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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
2098::/16
First address
2098::
Last address
2098: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
2098:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
8.9.0.2.ip6.arpa
Split into smaller subnets/32
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

2098::/16 makes 65,536 subnets of /32; the first 256 are listed.

Subnets
#SubnetLast address
12098::/322098:0:ffff:ffff:ffff:ffff:ffff:ffff
22098:1::/322098:1:ffff:ffff:ffff:ffff:ffff:ffff
32098:2::/322098:2:ffff:ffff:ffff:ffff:ffff:ffff
42098:3::/322098:3:ffff:ffff:ffff:ffff:ffff:ffff
52098:4::/322098:4:ffff:ffff:ffff:ffff:ffff:ffff
62098:5::/322098:5:ffff:ffff:ffff:ffff:ffff:ffff
72098:6::/322098:6:ffff:ffff:ffff:ffff:ffff:ffff
82098:7::/322098:7:ffff:ffff:ffff:ffff:ffff:ffff
92098:8::/322098:8:ffff:ffff:ffff:ffff:ffff:ffff
102098:9::/322098:9:ffff:ffff:ffff:ffff:ffff:ffff
112098:a::/322098:a:ffff:ffff:ffff:ffff:ffff:ffff
122098:b::/322098:b:ffff:ffff:ffff:ffff:ffff:ffff
132098:c::/322098:c:ffff:ffff:ffff:ffff:ffff:ffff
142098:d::/322098:d:ffff:ffff:ffff:ffff:ffff:ffff
152098:e::/322098:e:ffff:ffff:ffff:ffff:ffff:ffff
162098:f::/322098:f:ffff:ffff:ffff:ffff:ffff:ffff
172098:10::/322098:10:ffff:ffff:ffff:ffff:ffff:ffff
182098:11::/322098:11:ffff:ffff:ffff:ffff:ffff:ffff
192098:12::/322098:12:ffff:ffff:ffff:ffff:ffff:ffff
202098:13::/322098:13:ffff:ffff:ffff:ffff:ffff:ffff
212098:14::/322098:14:ffff:ffff:ffff:ffff:ffff:ffff
222098:15::/322098:15:ffff:ffff:ffff:ffff:ffff:ffff
232098:16::/322098:16:ffff:ffff:ffff:ffff:ffff:ffff
242098:17::/322098:17:ffff:ffff:ffff:ffff:ffff:ffff
252098:18::/322098:18:ffff:ffff:ffff:ffff:ffff:ffff
262098:19::/322098:19:ffff:ffff:ffff:ffff:ffff:ffff
272098:1a::/322098:1a:ffff:ffff:ffff:ffff:ffff:ffff
282098:1b::/322098:1b:ffff:ffff:ffff:ffff:ffff:ffff
292098:1c::/322098:1c:ffff:ffff:ffff:ffff:ffff:ffff
302098:1d::/322098:1d:ffff:ffff:ffff:ffff:ffff:ffff
312098:1e::/322098:1e:ffff:ffff:ffff:ffff:ffff:ffff
322098:1f::/322098:1f:ffff:ffff:ffff:ffff:ffff:ffff
332098:20::/322098:20:ffff:ffff:ffff:ffff:ffff:ffff
342098:21::/322098:21:ffff:ffff:ffff:ffff:ffff:ffff
352098:22::/322098:22:ffff:ffff:ffff:ffff:ffff:ffff
362098:23::/322098:23:ffff:ffff:ffff:ffff:ffff:ffff
