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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/12
Addresses2^116
/64 networks2^52
Network
2690::/12
First address
2690::
Last address
269f:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
83,076,749,736,557,242,056,487,941,267,521,536 (2^116)
/64 networks (LANs)
4,503,599,627,370,496 (2^52)
Full form
2690:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
9.6.2.ip6.arpa
Split into smaller subnets/24
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

2690::/12 makes 4,096 subnets of /24; the first 256 are listed.

Subnets
#SubnetLast address
12690::/242690:ff:ffff:ffff:ffff:ffff:ffff:ffff
22690:100::/242690:1ff:ffff:ffff:ffff:ffff:ffff:ffff
32690:200::/242690:2ff:ffff:ffff:ffff:ffff:ffff:ffff
42690:300::/242690:3ff:ffff:ffff:ffff:ffff:ffff:ffff
52690:400::/242690:4ff:ffff:ffff:ffff:ffff:ffff:ffff
62690:500::/242690:5ff:ffff:ffff:ffff:ffff:ffff:ffff
72690:600::/242690:6ff:ffff:ffff:ffff:ffff:ffff:ffff
82690:700::/242690:7ff:ffff:ffff:ffff:ffff:ffff:ffff
92690:800::/242690:8ff:ffff:ffff:ffff:ffff:ffff:ffff
102690:900::/242690:9ff:ffff:ffff:ffff:ffff:ffff:ffff
112690:a00::/242690:aff:ffff:ffff:ffff:ffff:ffff:ffff
122690:b00::/242690:bff:ffff:ffff:ffff:ffff:ffff:ffff
132690:c00::/242690:cff:ffff:ffff:ffff:ffff:ffff:ffff
142690:d00::/242690:dff:ffff:ffff:ffff:ffff:ffff:ffff
152690:e00::/242690:eff:ffff:ffff:ffff:ffff:ffff:ffff
162690:f00::/242690:fff:ffff:ffff:ffff:ffff:ffff:ffff
172690:1000::/242690:10ff:ffff:ffff:ffff:ffff:ffff:ffff
182690:1100::/242690:11ff:ffff:ffff:ffff:ffff:ffff:ffff
192690:1200::/242690:12ff:ffff:ffff:ffff:ffff:ffff:ffff
202690:1300::/242690:13ff:ffff:ffff:ffff:ffff:ffff:ffff
212690:1400::/242690:14ff:ffff:ffff:ffff:ffff:ffff:ffff
222690:1500::/242690:15ff:ffff:ffff:ffff:ffff:ffff:ffff
232690:1600::/242690:16ff:ffff:ffff:ffff:ffff:ffff:ffff
242690:1700::/242690:17ff:ffff:ffff:ffff:ffff:ffff:ffff
252690:1800::/242690:18ff:ffff:ffff:ffff:ffff:ffff:ffff
262690:1900::/242690:19ff:ffff:ffff:ffff:ffff:ffff:ffff
272690:1a00::/242690:1aff:ffff:ffff:ffff:ffff:ffff:ffff
282690:1b00::/242690:1bff:ffff:ffff:ffff:ffff:ffff:ffff
292690:1c00::/242690:1cff:ffff:ffff:ffff:ffff:ffff:ffff
302690:1d00::/242690:1dff:ffff:ffff:ffff:ffff:ffff:ffff
312690:1e00::/242690:1eff:ffff:ffff:ffff:ffff:ffff:ffff
322690:1f00::/242690:1fff:ffff:ffff:ffff:ffff:ffff:ffff
332690:2000::/242690:20ff:ffff:ffff:ffff:ffff:ffff:ffff
342690:2100::/242690:21ff:ffff:ffff:ffff:ffff:ffff:ffff
352690:2200::/242690:22ff:ffff:ffff:ffff:ffff:ffff:ffff
362690:2300::/242690:23ff:ffff:ffff:ffff:ffff:ffff:ffff
372690:2400::/242690:24ff:ffff:ffff:ffff:ffff:ffff:ffff
382690:2500::/242690:25ff:ffff:ffff:ffff:ffff:ffff:ffff
392690:2600::/242690:26ff:ffff:ffff:ffff:ffff:ffff:ffff
402690:2700::/242690:27ff:ffff:ffff:ffff:ffff:ffff:ffff
412690:2800::/242690:28ff:ffff:ffff:ffff:ffff:ffff:ffff
422690:2900::/242690:29ff:ffff:ffff:ffff:ffff:ffff:ffff
432690:2a00::/242690:2aff:ffff:ffff:ffff:ffff:ffff:ffff
442690:2b00::/242690:2bff:ffff:ffff:ffff:ffff:ffff:ffff
452690:2c00::/242690:2cff:ffff:ffff:ffff:ffff:ffff:ffff
462690:2d00::/242690:2dff:ffff:ffff:ffff:ffff:ffff:ffff
472690:2e00::/242690:2eff:ffff:ffff:ffff:ffff:ffff:ffff
482690:2f00::/242690:2fff:ffff:ffff:ffff:ffff:ffff:ffff
