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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
2750::/12
First address
2750::
Last address
275f: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
2750:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
5.7.2.ip6.arpa
Split into smaller subnets/24
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

2750::/12 makes 4,096 subnets of /24; the first 256 are listed.

Subnets
#SubnetLast address
12750::/242750:ff:ffff:ffff:ffff:ffff:ffff:ffff
22750:100::/242750:1ff:ffff:ffff:ffff:ffff:ffff:ffff
32750:200::/242750:2ff:ffff:ffff:ffff:ffff:ffff:ffff
42750:300::/242750:3ff:ffff:ffff:ffff:ffff:ffff:ffff
52750:400::/242750:4ff:ffff:ffff:ffff:ffff:ffff:ffff
62750:500::/242750:5ff:ffff:ffff:ffff:ffff:ffff:ffff
72750:600::/242750:6ff:ffff:ffff:ffff:ffff:ffff:ffff
82750:700::/242750:7ff:ffff:ffff:ffff:ffff:ffff:ffff
92750:800::/242750:8ff:ffff:ffff:ffff:ffff:ffff:ffff
102750:900::/242750:9ff:ffff:ffff:ffff:ffff:ffff:ffff
112750:a00::/242750:aff:ffff:ffff:ffff:ffff:ffff:ffff
122750:b00::/242750:bff:ffff:ffff:ffff:ffff:ffff:ffff
132750:c00::/242750:cff:ffff:ffff:ffff:ffff:ffff:ffff
142750:d00::/242750:dff:ffff:ffff:ffff:ffff:ffff:ffff
152750:e00::/242750:eff:ffff:ffff:ffff:ffff:ffff:ffff
162750:f00::/242750:fff:ffff:ffff:ffff:ffff:ffff:ffff
172750:1000::/242750:10ff:ffff:ffff:ffff:ffff:ffff:ffff
182750:1100::/242750:11ff:ffff:ffff:ffff:ffff:ffff:ffff
192750:1200::/242750:12ff:ffff:ffff:ffff:ffff:ffff:ffff
202750:1300::/242750:13ff:ffff:ffff:ffff:ffff:ffff:ffff
212750:1400::/242750:14ff:ffff:ffff:ffff:ffff:ffff:ffff
222750:1500::/242750:15ff:ffff:ffff:ffff:ffff:ffff:ffff
232750:1600::/242750:16ff:ffff:ffff:ffff:ffff:ffff:ffff
242750:1700::/242750:17ff:ffff:ffff:ffff:ffff:ffff:ffff
252750:1800::/242750:18ff:ffff:ffff:ffff:ffff:ffff:ffff
262750:1900::/242750:19ff:ffff:ffff:ffff:ffff:ffff:ffff
272750:1a00::/242750:1aff:ffff:ffff:ffff:ffff:ffff:ffff
282750:1b00::/242750:1bff:ffff:ffff:ffff:ffff:ffff:ffff
292750:1c00::/242750:1cff:ffff:ffff:ffff:ffff:ffff:ffff
302750:1d00::/242750:1dff:ffff:ffff:ffff:ffff:ffff:ffff
312750:1e00::/242750:1eff:ffff:ffff:ffff:ffff:ffff:ffff
322750:1f00::/242750:1fff:ffff:ffff:ffff:ffff:ffff:ffff
332750:2000::/242750:20ff:ffff:ffff:ffff:ffff:ffff:ffff
342750:2100::/242750:21ff:ffff:ffff:ffff:ffff:ffff:ffff
352750:2200::/242750:22ff:ffff:ffff:ffff:ffff:ffff:ffff
362750:2300::/242750:23ff:ffff:ffff:ffff:ffff:ffff:ffff
372750:2400::/242750:24ff:ffff:ffff:ffff:ffff:ffff:ffff
382750:2500::/242750:25ff:ffff:ffff:ffff:ffff:ffff:ffff
392750:2600::/242750:26ff:ffff:ffff:ffff:ffff:ffff:ffff
402750:2700::/242750:27ff:ffff:ffff:ffff:ffff:ffff:ffff
412750:2800::/242750:28ff:ffff:ffff:ffff:ffff:ffff:ffff
422750:2900::/242750:29ff:ffff:ffff:ffff:ffff:ffff:ffff
432750:2a00::/242750:2aff:ffff:ffff:ffff:ffff:ffff:ffff
442750:2b00::/242750:2bff:ffff:ffff:ffff:ffff:ffff:ffff
452750:2c00::/242750:2cff:ffff:ffff:ffff:ffff:ffff:ffff
462750:2d00::/242750:2dff:ffff:ffff:ffff:ffff:ffff:ffff
472750:2e00::/242750:2eff:ffff:ffff:ffff:ffff:ffff:ffff
482750:2f00::/242750:2fff:ffff:ffff:ffff:ffff:ffff:ffff
492750:3000::/242750:30ff:ffff:ffff:ffff:ffff:ffff:ffff
502750:3100::/242750:31ff:ffff:ffff:ffff:ffff:ffff:ffff