372098:24::/322098:24:ffff:ffff:ffff:ffff:ffff:ffff
382098:25::/322098:25:ffff:ffff:ffff:ffff:ffff:ffff
392098:26::/322098:26:ffff:ffff:ffff:ffff:ffff:ffff
402098:27::/322098:27:ffff:ffff:ffff:ffff:ffff:ffff
412098:28::/322098:28:ffff:ffff:ffff:ffff:ffff:ffff
422098:29::/322098:29:ffff:ffff:ffff:ffff:ffff:ffff
432098:2a::/322098:2a:ffff:ffff:ffff:ffff:ffff:ffff
442098:2b::/322098:2b:ffff:ffff:ffff:ffff:ffff:ffff
452098:2c::/322098:2c:ffff:ffff:ffff:ffff:ffff:ffff
462098:2d::/322098:2d:ffff:ffff:ffff:ffff:ffff:ffff
472098:2e::/322098:2e:ffff:ffff:ffff:ffff:ffff:ffff
482098:2f::/322098:2f:ffff:ffff:ffff:ffff:ffff:ffff
492098:30::/322098:30:ffff:ffff:ffff:ffff:ffff:ffff
502098:31::/322098:31:ffff:ffff:ffff:ffff:ffff:ffff
512098:32::/322098:32:ffff:ffff:ffff:ffff:ffff:ffff
522098:33::/322098:33:ffff:ffff:ffff:ffff:ffff:ffff
532098:34::/322098:34:ffff:ffff:ffff:ffff:ffff:ffff
542098:35::/322098:35:ffff:ffff:ffff:ffff:ffff:ffff
552098:36::/322098:36:ffff:ffff:ffff:ffff:ffff:ffff
562098:37::/322098:37:ffff:ffff:ffff:ffff:ffff:ffff
572098:38::/322098:38:ffff:ffff:ffff:ffff:ffff:ffff
582098:39::/322098:39:ffff:ffff:ffff:ffff:ffff:ffff
592098:3a::/322098:3a:ffff:ffff:ffff:ffff:ffff:ffff
602098:3b::/322098:3b:ffff:ffff:ffff:ffff:ffff:ffff
612098:3c::/322098:3c:ffff:ffff:ffff:ffff:ffff:ffff
622098:3d::/322098:3d:ffff:ffff:ffff:ffff:ffff:ffff
632098:3e::/322098:3e:ffff:ffff:ffff:ffff:ffff:ffff
642098:3f::/322098:3f:ffff:ffff:ffff:ffff:ffff:ffff
652098:40::/322098:40:ffff:ffff:ffff:ffff:ffff:ffff
662098:41::/322098:41:ffff:ffff:ffff:ffff:ffff:ffff
672098:42::/322098:42:ffff:ffff:ffff:ffff:ffff:ffff
682098:43::/322098:43:ffff:ffff:ffff:ffff:ffff:ffff
692098:44::/322098:44:ffff:ffff:ffff:ffff:ffff:ffff
702098:45::/322098:45:ffff:ffff:ffff:ffff:ffff:ffff
712098:46::/322098:46:ffff:ffff:ffff:ffff:ffff:ffff
722098:47::/322098:47:ffff:ffff:ffff:ffff:ffff:ffff
732098:48::/322098:48:ffff:ffff:ffff:ffff:ffff:ffff
742098:49::/322098:49:ffff:ffff:ffff:ffff:ffff:ffff
752098:4a::/322098:4a:ffff:ffff:ffff:ffff:ffff:ffff
762098:4b::/322098:4b:ffff:ffff:ffff:ffff:ffff:ffff
772098:4c::/322098:4c:ffff:ffff:ffff:ffff:ffff:ffff
782098:4d::/322098:4d:ffff:ffff:ffff:ffff:ffff:ffff
792098:4e::/322098:4e:ffff:ffff:ffff:ffff:ffff:ffff
802098:4f::/322098:4f:ffff:ffff:ffff:ffff:ffff:ffff
812098:50::/322098:50:ffff:ffff:ffff:ffff:ffff:ffff