492690:3000::/242690:30ff:ffff:ffff:ffff:ffff:ffff:ffff
502690:3100::/242690:31ff:ffff:ffff:ffff:ffff:ffff:ffff
512690:3200::/242690:32ff:ffff:ffff:ffff:ffff:ffff:ffff
522690:3300::/242690:33ff:ffff:ffff:ffff:ffff:ffff:ffff
532690:3400::/242690:34ff:ffff:ffff:ffff:ffff:ffff:ffff
542690:3500::/242690:35ff:ffff:ffff:ffff:ffff:ffff:ffff
552690:3600::/242690:36ff:ffff:ffff:ffff:ffff:ffff:ffff
562690:3700::/242690:37ff:ffff:ffff:ffff:ffff:ffff:ffff
572690:3800::/242690:38ff:ffff:ffff:ffff:ffff:ffff:ffff
582690:3900::/242690:39ff:ffff:ffff:ffff:ffff:ffff:ffff
592690:3a00::/242690:3aff:ffff:ffff:ffff:ffff:ffff:ffff
602690:3b00::/242690:3bff:ffff:ffff:ffff:ffff:ffff:ffff
612690:3c00::/242690:3cff:ffff:ffff:ffff:ffff:ffff:ffff
622690:3d00::/242690:3dff:ffff:ffff:ffff:ffff:ffff:ffff
632690:3e00::/242690:3eff:ffff:ffff:ffff:ffff:ffff:ffff
642690:3f00::/242690:3fff:ffff:ffff:ffff:ffff:ffff:ffff
652690:4000::/242690:40ff:ffff:ffff:ffff:ffff:ffff:ffff
662690:4100::/242690:41ff:ffff:ffff:ffff:ffff:ffff:ffff
672690:4200::/242690:42ff:ffff:ffff:ffff:ffff:ffff:ffff
682690:4300::/242690:43ff:ffff:ffff:ffff:ffff:ffff:ffff
692690:4400::/242690:44ff:ffff:ffff:ffff:ffff:ffff:ffff
702690:4500::/242690:45ff:ffff:ffff:ffff:ffff:ffff:ffff
712690:4600::/242690:46ff:ffff:ffff:ffff:ffff:ffff:ffff
722690:4700::/242690:47ff:ffff:ffff:ffff:ffff:ffff:ffff
732690:4800::/242690:48ff:ffff:ffff:ffff:ffff:ffff:ffff
742690:4900::/242690:49ff:ffff:ffff:ffff:ffff:ffff:ffff
752690:4a00::/242690:4aff:ffff:ffff:ffff:ffff:ffff:ffff
762690:4b00::/242690:4bff:ffff:ffff:ffff:ffff:ffff:ffff
772690:4c00::/242690:4cff:ffff:ffff:ffff:ffff:ffff:ffff
782690:4d00::/242690:4dff:ffff:ffff:ffff:ffff:ffff:ffff
792690:4e00::/242690:4eff:ffff:ffff:ffff:ffff:ffff:ffff
802690:4f00::/242690:4fff:ffff:ffff:ffff:ffff:ffff:ffff
812690:5000::/242690:50ff:ffff:ffff:ffff:ffff:ffff:ffff
822690:5100::/242690:51ff:ffff:ffff:ffff:ffff:ffff:ffff
832690:5200::/242690:52ff:ffff:ffff:ffff:ffff:ffff:ffff
842690:5300::/242690:53ff:ffff:ffff:ffff:ffff:ffff:ffff
852690:5400::/242690:54ff:ffff:ffff:ffff:ffff:ffff:ffff
862690:5500::/242690:55ff:ffff:ffff:ffff:ffff:ffff:ffff
872690:5600::/242690:56ff:ffff:ffff:ffff:ffff:ffff:ffff
882690:5700::/242690:57ff:ffff:ffff:ffff:ffff:ffff:ffff
892690:5800::/242690:58ff:ffff:ffff:ffff:ffff:ffff:ffff
902690:5900::/242690:59ff:ffff:ffff:ffff:ffff:ffff:ffff
912690:5a00::/242690:5aff:ffff:ffff:ffff:ffff:ffff:ffff
922690:5b00::/242690:5bff:ffff:ffff:ffff:ffff:ffff:ffff
932690:5c00::/242690:5cff:ffff:ffff:ffff:ffff:ffff:ffff
942690:5d00::/242690:5dff:ffff:ffff:ffff:ffff:ffff:ffff
952690:5e00::/242690:5eff:ffff:ffff:ffff:ffff:ffff:ffff
962690:5f00::/242690:5fff:ffff:ffff:ffff:ffff:ffff:ffff
972690:6000::/242690:60ff:ffff:ffff:ffff:ffff:ffff:ffff
982690:6100::/242690:61ff:ffff:ffff:ffff:ffff:ffff:ffff
992690:6200::/242690:62ff:ffff:ffff:ffff:ffff:ffff:ffff
1002690:6300::/242690:63ff:ffff:ffff:ffff:ffff:ffff:ffff
1012690:6400::/242690:64ff:ffff:ffff:ffff:ffff:ffff:ffff
1022690:6500::/242690:65ff:ffff:ffff:ffff:ffff:ffff:ffff
1032690:6600::/242690:66ff:ffff:ffff:ffff:ffff:ffff:ffff
1042690:6700::/242690:67ff:ffff:ffff:ffff:ffff:ffff:ffff
1052690:6800::/242690:68ff:ffff:ffff:ffff:ffff:ffff:ffff
1062690:6900::/242690:69ff:ffff:ffff:ffff:ffff:ffff:ffff
