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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
3298::/16
First address
3298::
Last address
3298: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
3298:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
8.9.2.3.ip6.arpa
Split into smaller subnets/24
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

3298::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
13298::/243298:ff:ffff:ffff:ffff:ffff:ffff:ffff
23298:100::/243298:1ff:ffff:ffff:ffff:ffff:ffff:ffff
33298:200::/243298:2ff:ffff:ffff:ffff:ffff:ffff:ffff
43298:300::/243298:3ff:ffff:ffff:ffff:ffff:ffff:ffff
53298:400::/243298:4ff:ffff:ffff:ffff:ffff:ffff:ffff
63298:500::/243298:5ff:ffff:ffff:ffff:ffff:ffff:ffff
73298:600::/243298:6ff:ffff:ffff:ffff:ffff:ffff:ffff
83298:700::/243298:7ff:ffff:ffff:ffff:ffff:ffff:ffff
93298:800::/243298:8ff:ffff:ffff:ffff:ffff:ffff:ffff
103298:900::/243298:9ff:ffff:ffff:ffff:ffff:ffff:ffff
113298:a00::/243298:aff:ffff:ffff:ffff:ffff:ffff:ffff
123298:b00::/243298:bff:ffff:ffff:ffff:ffff:ffff:ffff
133298:c00::/243298:cff:ffff:ffff:ffff:ffff:ffff:ffff
143298:d00::/243298:dff:ffff:ffff:ffff:ffff:ffff:ffff
153298:e00::/243298:eff:ffff:ffff:ffff:ffff:ffff:ffff
163298:f00::/243298:fff:ffff:ffff:ffff:ffff:ffff:ffff
173298:1000::/243298:10ff:ffff:ffff:ffff:ffff:ffff:ffff
183298:1100::/243298:11ff:ffff:ffff:ffff:ffff:ffff:ffff
193298:1200::/243298:12ff:ffff:ffff:ffff:ffff:ffff:ffff
203298:1300::/243298:13ff:ffff:ffff:ffff:ffff:ffff:ffff
213298:1400::/243298:14ff:ffff:ffff:ffff:ffff:ffff:ffff
223298:1500::/243298:15ff:ffff:ffff:ffff:ffff:ffff:ffff
233298:1600::/243298:16ff:ffff:ffff:ffff:ffff:ffff:ffff
243298:1700::/243298:17ff:ffff:ffff:ffff:ffff:ffff:ffff
253298:1800::/243298:18ff:ffff:ffff:ffff:ffff:ffff:ffff
263298:1900::/243298:19ff:ffff:ffff:ffff:ffff:ffff:ffff
273298:1a00::/243298:1aff:ffff:ffff:ffff:ffff:ffff:ffff
283298:1b00::/243298:1bff:ffff:ffff:ffff:ffff:ffff:ffff
293298:1c00::/243298:1cff:ffff:ffff:ffff:ffff:ffff:ffff
303298:1d00::/243298:1dff:ffff:ffff:ffff:ffff:ffff:ffff
313298:1e00::/243298:1eff:ffff:ffff:ffff:ffff:ffff:ffff
323298:1f00::/243298:1fff:ffff:ffff:ffff:ffff:ffff:ffff
333298:2000::/243298:20ff:ffff:ffff:ffff:ffff:ffff:ffff
343298:2100::/243298:21ff:ffff:ffff:ffff:ffff:ffff:ffff
353298:2200::/243298:22ff:ffff:ffff:ffff:ffff:ffff:ffff
363298:2300::/243298:23ff:ffff:ffff:ffff:ffff:ffff:ffff
373298:2400::/243298:24ff:ffff:ffff:ffff:ffff:ffff:ffff
383298:2500::/243298:25ff:ffff:ffff:ffff:ffff:ffff:ffff
393298:2600::/243298:26ff:ffff:ffff:ffff:ffff:ffff:ffff
403298:2700::/243298:27ff:ffff:ffff:ffff:ffff:ffff:ffff
413298:2800::/243298:28ff:ffff:ffff:ffff:ffff:ffff:ffff
423298:2900::/243298:29ff:ffff:ffff:ffff:ffff:ffff:ffff
433298:2a00::/243298:2aff:ffff:ffff:ffff:ffff:ffff:ffff
443298:2b00::/243298:2bff:ffff:ffff:ffff:ffff:ffff:ffff
453298:2c00::/243298:2cff:ffff:ffff:ffff:ffff:ffff:ffff
463298:2d00::/243298:2dff:ffff:ffff:ffff:ffff:ffff:ffff
473298:2e00::/243298:2eff:ffff:ffff:ffff:ffff:ffff:ffff
483298:2f00::/243298:2fff:ffff:ffff:ffff:ffff:ffff:ffff
493298:3000::/243298:30ff:ffff:ffff:ffff:ffff:ffff:ffff
503298:3100::/243298:31ff:ffff:ffff:ffff:ffff:ffff:ffff
513298:3200::/243298:32ff:ffff:ffff:ffff:ffff:ffff:ffff
