff:ffff:ffff
602078:3b00::/242078:3bff:ffff:ffff:ffff:ffff:ffff:ffff
612078:3c00::/242078:3cff:ffff:ffff:ffff:ffff:ffff:ffff
622078:3d00::/242078:3dff:ffff:ffff:ffff:ffff:ffff:ffff
632078:3e00::/242078:3eff:ffff:ffff:ffff:ffff:ffff:ffff
642078:3f00::/242078:3fff:ffff:ffff:ffff:ffff:ffff:ffff
652078:4000::/242078:40ff:ffff:ffff:ffff:ffff:ffff:ffff
662078:4100::/242078:41ff:ffff:ffff:ffff:ffff:ffff:ffff
672078:4200::/242078:42ff:ffff:ffff:ffff:ffff:ffff:ffff
682078:4300::/242078:43ff:ffff:ffff:ffff:ffff:ffff:ffff
692078:4400::/242078:44ff:ffff:ffff:ffff:ffff:ffff:ffff
702078:4500::/242078:45ff:ffff:ffff:ffff:ffff:ffff:ffff
712078:4600::/242078:46ff:ffff:ffff:ffff:ffff:ffff:ffff
722078:4700::/242078:47ff:ffff:ffff:ffff:ffff:ffff:ffff
732078:4800::/242078:48ff:ffff:ffff:ffff:ffff:ffff:ffff
742078:4900::/242078:49ff:ffff:ffff:ffff:ffff:ffff:ffff
752078:4a00::/242078:4aff:ffff:ffff:ffff:ffff:ffff:ffff
762078:4b00::/242078:4bff:ffff:ffff:ffff:ffff:ffff:ffff
772078:4c00::/242078:4cff:ffff:ffff:ffff:ffff:ffff:ffff
782078:4d00::/242078:4dff:ffff:ffff:ffff:ffff:ffff:ffff
792078:4e00::/242078:4eff:ffff:ffff:ffff:ffff:ffff:ffff
802078:4f00::/242078:4fff:ffff:ffff:ffff:ffff:ffff:ffff
812078:5000::/242078:50ff:ffff:ffff:ffff:ffff:ffff:ffff
822078:5100::/242078:51ff:ffff:ffff:ffff:ffff:ffff:ffff
832078:5200::/242078:52ff:ffff:ffff:ffff:ffff:ffff:ffff
842078:5300::/242078:53ff:ffff:ffff:ffff:ffff:ffff:ffff
852078:5400::/242078:54ff:ffff:ffff:ffff:ffff:ffff:ffff
862078:5500::/242078:55ff:ffff:ffff:ffff:ffff:ffff:ffff
872078:5600::/242078:56ff:ffff:ffff:ffff:ffff:ffff:ffff
882078:5700::/242078:57ff:ffff:ffff:ffff:ffff:ffff:ffff
892078:5800::/242078:58ff:ffff:ffff:ffff:ffff:ffff:ffff
902078:5900::/242078:59ff:ffff:ffff:ffff:ffff:ffff:ffff
912078:5a00::/242078:5aff:ffff:ffff:ffff:ffff:ffff:ffff
922078:5b00::/242078:5bff:ffff:ffff:ffff:ffff:ffff:ffff
932078:5c00::/242078:5cff:ffff:ffff:ffff:ffff:ffff:ffff
942078:5d00::/242078:5dff:ffff:ffff:ffff:ffff:ffff:ffff
952078:5e00::/242078:5eff:ffff:ffff:ffff:ffff:ffff:ffff
962078:5f00::/242078:5fff:ffff:ffff:ffff:ffff:ffff:ffff
972078:6000::/242078:60ff:ffff:ffff:ffff:ffff:ffff:ffff
982078:6100::/242078:61ff:ffff:ffff:ffff:ffff:ffff:ffff
992078:6200::/242078:62ff:ffff:ffff:ffff:ffff:ffff:ffff
1002078:6300::/242078:63ff:ffff:ffff:ffff:ffff:ffff:ffff
1012078:6400::/242078:64ff:ffff:ffff:ffff:ffff:ffff:ffff
1022078:6500::/242078:65ff:ffff:ffff:ffff:ffff:ffff:ffff
1032078:6600::/242078:66ff:ffff:ffff:ffff:ffff:ffff:ffff
1042078:6700::/242078:67ff:ffff:ffff:ffff:ffff:ffff:ffff
1052078:6800::/242078:68ff:ffff:ffff:ffff:ffff:ffff:ffff
1062078:6900::/242078:69ff:ffff:ffff:ffff:ffff:ffff:ffff
1072078:6a00::/242078:6aff:ffff:ffff:ffff:ffff:ffff:ffff
1082078:6b00::/242078:6bff:ffff:ffff:ffff:ffff:ffff:ffff
1092078:6c00::/242078:6cff:ffff:ffff:ffff:ffff:ffff:ffff
1102078:6d00::/242078:6dff:ffff:ffff:ffff:ffff:ffff:ffff
1112078:6e00::/242078:6eff:ffff:ffff:ffff:ffff:ffff:ffff
1122078:6f00::/242078:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1132078:7000::/242078:70ff:ffff:ffff:ffff:ffff:ffff:ffff
1142078:7100::/242078:71ff:ffff:ffff:ffff:ffff:ffff:ffff
1152078:7200::/242078:72ff:ffff:ffff:ffff:ffff:ffff:ffff
1162078:7300::/242078:73ff:ffff:ffff:ffff:ffff:ffff:ffff
1172078:7400::/242078:74ff:ffff:ffff:ffff:ffff:ffff:ffff
1182078:7500::/242078:75ff:ffff:ffff:ffff:ffff:ffff:ffff
1192078:7600::/242078:76ff:ffff:ffff:ffff:ffff:ffff:ffff
1202078:7700::/242078:77ff:ffff:ffff:ffff:ffff:ffff:ffff
1212078:7800::/242078:78ff:ffff:ffff:ffff:ffff:ffff:ffff
1222078:7900::/242078:79ff:ffff:ffff:ffff:ffff:ffff:ffff
1232078:7a00::/242078:7aff:ffff:ffff:ffff:ffff:ffff:ffff
1242078:7b00::/242078:7bff:ffff:ffff:ffff:ffff:ffff:ffff
1252078:7c00::/242078:7cff:ffff:ffff:ffff:ffff:ffff:ffff
1262078:7d00::/242078:7dff:ffff:ffff:ffff:ffff:ffff:ffff
1272078:7e00::/242078:7eff:ffff:ffff:ffff:ffff:ffff:ffff
1282078:7f00::/242078:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1292078:8000::/242078:80ff:ffff:ffff:ffff:ffff:ffff:ffff
1302078:8100::/242078:81ff:ffff:ffff:ffff:ffff:ffff:ffff
1312078:8200::/242078:82ff:ffff:ffff:ffff:ffff:ffff:ffff
1322078:8300::/242078:83ff:ffff:ffff:ffff:ffff:ffff:ffff