1072690:6a00::/242690:6aff:ffff:ffff:ffff:ffff:ffff:ffff
1082690:6b00::/242690:6bff:ffff:ffff:ffff:ffff:ffff:ffff
1092690:6c00::/242690:6cff:ffff:ffff:ffff:ffff:ffff:ffff
1102690:6d00::/242690:6dff:ffff:ffff:ffff:ffff:ffff:ffff
1112690:6e00::/242690:6eff:ffff:ffff:ffff:ffff:ffff:ffff
1122690:6f00::/242690:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1132690:7000::/242690:70ff:ffff:ffff:ffff:ffff:ffff:ffff
1142690:7100::/242690:71ff:ffff:ffff:ffff:ffff:ffff:ffff
1152690:7200::/242690:72ff:ffff:ffff:ffff:ffff:ffff:ffff
1162690:7300::/242690:73ff:ffff:ffff:ffff:ffff:ffff:ffff
1172690:7400::/242690:74ff:ffff:ffff:ffff:ffff:ffff:ffff
1182690:7500::/242690:75ff:ffff:ffff:ffff:ffff:ffff:ffff
1192690:7600::/242690:76ff:ffff:ffff:ffff:ffff:ffff:ffff
1202690:7700::/242690:77ff:ffff:ffff:ffff:ffff:ffff:ffff
1212690:7800::/242690:78ff:ffff:ffff:ffff:ffff:ffff:ffff
1222690:7900::/242690:79ff:ffff:ffff:ffff:ffff:ffff:ffff
1232690:7a00::/242690:7aff:ffff:ffff:ffff:ffff:ffff:ffff
1242690:7b00::/242690:7bff:ffff:ffff:ffff:ffff:ffff:ffff
1252690:7c00::/242690:7cff:ffff:ffff:ffff:ffff:ffff:ffff
1262690:7d00::/242690:7dff:ffff:ffff:ffff:ffff:ffff:ffff
1272690:7e00::/242690:7eff:ffff:ffff:ffff:ffff:ffff:ffff
1282690:7f00::/242690:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1292690:8000::/242690:80ff:ffff:ffff:ffff:ffff:ffff:ffff
1302690:8100::/242690:81ff:ffff:ffff:ffff:ffff:ffff:ffff
1312690:8200::/242690:82ff:ffff:ffff:ffff:ffff:ffff:ffff
1322690:8300::/242690:83ff:ffff:ffff:ffff:ffff:ffff:ffff
1332690:8400::/242690:84ff:ffff:ffff:ffff:ffff:ffff:ffff
1342690:8500::/242690:85ff:ffff:ffff:ffff:ffff:ffff:ffff
1352690:8600::/242690:86ff:ffff:ffff:ffff:ffff:ffff:ffff
1362690:8700::/242690:87ff:ffff:ffff:ffff:ffff:ffff:ffff
1372690:8800::/242690:88ff:ffff:ffff:ffff:ffff:ffff:ffff
1382690:8900::/242690:89ff:ffff:ffff:ffff:ffff:ffff:ffff
1392690:8a00::/242690:8aff:ffff:ffff:ffff:ffff:ffff:ffff
1402690:8b00::/242690:8bff:ffff:ffff:ffff:ffff:ffff:ffff
1412690:8c00::/242690:8cff:ffff:ffff:ffff:ffff:ffff:ffff
1422690:8d00::/242690:8dff:ffff:ffff:ffff:ffff:ffff:ffff
1432690:8e00::/242690:8eff:ffff:ffff:ffff:ffff:ffff:ffff
1442690:8f00::/242690:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1452690:9000::/242690:90ff:ffff:ffff:ffff:ffff:ffff:ffff
1462690:9100::/242690:91ff:ffff:ffff:ffff:ffff:ffff:ffff
1472690:9200::/242690:92ff:ffff:ffff:ffff:ffff:ffff:ffff
1482690:9300::/242690:93ff:ffff:ffff:ffff:ffff:ffff:ffff
1492690:9400::/242690:94ff:ffff:ffff:ffff:ffff:ffff:ffff
1502690:9500::/242690:95ff:ffff:ffff:ffff:ffff:ffff:ffff
1512690:9600::/242690:96ff:ffff:ffff:ffff:ffff:ffff:ffff
1522690:9700::/242690:97ff:ffff:ffff:ffff:ffff:ffff:ffff
1532690:9800::/242690:98ff:ffff:ffff:ffff:ffff:ffff:ffff
1542690:9900::/242690:99ff:ffff:ffff:ffff:ffff:ffff:ffff
1552690:9a00::/242690:9aff:ffff:ffff:ffff:ffff:ffff:ffff
1562690:9b00::/242690:9bff:ffff:ffff:ffff:ffff:ffff:ffff
1572690:9c00::/242690:9cff:ffff:ffff:ffff:ffff:ffff:ffff
1582690:9d00::/242690:9dff:ffff:ffff:ffff:ffff:ffff:ffff
1592690:9e00::/242690:9eff:ffff:ffff:ffff:ffff:ffff:ffff
1602690:9f00::/242690:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1612690:a000::/242690:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
1622690:a100::/242690:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