512750:3200::/242750:32ff:ffff:ffff:ffff:ffff:ffff:ffff
522750:3300::/242750:33ff:ffff:ffff:ffff:ffff:ffff:ffff
532750:3400::/242750:34ff:ffff:ffff:ffff:ffff:ffff:ffff
542750:3500::/242750:35ff:ffff:ffff:ffff:ffff:ffff:ffff
552750:3600::/242750:36ff:ffff:ffff:ffff:ffff:ffff:ffff
562750:3700::/242750:37ff:ffff:ffff:ffff:ffff:ffff:ffff
572750:3800::/242750:38ff:ffff:ffff:ffff:ffff:ffff:ffff
582750:3900::/242750:39ff:ffff:ffff:ffff:ffff:ffff:ffff
592750:3a00::/242750:3aff:ffff:ffff:ffff:ffff:ffff:ffff
602750:3b00::/242750:3bff:ffff:ffff:ffff:ffff:ffff:ffff
612750:3c00::/242750:3cff:ffff:ffff:ffff:ffff:ffff:ffff
622750:3d00::/242750:3dff:ffff:ffff:ffff:ffff:ffff:ffff
632750:3e00::/242750:3eff:ffff:ffff:ffff:ffff:ffff:ffff
642750:3f00::/242750:3fff:ffff:ffff:ffff:ffff:ffff:ffff
652750:4000::/242750:40ff:ffff:ffff:ffff:ffff:ffff:ffff
662750:4100::/242750:41ff:ffff:ffff:ffff:ffff:ffff:ffff
672750:4200::/242750:42ff:ffff:ffff:ffff:ffff:ffff:ffff
682750:4300::/242750:43ff:ffff:ffff:ffff:ffff:ffff:ffff
692750:4400::/242750:44ff:ffff:ffff:ffff:ffff:ffff:ffff
702750:4500::/242750:45ff:ffff:ffff:ffff:ffff:ffff:ffff
712750:4600::/242750:46ff:ffff:ffff:ffff:ffff:ffff:ffff
722750:4700::/242750:47ff:ffff:ffff:ffff:ffff:ffff:ffff
732750:4800::/242750:48ff:ffff:ffff:ffff:ffff:ffff:ffff
742750:4900::/242750:49ff:ffff:ffff:ffff:ffff:ffff:ffff
752750:4a00::/242750:4aff:ffff:ffff:ffff:ffff:ffff:ffff
762750:4b00::/242750:4bff:ffff:ffff:ffff:ffff:ffff:ffff
772750:4c00::/242750:4cff:ffff:ffff:ffff:ffff:ffff:ffff
782750:4d00::/242750:4dff:ffff:ffff:ffff:ffff:ffff:ffff
792750:4e00::/242750:4eff:ffff:ffff:ffff:ffff:ffff:ffff
802750:4f00::/242750:4fff:ffff:ffff:ffff:ffff:ffff:ffff
812750:5000::/242750:50ff:ffff:ffff:ffff:ffff:ffff:ffff
822750:5100::/242750:51ff:ffff:ffff:ffff:ffff:ffff:ffff
832750:5200::/242750:52ff:ffff:ffff:ffff:ffff:ffff:ffff
842750:5300::/242750:53ff:ffff:ffff:ffff:ffff:ffff:ffff
852750:5400::/242750:54ff:ffff:ffff:ffff:ffff:ffff:ffff
862750:5500::/242750:55ff:ffff:ffff:ffff:ffff:ffff:ffff
872750:5600::/242750:56ff:ffff:ffff:ffff:ffff:ffff:ffff
882750:5700::/242750:57ff:ffff:ffff:ffff:ffff:ffff:ffff
892750:5800::/242750:58ff:ffff:ffff:ffff:ffff:ffff:ffff
902750:5900::/242750:59ff:ffff:ffff:ffff:ffff:ffff:ffff
912750:5a00::/242750:5aff:ffff:ffff:ffff:ffff:ffff:ffff
922750:5b00::/242750:5bff:ffff:ffff:ffff:ffff:ffff:ffff
932750:5c00::/242750:5cff:ffff:ffff:ffff:ffff:ffff:ffff
942750:5d00::/242750:5dff:ffff:ffff:ffff:ffff:ffff:ffff
952750:5e00::/242750:5eff:ffff:ffff:ffff:ffff:ffff:ffff
962750:5f00::/242750:5fff:ffff:ffff:ffff:ffff:ffff:ffff
972750:6000::/242750:60ff:ffff:ffff:ffff:ffff:ffff:ffff
982750:6100::/242750:61ff:ffff:ffff:ffff:ffff:ffff:ffff
992750:6200::/242750:62ff:ffff:ffff:ffff:ffff:ffff:ffff
1002750:6300::/242750:63ff:ffff:ffff:ffff:ffff:ffff:ffff
1012750:6400::/242750:64ff:ffff:ffff:ffff:ffff:ffff:ffff
1022750:6500::/242750:65ff:ffff:ffff:ffff:ffff:ffff:ffff
1032750:6600::/242750:66ff:ffff:ffff:ffff:ffff:ffff:ffff
1042750:6700::/242750:67ff:ffff:ffff:ffff:ffff:ffff:ffff
1052750:6800::/242750:68ff:ffff:ffff:ffff:ffff:ffff:ffff
1062750:6900::/242750:69ff:ffff:ffff:ffff:ffff:ffff:ffff
1072750:6a00::/242750:6aff:ffff:ffff:ffff:ffff:ffff:ffff
1082750:6b00::/242750:6bff:ffff:ffff:ffff:ffff:ffff:ffff