1332078:8400::/242078:84ff:ffff:ffff:ffff:ffff:ffff:ffff
1342078:8500::/242078:85ff:ffff:ffff:ffff:ffff:ffff:ffff
1352078:8600::/242078:86ff:ffff:ffff:ffff:ffff:ffff:ffff
1362078:8700::/242078:87ff:ffff:ffff:ffff:ffff:ffff:ffff
1372078:8800::/242078:88ff:ffff:ffff:ffff:ffff:ffff:ffff
1382078:8900::/242078:89ff:ffff:ffff:ffff:ffff:ffff:ffff
1392078:8a00::/242078:8aff:ffff:ffff:ffff:ffff:ffff:ffff
1402078:8b00::/242078:8bff:ffff:ffff:ffff:ffff:ffff:ffff
1412078:8c00::/242078:8cff:ffff:ffff:ffff:ffff:ffff:ffff
1422078:8d00::/242078:8dff:ffff:ffff:ffff:ffff:ffff:ffff
1432078:8e00::/242078:8eff:ffff:ffff:ffff:ffff:ffff:ffff
1442078:8f00::/242078:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1452078:9000::/242078:90ff:ffff:ffff:ffff:ffff:ffff:ffff
1462078:9100::/242078:91ff:ffff:ffff:ffff:ffff:ffff:ffff
1472078:9200::/242078:92ff:ffff:ffff:ffff:ffff:ffff:ffff
1482078:9300::/242078:93ff:ffff:ffff:ffff:ffff:ffff:ffff
1492078:9400::/242078:94ff:ffff:ffff:ffff:ffff:ffff:ffff
1502078:9500::/242078:95ff:ffff:ffff:ffff:ffff:ffff:ffff
1512078:9600::/242078:96ff:ffff:ffff:ffff:ffff:ffff:ffff
1522078:9700::/242078:97ff:ffff:ffff:ffff:ffff:ffff:ffff
1532078:9800::/242078:98ff:ffff:ffff:ffff:ffff:ffff:ffff
1542078:9900::/242078:99ff:ffff:ffff:ffff:ffff:ffff:ffff
1552078:9a00::/242078:9aff:ffff:ffff:ffff:ffff:ffff:ffff
1562078:9b00::/242078:9bff:ffff:ffff:ffff:ffff:ffff:ffff
1572078:9c00::/242078:9cff:ffff:ffff:ffff:ffff:ffff:ffff
1582078:9d00::/242078:9dff:ffff:ffff:ffff:ffff:ffff:ffff
1592078:9e00::/242078:9eff:ffff:ffff:ffff:ffff:ffff:ffff
1602078:9f00::/242078:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1612078:a000::/242078:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
1622078:a100::/242078:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
1632078:a200::/242078:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
1642078:a300::/242078:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
1652078:a400::/242078:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
1662078:a500::/242078:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
1672078:a600::/242078:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
1682078:a700::/242078:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
1692078:a800::/242078:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
1702078:a900::/242078:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
1712078:aa00::/242078:aaff:ffff:ffff:ffff:ffff:ffff:ffff
1722078:ab00::/242078:abff:ffff:ffff:ffff:ffff:ffff:ffff
1732078:ac00::/242078:acff:ffff:ffff:ffff:ffff:ffff:ffff
1742078:ad00::/242078:adff:ffff:ffff:ffff:ffff:ffff:ffff
1752078:ae00::/242078:aeff:ffff:ffff:ffff:ffff:ffff:ffff
1762078:af00::/242078:afff:ffff:ffff:ffff:ffff:ffff:ffff
1772078:b000::/242078:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
1782078:b100::/242078:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
1792078:b200::/242078:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
1802078:b300::/242078:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
1812078:b400::/242078:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
1822078:b500::/242078:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
1832078:b600::/242078:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
1842078:b700::/242078:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
1852078:b800::/242078:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
1862078:b900::/242078:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
1872078:ba00::/242078:baff:ffff:ffff:ffff:ffff:ffff:ffff
1882078:bb00::/242078:bbff:ffff:ffff:ffff:ffff:ffff:ffff
1892078:bc00::/242078:bcff:ffff:ffff:ffff:ffff:ffff:ffff
1902078:bd00::/242078:bdff:ffff:ffff:ffff:ffff:ffff:ffff
1912078:be00::/242078:beff:ffff:ffff:ffff:ffff:ffff:ffff
1922078:bf00::/242078:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1932078:c000::/242078:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
1942078:c100::/242078:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
1952078:c200::/242078:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
1962078:c300::/242078:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