822098:51::/322098:51:ffff:ffff:ffff:ffff:ffff:ffff
832098:52::/322098:52:ffff:ffff:ffff:ffff:ffff:ffff
842098:53::/322098:53:ffff:ffff:ffff:ffff:ffff:ffff
852098:54::/322098:54:ffff:ffff:ffff:ffff:ffff:ffff
862098:55::/322098:55:ffff:ffff:ffff:ffff:ffff:ffff
872098:56::/322098:56:ffff:ffff:ffff:ffff:ffff:ffff
882098:57::/322098:57:ffff:ffff:ffff:ffff:ffff:ffff
892098:58::/322098:58:ffff:ffff:ffff:ffff:ffff:ffff
902098:59::/322098:59:ffff:ffff:ffff:ffff:ffff:ffff
912098:5a::/322098:5a:ffff:ffff:ffff:ffff:ffff:ffff
922098:5b::/322098:5b:ffff:ffff:ffff:ffff:ffff:ffff
932098:5c::/322098:5c:ffff:ffff:ffff:ffff:ffff:ffff
942098:5d::/322098:5d:ffff:ffff:ffff:ffff:ffff:ffff
952098:5e::/322098:5e:ffff:ffff:ffff:ffff:ffff:ffff
962098:5f::/322098:5f:ffff:ffff:ffff:ffff:ffff:ffff
972098:60::/322098:60:ffff:ffff:ffff:ffff:ffff:ffff
982098:61::/322098:61:ffff:ffff:ffff:ffff:ffff:ffff
992098:62::/322098:62:ffff:ffff:ffff:ffff:ffff:ffff
1002098:63::/322098:63:ffff:ffff:ffff:ffff:ffff:ffff
1012098:64::/322098:64:ffff:ffff:ffff:ffff:ffff:ffff
1022098:65::/322098:65:ffff:ffff:ffff:ffff:ffff:ffff
1032098:66::/322098:66:ffff:ffff:ffff:ffff:ffff:ffff
1042098:67::/322098:67:ffff:ffff:ffff:ffff:ffff:ffff
1052098:68::/322098:68:ffff:ffff:ffff:ffff:ffff:ffff
1062098:69::/322098:69:ffff:ffff:ffff:ffff:ffff:ffff
1072098:6a::/322098:6a:ffff:ffff:ffff:ffff:ffff:ffff
1082098:6b::/322098:6b:ffff:ffff:ffff:ffff:ffff:ffff
1092098:6c::/322098:6c:ffff:ffff:ffff:ffff:ffff:ffff
1102098:6d::/322098:6d:ffff:ffff:ffff:ffff:ffff:ffff
1112098:6e::/322098:6e:ffff:ffff:ffff:ffff:ffff:ffff
1122098:6f::/322098:6f:ffff:ffff:ffff:ffff:ffff:ffff
1132098:70::/322098:70:ffff:ffff:ffff:ffff:ffff:ffff
1142098:71::/322098:71:ffff:ffff:ffff:ffff:ffff:ffff
1152098:72::/322098:72:ffff:ffff:ffff:ffff:ffff:ffff
1162098:73::/322098:73:ffff:ffff:ffff:ffff:ffff:ffff
1172098:74::/322098:74:ffff:ffff:ffff:ffff:ffff:ffff
1182098:75::/322098:75:ffff:ffff:ffff:ffff:ffff:ffff
1192098:76::/322098:76:ffff:ffff:ffff:ffff:ffff:ffff
1202098:77::/322098:77:ffff:ffff:ffff:ffff:ffff:ffff
1212098:78::/322098:78:ffff:ffff:ffff:ffff:ffff:ffff
1222098:79::/322098:79:ffff:ffff:ffff:ffff:ffff:ffff
1232098:7a::/322098:7a:ffff:ffff:ffff:ffff:ffff:ffff
1242098:7b::/322098:7b:ffff:ffff:ffff:ffff:ffff:ffff
1252098:7c::/322098:7c:ffff:ffff:ffff:ffff:ffff:ffff