1632690:a200::/242690:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
1642690:a300::/242690:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
1652690:a400::/242690:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
1662690:a500::/242690:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
1672690:a600::/242690:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
1682690:a700::/242690:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
1692690:a800::/242690:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
1702690:a900::/242690:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
1712690:aa00::/242690:aaff:ffff:ffff:ffff:ffff:ffff:ffff
1722690:ab00::/242690:abff:ffff:ffff:ffff:ffff:ffff:ffff
1732690:ac00::/242690:acff:ffff:ffff:ffff:ffff:ffff:ffff
1742690:ad00::/242690:adff:ffff:ffff:ffff:ffff:ffff:ffff
1752690:ae00::/242690:aeff:ffff:ffff:ffff:ffff:ffff:ffff
1762690:af00::/242690:afff:ffff:ffff:ffff:ffff:ffff:ffff
1772690:b000::/242690:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
1782690:b100::/242690:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
1792690:b200::/242690:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
1802690:b300::/242690:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
1812690:b400::/242690:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
1822690:b500::/242690:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
1832690:b600::/242690:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
1842690:b700::/242690:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
1852690:b800::/242690:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
1862690:b900::/242690:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
1872690:ba00::/242690:baff:ffff:ffff:ffff:ffff:ffff:ffff
1882690:bb00::/242690:bbff:ffff:ffff:ffff:ffff:ffff:ffff
1892690:bc00::/242690:bcff:ffff:ffff:ffff:ffff:ffff:ffff
1902690:bd00::/242690:bdff:ffff:ffff:ffff:ffff:ffff:ffff
1912690:be00::/242690:beff:ffff:ffff:ffff:ffff:ffff:ffff
1922690:bf00::/242690:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1932690:c000::/242690:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
1942690:c100::/242690:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
1952690:c200::/242690:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
1962690:c300::/242690:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
1972690:c400::/242690:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
1982690:c500::/242690:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
1992690:c600::/242690:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
2002690:c700::/242690:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
2012690:c800::/242690:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
2022690:c900::/242690:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
2032690:ca00::/242690:caff:ffff:ffff:ffff:ffff:ffff:ffff
2042690:cb00::/242690:cbff:ffff:ffff:ffff:ffff:ffff:ffff
2052690:cc00::/242690:ccff:ffff:ffff:ffff:ffff:ffff:ffff
2062690:cd00::/242690:cdff:ffff:ffff:ffff:ffff:ffff:ffff
2072690:ce00::/242690:ceff:ffff:ffff:ffff:ffff:ffff:ffff
2082690:cf00::/242690:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2092690:d000::/242690:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