523298:3300::/243298:33ff:ffff:ffff:ffff:ffff:ffff:ffff
533298:3400::/243298:34ff:ffff:ffff:ffff:ffff:ffff:ffff
543298:3500::/243298:35ff:ffff:ffff:ffff:ffff:ffff:ffff
553298:3600::/243298:36ff:ffff:ffff:ffff:ffff:ffff:ffff
563298:3700::/243298:37ff:ffff:ffff:ffff:ffff:ffff:ffff
573298:3800::/243298:38ff:ffff:ffff:ffff:ffff:ffff:ffff
583298:3900::/243298:39ff:ffff:ffff:ffff:ffff:ffff:ffff
593298:3a00::/243298:3aff:ffff:ffff:ffff:ffff:ffff:ffff
603298:3b00::/243298:3bff:ffff:ffff:ffff:ffff:ffff:ffff
613298:3c00::/243298:3cff:ffff:ffff:ffff:ffff:ffff:ffff
623298:3d00::/243298:3dff:ffff:ffff:ffff:ffff:ffff:ffff
633298:3e00::/243298:3eff:ffff:ffff:ffff:ffff:ffff:ffff
643298:3f00::/243298:3fff:ffff:ffff:ffff:ffff:ffff:ffff
653298:4000::/243298:40ff:ffff:ffff:ffff:ffff:ffff:ffff
663298:4100::/243298:41ff:ffff:ffff:ffff:ffff:ffff:ffff
673298:4200::/243298:42ff:ffff:ffff:ffff:ffff:ffff:ffff
683298:4300::/243298:43ff:ffff:ffff:ffff:ffff:ffff:ffff
693298:4400::/243298:44ff:ffff:ffff:ffff:ffff:ffff:ffff
703298:4500::/243298:45ff:ffff:ffff:ffff:ffff:ffff:ffff
713298:4600::/243298:46ff:ffff:ffff:ffff:ffff:ffff:ffff
723298:4700::/243298:47ff:ffff:ffff:ffff:ffff:ffff:ffff
733298:4800::/243298:48ff:ffff:ffff:ffff:ffff:ffff:ffff
743298:4900::/243298:49ff:ffff:ffff:ffff:ffff:ffff:ffff
753298:4a00::/243298:4aff:ffff:ffff:ffff:ffff:ffff:ffff
763298:4b00::/243298:4bff:ffff:ffff:ffff:ffff:ffff:ffff
773298:4c00::/243298:4cff:ffff:ffff:ffff:ffff:ffff:ffff
783298:4d00::/243298:4dff:ffff:ffff:ffff:ffff:ffff:ffff
793298:4e00::/243298:4eff:ffff:ffff:ffff:ffff:ffff:ffff
803298:4f00::/243298:4fff:ffff:ffff:ffff:ffff:ffff:ffff
813298:5000::/243298:50ff:ffff:ffff:ffff:ffff:ffff:ffff
823298:5100::/243298:51ff:ffff:ffff:ffff:ffff:ffff:ffff
833298:5200::/243298:52ff:ffff:ffff:ffff:ffff:ffff:ffff
843298:5300::/243298:53ff:ffff:ffff:ffff:ffff:ffff:ffff
853298:5400::/243298:54ff:ffff:ffff:ffff:ffff:ffff:ffff
863298:5500::/243298:55ff:ffff:ffff:ffff:ffff:ffff:ffff
873298:5600::/243298:56ff:ffff:ffff:ffff:ffff:ffff:ffff
883298:5700::/243298:57ff:ffff:ffff:ffff:ffff:ffff:ffff
893298:5800::/243298:58ff:ffff:ffff:ffff:ffff:ffff:ffff
903298:5900::/243298:59ff:ffff:ffff:ffff:ffff:ffff:ffff
913298:5a00::/243298:5aff:ffff:ffff:ffff:ffff:ffff:ffff
923298:5b00::/243298:5bff:ffff:ffff:ffff:ffff:ffff:ffff
933298:5c00::/243298:5cff:ffff:ffff:ffff:ffff:ffff:ffff
943298:5d00::/243298:5dff:ffff:ffff:ffff:ffff:ffff:ffff
953298:5e00::/243298:5eff:ffff:ffff:ffff:ffff:ffff:ffff
963298:5f00::/243298:5fff:ffff:ffff:ffff:ffff:ffff:ffff
973298:6000::/243298:60ff:ffff:ffff:ffff:ffff:ffff:ffff
983298:6100::/243298:61ff:ffff:ffff:ffff:ffff:ffff:ffff
993298:6200::/243298:62ff:ffff:ffff:ffff:ffff:ffff:ffff
1003298:6300::/243298:63ff:ffff:ffff:ffff:ffff:ffff:ffff
1013298:6400::/243298:64ff:ffff:ffff:ffff:ffff:ffff:ffff
1023298:6500::/243298:65ff:ffff:ffff:ffff:ffff:ffff:ffff
1033298:6600::/243298:66ff:ffff:ffff:ffff:ffff:ffff:ffff
1043298:6700::/243298:67ff:ffff:ffff:ffff:ffff:ffff:ffff
1053298:6800::/243298:68ff:ffff:ffff:ffff:ffff:ffff:ffff
1063298:6900::/243298:69ff:ffff:ffff:ffff:ffff:ffff:ffff
1073298:6a00::/243298:6aff:ffff:ffff:ffff:ffff:ffff:ffff
1083298:6b00::/243298:6bff:ffff:ffff:ffff:ffff:ffff:ffff