1972078:c400::/242078:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
1982078:c500::/242078:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
1992078:c600::/242078:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
2002078:c700::/242078:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
2012078:c800::/242078:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
2022078:c900::/242078:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
2032078:ca00::/242078:caff:ffff:ffff:ffff:ffff:ffff:ffff
2042078:cb00::/242078:cbff:ffff:ffff:ffff:ffff:ffff:ffff
2052078:cc00::/242078:ccff:ffff:ffff:ffff:ffff:ffff:ffff
2062078:cd00::/242078:cdff:ffff:ffff:ffff:ffff:ffff:ffff
2072078:ce00::/242078:ceff:ffff:ffff:ffff:ffff:ffff:ffff
2082078:cf00::/242078:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2092078:d000::/242078:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
2102078:d100::/242078:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
2112078:d200::/242078:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
2122078:d300::/242078:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
2132078:d400::/242078:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
2142078:d500::/242078:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
2152078:d600::/242078:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
2162078:d700::/242078:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
2172078:d800::/242078:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
2182078:d900::/242078:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
2192078:da00::/242078:daff:ffff:ffff:ffff:ffff:ffff:ffff
2202078:db00::/242078:dbff:ffff:ffff:ffff:ffff:ffff:ffff
2212078:dc00::/242078:dcff:ffff:ffff:ffff:ffff:ffff:ffff
2222078:dd00::/242078:ddff:ffff:ffff:ffff:ffff:ffff:ffff
2232078:de00::/242078:deff:ffff:ffff:ffff:ffff:ffff:ffff
2242078:df00::/242078:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2252078:e000::/242078:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
2262078:e100::/242078:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
2272078:e200::/242078:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
2282078:e300::/242078:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
2292078:e400::/242078:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
2302078:e500::/242078:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
2312078:e600::/242078:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
2322078:e700::/242078:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
2332078:e800::/242078:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
2342078:e900::/242078:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
2352078:ea00::/242078:eaff:ffff:ffff:ffff:ffff:ffff:ffff
2362078:eb00::/242078:ebff:ffff:ffff:ffff:ffff:ffff:ffff
2372078:ec00::/242078:ecff:ffff:ffff:ffff:ffff:ffff:ffff
2382078:ed00::/242078:edff:ffff:ffff:ffff:ffff:ffff:ffff
2392078:ee00::/242078:eeff:ffff:ffff:ffff:ffff:ffff:ffff
2402078:ef00::/242078:efff:ffff:ffff:ffff:ffff:ffff:ffff
2412078:f000::/242078:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
2422078:f100::/242078:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
2432078:f200::/242078:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
2442078:f300::/242078:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
2452078:f400::/242078:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
2462078:f500::/242078:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
2472078:f600::/242078:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
2482078:f700::/242078:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
2492078:f800::/242078:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
2502078:f900::/242078:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
2512078:fa00::/242078:faff:ffff:ffff:ffff:ffff:ffff:ffff
2522078:fb00::/242078:fbff:ffff:ffff:ffff:ffff:ffff:ffff
2532078:fc00::/242078:fcff:ffff:ffff:ffff:ffff:ffff:ffff
2542078:fd00::/242078:fdff:ffff:ffff:ffff:ffff:ffff:ffff
2552078:fe00::/242078:feff:ffff:ffff:ffff:ffff:ffff:ffff
2562078:ff00::/242078: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.