2102690:d100::/242690:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
2112690:d200::/242690:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
2122690:d300::/242690:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
2132690:d400::/242690:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
2142690:d500::/242690:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
2152690:d600::/242690:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
2162690:d700::/242690:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
2172690:d800::/242690:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
2182690:d900::/242690:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
2192690:da00::/242690:daff:ffff:ffff:ffff:ffff:ffff:ffff
2202690:db00::/242690:dbff:ffff:ffff:ffff:ffff:ffff:ffff
2212690:dc00::/242690:dcff:ffff:ffff:ffff:ffff:ffff:ffff
2222690:dd00::/242690:ddff:ffff:ffff:ffff:ffff:ffff:ffff
2232690:de00::/242690:deff:ffff:ffff:ffff:ffff:ffff:ffff
2242690:df00::/242690:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2252690:e000::/242690:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
2262690:e100::/242690:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
2272690:e200::/242690:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
2282690:e300::/242690:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
2292690:e400::/242690:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
2302690:e500::/242690:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
2312690:e600::/242690:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
2322690:e700::/242690:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
2332690:e800::/242690:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
2342690:e900::/242690:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
2352690:ea00::/242690:eaff:ffff:ffff:ffff:ffff:ffff:ffff
2362690:eb00::/242690:ebff:ffff:ffff:ffff:ffff:ffff:ffff
2372690:ec00::/242690:ecff:ffff:ffff:ffff:ffff:ffff:ffff
2382690:ed00::/242690:edff:ffff:ffff:ffff:ffff:ffff:ffff
2392690:ee00::/242690:eeff:ffff:ffff:ffff:ffff:ffff:ffff
2402690:ef00::/242690:efff:ffff:ffff:ffff:ffff:ffff:ffff
2412690:f000::/242690:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
2422690:f100::/242690:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
2432690:f200::/242690:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
2442690:f300::/242690:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
2452690:f400::/242690:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
2462690:f500::/242690:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
2472690:f600::/242690:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
2482690:f700::/242690:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
2492690:f800::/242690:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
2502690:f900::/242690:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
2512690:fa00::/242690:faff:ffff:ffff:ffff:ffff:ffff:ffff
2522690:fb00::/242690:fbff:ffff:ffff:ffff:ffff:ffff:ffff
2532690:fc00::/242690:fcff:ffff:ffff:ffff:ffff:ffff:ffff
2542690:fd00::/242690:fdff:ffff:ffff:ffff:ffff:ffff:ffff
2552690:fe00::/242690:feff:ffff:ffff:ffff:ffff:ffff:ffff
2562690:ff00::/242690: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.