1093298:6c00::/243298:6cff:ffff:ffff:ffff:ffff:ffff:ffff
1103298:6d00::/243298:6dff:ffff:ffff:ffff:ffff:ffff:ffff
1113298:6e00::/243298:6eff:ffff:ffff:ffff:ffff:ffff:ffff
1123298:6f00::/243298:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1133298:7000::/243298:70ff:ffff:ffff:ffff:ffff:ffff:ffff
1143298:7100::/243298:71ff:ffff:ffff:ffff:ffff:ffff:ffff
1153298:7200::/243298:72ff:ffff:ffff:ffff:ffff:ffff:ffff
1163298:7300::/243298:73ff:ffff:ffff:ffff:ffff:ffff:ffff
1173298:7400::/243298:74ff:ffff:ffff:ffff:ffff:ffff:ffff
1183298:7500::/243298:75ff:ffff:ffff:ffff:ffff:ffff:ffff
1193298:7600::/243298:76ff:ffff:ffff:ffff:ffff:ffff:ffff
1203298:7700::/243298:77ff:ffff:ffff:ffff:ffff:ffff:ffff
1213298:7800::/243298:78ff:ffff:ffff:ffff:ffff:ffff:ffff
1223298:7900::/243298:79ff:ffff:ffff:ffff:ffff:ffff:ffff
1233298:7a00::/243298:7aff:ffff:ffff:ffff:ffff:ffff:ffff
1243298:7b00::/243298:7bff:ffff:ffff:ffff:ffff:ffff:ffff
1253298:7c00::/243298:7cff:ffff:ffff:ffff:ffff:ffff:ffff
1263298:7d00::/243298:7dff:ffff:ffff:ffff:ffff:ffff:ffff
1273298:7e00::/243298:7eff:ffff:ffff:ffff:ffff:ffff:ffff
1283298:7f00::/243298:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1293298:8000::/243298:80ff:ffff:ffff:ffff:ffff:ffff:ffff
1303298:8100::/243298:81ff:ffff:ffff:ffff:ffff:ffff:ffff
1313298:8200::/243298:82ff:ffff:ffff:ffff:ffff:ffff:ffff
1323298:8300::/243298:83ff:ffff:ffff:ffff:ffff:ffff:ffff
1333298:8400::/243298:84ff:ffff:ffff:ffff:ffff:ffff:ffff
1343298:8500::/243298:85ff:ffff:ffff:ffff:ffff:ffff:ffff
1353298:8600::/243298:86ff:ffff:ffff:ffff:ffff:ffff:ffff
1363298:8700::/243298:87ff:ffff:ffff:ffff:ffff:ffff:ffff
1373298:8800::/243298:88ff:ffff:ffff:ffff:ffff:ffff:ffff
1383298:8900::/243298:89ff:ffff:ffff:ffff:ffff:ffff:ffff
1393298:8a00::/243298:8aff:ffff:ffff:ffff:ffff:ffff:ffff
1403298:8b00::/243298:8bff:ffff:ffff:ffff:ffff:ffff:ffff
1413298:8c00::/243298:8cff:ffff:ffff:ffff:ffff:ffff:ffff
1423298:8d00::/243298:8dff:ffff:ffff:ffff:ffff:ffff:ffff
1433298:8e00::/243298:8eff:ffff:ffff:ffff:ffff:ffff:ffff
1443298:8f00::/243298:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1453298:9000::/243298:90ff:ffff:ffff:ffff:ffff:ffff:ffff
1463298:9100::/243298:91ff:ffff:ffff:ffff:ffff:ffff:ffff
1473298:9200::/243298:92ff:ffff:ffff:ffff:ffff:ffff:ffff
1483298:9300::/243298:93ff:ffff:ffff:ffff:ffff:ffff:ffff
1493298:9400::/243298:94ff:ffff:ffff:ffff:ffff:ffff:ffff
1503298:9500::/243298:95ff:ffff:ffff:ffff:ffff:ffff:ffff
1513298:9600::/243298:96ff:ffff:ffff:ffff:ffff:ffff:ffff
1523298:9700::/243298:97ff:ffff:ffff:ffff:ffff:ffff:ffff
1533298:9800::/243298:98ff:ffff:ffff:ffff:ffff:ffff:ffff
1543298:9900::/243298:99ff:ffff:ffff:ffff:ffff:ffff:ffff
1553298:9a00::/243298:9aff:ffff:ffff:ffff:ffff:ffff:ffff
1563298:9b00::/243298:9bff:ffff:ffff:ffff:ffff:ffff:ffff
1573298:9c00::/243298:9cff:ffff:ffff:ffff:ffff:ffff:ffff
1583298:9d00::/243298:9dff:ffff:ffff:ffff:ffff:ffff:ffff
1593298:9e00::/243298:9eff:ffff:ffff:ffff:ffff:ffff:ffff
1603298:9f00::/243298:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1613298:a000::/243298:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
1623298:a100::/243298:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
1633298:a200::/243298:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