1262098:7d::/322098:7d:ffff:ffff:ffff:ffff:ffff:ffff
1272098:7e::/322098:7e:ffff:ffff:ffff:ffff:ffff:ffff
1282098:7f::/322098:7f:ffff:ffff:ffff:ffff:ffff:ffff
1292098:80::/322098:80:ffff:ffff:ffff:ffff:ffff:ffff
1302098:81::/322098:81:ffff:ffff:ffff:ffff:ffff:ffff
1312098:82::/322098:82:ffff:ffff:ffff:ffff:ffff:ffff
1322098:83::/322098:83:ffff:ffff:ffff:ffff:ffff:ffff
1332098:84::/322098:84:ffff:ffff:ffff:ffff:ffff:ffff
1342098:85::/322098:85:ffff:ffff:ffff:ffff:ffff:ffff
1352098:86::/322098:86:ffff:ffff:ffff:ffff:ffff:ffff
1362098:87::/322098:87:ffff:ffff:ffff:ffff:ffff:ffff
1372098:88::/322098:88:ffff:ffff:ffff:ffff:ffff:ffff
1382098:89::/322098:89:ffff:ffff:ffff:ffff:ffff:ffff
1392098:8a::/322098:8a:ffff:ffff:ffff:ffff:ffff:ffff
1402098:8b::/322098:8b:ffff:ffff:ffff:ffff:ffff:ffff
1412098:8c::/322098:8c:ffff:ffff:ffff:ffff:ffff:ffff
1422098:8d::/322098:8d:ffff:ffff:ffff:ffff:ffff:ffff
1432098:8e::/322098:8e:ffff:ffff:ffff:ffff:ffff:ffff
1442098:8f::/322098:8f:ffff:ffff:ffff:ffff:ffff:ffff
1452098:90::/322098:90:ffff:ffff:ffff:ffff:ffff:ffff
1462098:91::/322098:91:ffff:ffff:ffff:ffff:ffff:ffff
1472098:92::/322098:92:ffff:ffff:ffff:ffff:ffff:ffff
1482098:93::/322098:93:ffff:ffff:ffff:ffff:ffff:ffff
1492098:94::/322098:94:ffff:ffff:ffff:ffff:ffff:ffff
1502098:95::/322098:95:ffff:ffff:ffff:ffff:ffff:ffff
1512098:96::/322098:96:ffff:ffff:ffff:ffff:ffff:ffff
1522098:97::/322098:97:ffff:ffff:ffff:ffff:ffff:ffff
1532098:98::/322098:98:ffff:ffff:ffff:ffff:ffff:ffff
1542098:99::/322098:99:ffff:ffff:ffff:ffff:ffff:ffff
1552098:9a::/322098:9a:ffff:ffff:ffff:ffff:ffff:ffff
1562098:9b::/322098:9b:ffff:ffff:ffff:ffff:ffff:ffff
1572098:9c::/322098:9c:ffff:ffff:ffff:ffff:ffff:ffff
1582098:9d::/322098:9d:ffff:ffff:ffff:ffff:ffff:ffff
1592098:9e::/322098:9e:ffff:ffff:ffff:ffff:ffff:ffff
1602098:9f::/322098:9f:ffff:ffff:ffff:ffff:ffff:ffff
1612098:a0::/322098:a0:ffff:ffff:ffff:ffff:ffff:ffff
1622098:a1::/322098:a1:ffff:ffff:ffff:ffff:ffff:ffff
1632098:a2::/322098:a2:ffff:ffff:ffff:ffff:ffff:ffff
1642098:a3::/322098:a3:ffff:ffff:ffff:ffff:ffff:ffff
1652098:a4::/322098:a4:ffff:ffff:ffff:ffff:ffff:ffff
1662098:a5::/322098:a5:ffff:ffff:ffff:ffff:ffff:ffff
1672098:a6::/322098:a6:ffff:ffff:ffff:ffff:ffff:ffff
1682098:a7::/322098:a7:ffff:ffff:ffff:ffff:ffff:ffff
1692098:a8::/322098:a8:ffff:ffff:ffff:ffff:ffff:ffff