1092750:6c00::/242750:6cff:ffff:ffff:ffff:ffff:ffff:ffff
1102750:6d00::/242750:6dff:ffff:ffff:ffff:ffff:ffff:ffff
1112750:6e00::/242750:6eff:ffff:ffff:ffff:ffff:ffff:ffff
1122750:6f00::/242750:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1132750:7000::/242750:70ff:ffff:ffff:ffff:ffff:ffff:ffff
1142750:7100::/242750:71ff:ffff:ffff:ffff:ffff:ffff:ffff
1152750:7200::/242750:72ff:ffff:ffff:ffff:ffff:ffff:ffff
1162750:7300::/242750:73ff:ffff:ffff:ffff:ffff:ffff:ffff
1172750:7400::/242750:74ff:ffff:ffff:ffff:ffff:ffff:ffff
1182750:7500::/242750:75ff:ffff:ffff:ffff:ffff:ffff:ffff
1192750:7600::/242750:76ff:ffff:ffff:ffff:ffff:ffff:ffff
1202750:7700::/242750:77ff:ffff:ffff:ffff:ffff:ffff:ffff
1212750:7800::/242750:78ff:ffff:ffff:ffff:ffff:ffff:ffff
1222750:7900::/242750:79ff:ffff:ffff:ffff:ffff:ffff:ffff
1232750:7a00::/242750:7aff:ffff:ffff:ffff:ffff:ffff:ffff
1242750:7b00::/242750:7bff:ffff:ffff:ffff:ffff:ffff:ffff
1252750:7c00::/242750:7cff:ffff:ffff:ffff:ffff:ffff:ffff
1262750:7d00::/242750:7dff:ffff:ffff:ffff:ffff:ffff:ffff
1272750:7e00::/242750:7eff:ffff:ffff:ffff:ffff:ffff:ffff
1282750:7f00::/242750:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1292750:8000::/242750:80ff:ffff:ffff:ffff:ffff:ffff:ffff
1302750:8100::/242750:81ff:ffff:ffff:ffff:ffff:ffff:ffff
1312750:8200::/242750:82ff:ffff:ffff:ffff:ffff:ffff:ffff
1322750:8300::/242750:83ff:ffff:ffff:ffff:ffff:ffff:ffff
1332750:8400::/242750:84ff:ffff:ffff:ffff:ffff:ffff:ffff
1342750:8500::/242750:85ff:ffff:ffff:ffff:ffff:ffff:ffff
1352750:8600::/242750:86ff:ffff:ffff:ffff:ffff:ffff:ffff
1362750:8700::/242750:87ff:ffff:ffff:ffff:ffff:ffff:ffff
1372750:8800::/242750:88ff:ffff:ffff:ffff:ffff:ffff:ffff
1382750:8900::/242750:89ff:ffff:ffff:ffff:ffff:ffff:ffff
1392750:8a00::/242750:8aff:ffff:ffff:ffff:ffff:ffff:ffff
1402750:8b00::/242750:8bff:ffff:ffff:ffff:ffff:ffff:ffff
1412750:8c00::/242750:8cff:ffff:ffff:ffff:ffff:ffff:ffff
1422750:8d00::/242750:8dff:ffff:ffff:ffff:ffff:ffff:ffff
1432750:8e00::/242750:8eff:ffff:ffff:ffff:ffff:ffff:ffff
1442750:8f00::/242750:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1452750:9000::/242750:90ff:ffff:ffff:ffff:ffff:ffff:ffff
1462750:9100::/242750:91ff:ffff:ffff:ffff:ffff:ffff:ffff
1472750:9200::/242750:92ff:ffff:ffff:ffff:ffff:ffff:ffff
1482750:9300::/242750:93ff:ffff:ffff:ffff:ffff:ffff:ffff
1492750:9400::/242750:94ff:ffff:ffff:ffff:ffff:ffff:ffff
1502750:9500::/242750:95ff:ffff:ffff:ffff:ffff:ffff:ffff
1512750:9600::/242750:96ff:ffff:ffff:ffff:ffff:ffff:ffff
1522750:9700::/242750:97ff:ffff:ffff:ffff:ffff:ffff:ffff
1532750:9800::/242750:98ff:ffff:ffff:ffff:ffff:ffff:ffff
1542750:9900::/242750:99ff:ffff:ffff:ffff:ffff:ffff:ffff
1552750:9a00::/242750:9aff:ffff:ffff:ffff:ffff:ffff:ffff
1562750:9b00::/242750:9bff:ffff:ffff:ffff:ffff:ffff:ffff
1572750:9c00::/242750:9cff:ffff:ffff:ffff:ffff:ffff:ffff
1582750:9d00::/242750:9dff:ffff:ffff:ffff:ffff:ffff:ffff
1592750:9e00::/242750:9eff:ffff:ffff:ffff:ffff:ffff:ffff
1602750:9f00::/242750:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1612750:a000::/242750:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
1622750:a100::/242750:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
1632750:a200::/242750:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