1643298:a300::/243298:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
1653298:a400::/243298:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
1663298:a500::/243298:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
1673298:a600::/243298:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
1683298:a700::/243298:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
1693298:a800::/243298:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
1703298:a900::/243298:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
1713298:aa00::/243298:aaff:ffff:ffff:ffff:ffff:ffff:ffff
1723298:ab00::/243298:abff:ffff:ffff:ffff:ffff:ffff:ffff
1733298:ac00::/243298:acff:ffff:ffff:ffff:ffff:ffff:ffff
1743298:ad00::/243298:adff:ffff:ffff:ffff:ffff:ffff:ffff
1753298:ae00::/243298:aeff:ffff:ffff:ffff:ffff:ffff:ffff
1763298:af00::/243298:afff:ffff:ffff:ffff:ffff:ffff:ffff
1773298:b000::/243298:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
1783298:b100::/243298:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
1793298:b200::/243298:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
1803298:b300::/243298:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
1813298:b400::/243298:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
1823298:b500::/243298:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
1833298:b600::/243298:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
1843298:b700::/243298:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
1853298:b800::/243298:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
1863298:b900::/243298:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
1873298:ba00::/243298:baff:ffff:ffff:ffff:ffff:ffff:ffff
1883298:bb00::/243298:bbff:ffff:ffff:ffff:ffff:ffff:ffff
1893298:bc00::/243298:bcff:ffff:ffff:ffff:ffff:ffff:ffff
1903298:bd00::/243298:bdff:ffff:ffff:ffff:ffff:ffff:ffff
1913298:be00::/243298:beff:ffff:ffff:ffff:ffff:ffff:ffff
1923298:bf00::/243298:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1933298:c000::/243298:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
1943298:c100::/243298:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
1953298:c200::/243298:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
1963298:c300::/243298:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
1973298:c400::/243298:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
1983298:c500::/243298:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
1993298:c600::/243298:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
2003298:c700::/243298:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
2013298:c800::/243298:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
2023298:c900::/243298:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
2033298:ca00::/243298:caff:ffff:ffff:ffff:ffff:ffff:ffff
2043298:cb00::/243298:cbff:ffff:ffff:ffff:ffff:ffff:ffff
2053298:cc00::/243298:ccff:ffff:ffff:ffff:ffff:ffff:ffff
2063298:cd00::/243298:cdff:ffff:ffff:ffff:ffff:ffff:ffff
2073298:ce00::/243298:ceff:ffff:ffff:ffff:ffff:ffff:ffff
2083298:cf00::/243298:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2093298:d000::/243298:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