1702098:a9::/322098:a9:ffff:ffff:ffff:ffff:ffff:ffff
1712098:aa::/322098:aa:ffff:ffff:ffff:ffff:ffff:ffff
1722098:ab::/322098:ab:ffff:ffff:ffff:ffff:ffff:ffff
1732098:ac::/322098:ac:ffff:ffff:ffff:ffff:ffff:ffff
1742098:ad::/322098:ad:ffff:ffff:ffff:ffff:ffff:ffff
1752098:ae::/322098:ae:ffff:ffff:ffff:ffff:ffff:ffff
1762098:af::/322098:af:ffff:ffff:ffff:ffff:ffff:ffff
1772098:b0::/322098:b0:ffff:ffff:ffff:ffff:ffff:ffff
1782098:b1::/322098:b1:ffff:ffff:ffff:ffff:ffff:ffff
1792098:b2::/322098:b2:ffff:ffff:ffff:ffff:ffff:ffff
1802098:b3::/322098:b3:ffff:ffff:ffff:ffff:ffff:ffff
1812098:b4::/322098:b4:ffff:ffff:ffff:ffff:ffff:ffff
1822098:b5::/322098:b5:ffff:ffff:ffff:ffff:ffff:ffff
1832098:b6::/322098:b6:ffff:ffff:ffff:ffff:ffff:ffff
1842098:b7::/322098:b7:ffff:ffff:ffff:ffff:ffff:ffff
1852098:b8::/322098:b8:ffff:ffff:ffff:ffff:ffff:ffff
1862098:b9::/322098:b9:ffff:ffff:ffff:ffff:ffff:ffff
1872098:ba::/322098:ba:ffff:ffff:ffff:ffff:ffff:ffff
1882098:bb::/322098:bb:ffff:ffff:ffff:ffff:ffff:ffff
1892098:bc::/322098:bc:ffff:ffff:ffff:ffff:ffff:ffff
1902098:bd::/322098:bd:ffff:ffff:ffff:ffff:ffff:ffff
1912098:be::/322098:be:ffff:ffff:ffff:ffff:ffff:ffff
1922098:bf::/322098:bf:ffff:ffff:ffff:ffff:ffff:ffff
1932098:c0::/322098:c0:ffff:ffff:ffff:ffff:ffff:ffff
1942098:c1::/322098:c1:ffff:ffff:ffff:ffff:ffff:ffff
1952098:c2::/322098:c2:ffff:ffff:ffff:ffff:ffff:ffff
1962098:c3::/322098:c3:ffff:ffff:ffff:ffff:ffff:ffff
1972098:c4::/322098:c4:ffff:ffff:ffff:ffff:ffff:ffff
1982098:c5::/322098:c5:ffff:ffff:ffff:ffff:ffff:ffff
1992098:c6::/322098:c6:ffff:ffff:ffff:ffff:ffff:ffff
2002098:c7::/322098:c7:ffff:ffff:ffff:ffff:ffff:ffff
2012098:c8::/322098:c8:ffff:ffff:ffff:ffff:ffff:ffff
2022098:c9::/322098:c9:ffff:ffff:ffff:ffff:ffff:ffff
2032098:ca::/322098:ca:ffff:ffff:ffff:ffff:ffff:ffff
2042098:cb::/322098:cb:ffff:ffff:ffff:ffff:ffff:ffff
2052098:cc::/322098:cc:ffff:ffff:ffff:ffff:ffff:ffff
2062098:cd::/322098:cd:ffff:ffff:ffff:ffff:ffff:ffff
2072098:ce::/322098:ce:ffff:ffff:ffff:ffff:ffff:ffff
2082098:cf::/322098:cf:ffff:ffff:ffff:ffff:ffff:ffff
2092098:d0::/322098:d0:ffff:ffff:ffff:ffff:ffff:ffff
2102098:d1::/322098:d1:ffff:ffff:ffff:ffff:ffff:ffff
2112098:d2::/322098:d2:ffff:ffff:ffff:ffff:ffff:ffff
2122098:d3::/322098:d3:ffff:ffff:ffff:ffff:ffff:ffff
2132098:d4::/322098:d4:ffff:ffff:ffff:ffff:ffff:ffff