1642750:a300::/242750:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
1652750:a400::/242750:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
1662750:a500::/242750:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
1672750:a600::/242750:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
1682750:a700::/242750:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
1692750:a800::/242750:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
1702750:a900::/242750:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
1712750:aa00::/242750:aaff:ffff:ffff:ffff:ffff:ffff:ffff
1722750:ab00::/242750:abff:ffff:ffff:ffff:ffff:ffff:ffff
1732750:ac00::/242750:acff:ffff:ffff:ffff:ffff:ffff:ffff
1742750:ad00::/242750:adff:ffff:ffff:ffff:ffff:ffff:ffff
1752750:ae00::/242750:aeff:ffff:ffff:ffff:ffff:ffff:ffff
1762750:af00::/242750:afff:ffff:ffff:ffff:ffff:ffff:ffff
1772750:b000::/242750:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
1782750:b100::/242750:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
1792750:b200::/242750:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
1802750:b300::/242750:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
1812750:b400::/242750:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
1822750:b500::/242750:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
1832750:b600::/242750:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
1842750:b700::/242750:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
1852750:b800::/242750:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
1862750:b900::/242750:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
1872750:ba00::/242750:baff:ffff:ffff:ffff:ffff:ffff:ffff
1882750:bb00::/242750:bbff:ffff:ffff:ffff:ffff:ffff:ffff
1892750:bc00::/242750:bcff:ffff:ffff:ffff:ffff:ffff:ffff
1902750:bd00::/242750:bdff:ffff:ffff:ffff:ffff:ffff:ffff
1912750:be00::/242750:beff:ffff:ffff:ffff:ffff:ffff:ffff
1922750:bf00::/242750:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1932750:c000::/242750:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
1942750:c100::/242750:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
1952750:c200::/242750:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
1962750:c300::/242750:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
1972750:c400::/242750:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
1982750:c500::/242750:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
1992750:c600::/242750:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
2002750:c700::/242750:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
2012750:c800::/242750:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
2022750:c900::/242750:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
2032750:ca00::/242750:caff:ffff:ffff:ffff:ffff:ffff:ffff
2042750:cb00::/242750:cbff:ffff:ffff:ffff:ffff:ffff:ffff
2052750:cc00::/242750:ccff:ffff:ffff:ffff:ffff:ffff:ffff
2062750:cd00::/242750:cdff:ffff:ffff:ffff:ffff:ffff:ffff
2072750:ce00::/242750:ceff:ffff:ffff:ffff:ffff:ffff:ffff
2082750:cf00::/242750:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2092750:d000::/242750:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