2103298:d100::/243298:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
2113298:d200::/243298:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
2123298:d300::/243298:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
2133298:d400::/243298:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
2143298:d500::/243298:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
2153298:d600::/243298:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
2163298:d700::/243298:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
2173298:d800::/243298:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
2183298:d900::/243298:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
2193298:da00::/243298:daff:ffff:ffff:ffff:ffff:ffff:ffff
2203298:db00::/243298:dbff:ffff:ffff:ffff:ffff:ffff:ffff
2213298:dc00::/243298:dcff:ffff:ffff:ffff:ffff:ffff:ffff
2223298:dd00::/243298:ddff:ffff:ffff:ffff:ffff:ffff:ffff
2233298:de00::/243298:deff:ffff:ffff:ffff:ffff:ffff:ffff
2243298:df00::/243298:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2253298:e000::/243298:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
2263298:e100::/243298:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
2273298:e200::/243298:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
2283298:e300::/243298:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
2293298:e400::/243298:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
2303298:e500::/243298:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
2313298:e600::/243298:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
2323298:e700::/243298:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
2333298:e800::/243298:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
2343298:e900::/243298:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
2353298:ea00::/243298:eaff:ffff:ffff:ffff:ffff:ffff:ffff
2363298:eb00::/243298:ebff:ffff:ffff:ffff:ffff:ffff:ffff
2373298:ec00::/243298:ecff:ffff:ffff:ffff:ffff:ffff:ffff
2383298:ed00::/243298:edff:ffff:ffff:ffff:ffff:ffff:ffff
2393298:ee00::/243298:eeff:ffff:ffff:ffff:ffff:ffff:ffff
2403298:ef00::/243298:efff:ffff:ffff:ffff:ffff:ffff:ffff
2413298:f000::/243298:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
2423298:f100::/243298:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
2433298:f200::/243298:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
2443298:f300::/243298:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
2453298:f400::/243298:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
2463298:f500::/243298:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
2473298:f600::/243298:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
2483298:f700::/243298:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
2493298:f800::/243298:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
2503298:f900::/243298:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
2513298:fa00::/243298:faff:ffff:ffff:ffff:ffff:ffff:ffff
2523298:fb00::/243298:fbff:ffff:ffff:ffff:ffff:ffff:ffff
2533298:fc00::/243298:fcff:ffff:ffff:ffff:ffff:ffff:ffff
2543298:fd00::/243298:fdff:ffff:ffff:ffff:ffff:ffff:ffff
2553298:fe00::/243298:feff:ffff:ffff:ffff:ffff:ffff:ffff
2563298:ff00::/243298: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.