2142098:d5::/322098:d5:ffff:ffff:ffff:ffff:ffff:ffff
2152098:d6::/322098:d6:ffff:ffff:ffff:ffff:ffff:ffff
2162098:d7::/322098:d7:ffff:ffff:ffff:ffff:ffff:ffff
2172098:d8::/322098:d8:ffff:ffff:ffff:ffff:ffff:ffff
2182098:d9::/322098:d9:ffff:ffff:ffff:ffff:ffff:ffff
2192098:da::/322098:da:ffff:ffff:ffff:ffff:ffff:ffff
2202098:db::/322098:db:ffff:ffff:ffff:ffff:ffff:ffff
2212098:dc::/322098:dc:ffff:ffff:ffff:ffff:ffff:ffff
2222098:dd::/322098:dd:ffff:ffff:ffff:ffff:ffff:ffff
2232098:de::/322098:de:ffff:ffff:ffff:ffff:ffff:ffff
2242098:df::/322098:df:ffff:ffff:ffff:ffff:ffff:ffff
2252098:e0::/322098:e0:ffff:ffff:ffff:ffff:ffff:ffff
2262098:e1::/322098:e1:ffff:ffff:ffff:ffff:ffff:ffff
2272098:e2::/322098:e2:ffff:ffff:ffff:ffff:ffff:ffff
2282098:e3::/322098:e3:ffff:ffff:ffff:ffff:ffff:ffff
2292098:e4::/322098:e4:ffff:ffff:ffff:ffff:ffff:ffff
2302098:e5::/322098:e5:ffff:ffff:ffff:ffff:ffff:ffff
2312098:e6::/322098:e6:ffff:ffff:ffff:ffff:ffff:ffff
2322098:e7::/322098:e7:ffff:ffff:ffff:ffff:ffff:ffff
2332098:e8::/322098:e8:ffff:ffff:ffff:ffff:ffff:ffff
2342098:e9::/322098:e9:ffff:ffff:ffff:ffff:ffff:ffff
2352098:ea::/322098:ea:ffff:ffff:ffff:ffff:ffff:ffff
2362098:eb::/322098:eb:ffff:ffff:ffff:ffff:ffff:ffff
2372098:ec::/322098:ec:ffff:ffff:ffff:ffff:ffff:ffff
2382098:ed::/322098:ed:ffff:ffff:ffff:ffff:ffff:ffff
2392098:ee::/322098:ee:ffff:ffff:ffff:ffff:ffff:ffff
2402098:ef::/322098:ef:ffff:ffff:ffff:ffff:ffff:ffff
2412098:f0::/322098:f0:ffff:ffff:ffff:ffff:ffff:ffff
2422098:f1::/322098:f1:ffff:ffff:ffff:ffff:ffff:ffff
2432098:f2::/322098:f2:ffff:ffff:ffff:ffff:ffff:ffff
2442098:f3::/322098:f3:ffff:ffff:ffff:ffff:ffff:ffff
2452098:f4::/322098:f4:ffff:ffff:ffff:ffff:ffff:ffff
2462098:f5::/322098:f5:ffff:ffff:ffff:ffff:ffff:ffff
2472098:f6::/322098:f6:ffff:ffff:ffff:ffff:ffff:ffff
2482098:f7::/322098:f7:ffff:ffff:ffff:ffff:ffff:ffff
2492098:f8::/322098:f8:ffff:ffff:ffff:ffff:ffff:ffff
2502098:f9::/322098:f9:ffff:ffff:ffff:ffff:ffff:ffff
2512098:fa::/322098:fa:ffff:ffff:ffff:ffff:ffff:ffff
2522098:fb::/322098:fb:ffff:ffff:ffff:ffff:ffff:ffff
2532098:fc::/322098:fc:ffff:ffff:ffff:ffff:ffff:ffff
2542098:fd::/322098:fd:ffff:ffff:ffff:ffff:ffff:ffff
2552098:fe::/322098:fe:ffff:ffff:ffff:ffff:ffff:ffff
2562098:ff::/322098:ff: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.