2102750:d100::/242750:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
2112750:d200::/242750:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
2122750:d300::/242750:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
2132750:d400::/242750:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
2142750:d500::/242750:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
2152750:d600::/242750:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
2162750:d700::/242750:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
2172750:d800::/242750:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
2182750:d900::/242750:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
2192750:da00::/242750:daff:ffff:ffff:ffff:ffff:ffff:ffff
2202750:db00::/242750:dbff:ffff:ffff:ffff:ffff:ffff:ffff
2212750:dc00::/242750:dcff:ffff:ffff:ffff:ffff:ffff:ffff
2222750:dd00::/242750:ddff:ffff:ffff:ffff:ffff:ffff:ffff
2232750:de00::/242750:deff:ffff:ffff:ffff:ffff:ffff:ffff
2242750:df00::/242750:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2252750:e000::/242750:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
2262750:e100::/242750:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
2272750:e200::/242750:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
2282750:e300::/242750:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
2292750:e400::/242750:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
2302750:e500::/242750:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
2312750:e600::/242750:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
2322750:e700::/242750:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
2332750:e800::/242750:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
2342750:e900::/242750:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
2352750:ea00::/242750:eaff:ffff:ffff:ffff:ffff:ffff:ffff
2362750:eb00::/242750:ebff:ffff:ffff:ffff:ffff:ffff:ffff
2372750:ec00::/242750:ecff:ffff:ffff:ffff:ffff:ffff:ffff
2382750:ed00::/242750:edff:ffff:ffff:ffff:ffff:ffff:ffff
2392750:ee00::/242750:eeff:ffff:ffff:ffff:ffff:ffff:ffff
2402750:ef00::/242750:efff:ffff:ffff:ffff:ffff:ffff:ffff
2412750:f000::/242750:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
2422750:f100::/242750:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
2432750:f200::/242750:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
2442750:f300::/242750:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
2452750:f400::/242750:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
2462750:f500::/242750:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
2472750:f600::/242750:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
2482750:f700::/242750:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
2492750:f800::/242750:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
2502750:f900::/242750:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
2512750:fa00::/242750:faff:ffff:ffff:ffff:ffff:ffff:ffff
2522750:fb00::/242750:fbff:ffff:ffff:ffff:ffff:ffff:ffff
2532750:fc00::/242750:fcff:ffff:ffff:ffff:ffff:ffff:ffff
2542750:fd00::/242750:fdff:ffff:ffff:ffff:ffff:ffff:ffff
2552750:fe00::/242750:feff:ffff:ffff:ffff:ffff:ffff:ffff
2562750:ff00::/242750: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.