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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/18
Addresses2^110
/64 networks2^46
Network
2ea5::/18
First address
2ea5::
Last address
2ea5:3fff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
1,298,074,214,633,706,907,132,624,082,305,024 (2^110)
/64 networks (LANs)
70,368,744,177,664 (2^46)
Full form
2ea5:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
0.5.a.e.2.ip6.arpa
1.5.a.e.2.ip6.arpa
2.5.a.e.2.ip6.arpa
3.5.a.e.2.ip6.arpa
/18 is not on a 4-bit boundary, so it takes 4 /20 zones.
Split into smaller subnets/32
/19 (2)/20 (4)/21 (8)/22 (16)/24 (64)/28 (1,024)/32 (16,384)

2ea5::/18 makes 16,384 subnets of /32; the first 256 are listed.

Subnets
#SubnetLast address
12ea5::/322ea5:0:ffff:ffff:ffff:ffff:ffff:ffff
22ea5:1::/322ea5:1:ffff:ffff:ffff:ffff:ffff:ffff
32ea5:2::/322ea5:2:ffff:ffff:ffff:ffff:ffff:ffff
42ea5:3::/322ea5:3:ffff:ffff:ffff:ffff:ffff:ffff
52ea5:4::/322ea5:4:ffff:ffff:ffff:ffff:ffff:ffff
62ea5:5::/322ea5:5:ffff:ffff:ffff:ffff:ffff:ffff
72ea5:6::/322ea5:6:ffff:ffff:ffff:ffff:ffff:ffff
82ea5:7::/322ea5:7:ffff:ffff:ffff:ffff:ffff:ffff
92ea5:8::/322ea5:8:ffff:ffff:ffff:ffff:ffff:ffff
102ea5:9::/322ea5:9:ffff:ffff:ffff:ffff:ffff:ffff
112ea5:a::/322ea5:a:ffff:ffff:ffff:ffff:ffff:ffff
122ea5:b::/322ea5:b:ffff:ffff:ffff:ffff:ffff:ffff
132ea5:c::/322ea5:c:ffff:ffff:ffff:ffff:ffff:ffff
142ea5:d::/322ea5:d:ffff:ffff:ffff:ffff:ffff:ffff
152ea5:e::/322ea5:e:ffff:ffff:ffff:ffff:ffff:ffff
162ea5:f::/322ea5:f:ffff:ffff:ffff:ffff:ffff:ffff
172ea5:10::/322ea5:10:ffff:ffff:ffff:ffff:ffff:ffff
182ea5:11::/322ea5:11:ffff:ffff:ffff:ffff:ffff:ffff
192ea5:12::/322ea5:12:ffff:ffff:ffff:ffff:ffff:ffff
202ea5:13::/322ea5:13:ffff:ffff:ffff:ffff:ffff:ffff
212ea5:14::/322ea5:14:ffff:ffff:ffff:ffff:ffff:ffff
222ea5:15::/322ea5:15:ffff:ffff:ffff:ffff:ffff:ffff
232ea5:16::/322ea5:16:ffff:ffff:ffff:ffff:ffff:ffff
242ea5:17::/322ea5:17:ffff:ffff:ffff:ffff:ffff:ffff
252ea5:18::/322ea5:18:ffff:ffff:ffff:ffff:ffff:ffff
262ea5:19::/322ea5:19:ffff:ffff:ffff:ffff:ffff:ffff
272ea5:1a::/322ea5:1a:ffff:ffff:ffff:ffff:ffff:ffff
282ea5:1b::/322ea5:1b:ffff:ffff:ffff:ffff:ffff:ffff
292ea5:1c::/322ea5:1c:ffff:ffff:ffff:ffff:ffff:ffff
302ea5:1d::/322ea5:1d:ffff:ffff:ffff:ffff:ffff:ffff
312ea5:1e::/322ea5:1e:ffff:ffff:ffff:ffff:ffff:ffff
322ea5:1f::/322ea5:1f:ffff:ffff:ffff:ffff:ffff:ffff
332ea5:20::/322ea5:20:ffff:ffff:ffff:ffff:ffff:ffff
342ea5:21::/322ea5:21:ffff:ffff:ffff:ffff:ffff:ffff
352ea5:22::/322ea5:22:ffff:ffff:ffff:ffff:ffff:ffff
362ea5:23::/322ea5:23:ffff:ffff:ffff:ffff:ffff:ffff
372ea5:24::/322ea5:24:ffff:ffff:ffff:ffff:ffff:ffff
382ea5:25::/322ea5:25:ffff:ffff:ffff:ffff:ffff:ffff
392ea5:26::/322ea5:26:ffff:ffff:ffff:ffff:ffff:ffff
402ea5:27::/322ea5:27:ffff:ffff:ffff:ffff:ffff:ffff
412ea5:28::/322ea5:28:ffff:ffff:ffff:ffff:ffff:ffff
422ea5:29::/322ea5:29:ffff:ffff:ffff:ffff:ffff:ffff
432ea5:2a::/322ea5:2a:ffff:ffff:ffff:ffff:ffff:ffff
442ea5:2b::/322ea5:2b:ffff:ffff:ffff:ffff:ffff:ffff
452ea5:2c::/322ea5:2c:ffff:ffff:ffff:ffff:ffff:ffff
462ea5:2d::/322ea5:2d:ffff:ffff:ffff:ffff:ffff:ffff
472ea5:2e::/322ea5:2e:ffff:ffff:ffff:ffff:ffff:ffff
482ea5:2f::/322ea5:2f:ffff:ffff:ffff:ffff:ffff:ffff
492ea5:30::/322ea5:30:ffff:ffff:ffff:ffff:ffff:ffff
502ea5:31::/322ea5:31:ffff:ffff:ffff:ffff:ffff:ffff
512ea5:32::/322ea5:32:ffff:ffff:ffff:ffff:ffff:ffff
522ea5:33::/322ea5:33:ffff:ffff:ffff:ffff:ffff:ffff
532ea5:34::/322ea5:34:ffff:ffff:ffff:ffff:ffff:ffff
542ea5:35::/322ea5:35:ffff:ffff:ffff:ffff:ffff:ffff
552ea5:36::/322ea5:36:ffff:ffff:ffff:ffff:ffff:ffff
562ea5:37::/322ea5:37:ffff:ffff:ffff:ffff:ffff:ffff
572ea5:38::/322ea5:38:ffff:ffff:ffff:ffff:ffff:ffff
582ea5:39::/322ea5:39:ffff:ffff:ffff:ffff:ffff:ffff
592ea5:3a::/322ea5:3a:ffff:ffff:ffff:ffff:ffff:ffff
602ea5:3b::/322ea5:3b:ffff:ffff:ffff:ffff:ffff:ffff
612ea5:3c::/322ea5:3c:ffff:ffff:ffff:ffff:ffff:ffff
622ea5:3d::/322ea5:3d:ffff:ffff:ffff:ffff:ffff:ffff
632ea5:3e::/322ea5:3e:ffff:ffff:ffff:ffff:ffff:ffff
642ea5:3f::/322ea5:3f:ffff:ffff:ffff:ffff:ffff:ffff
652ea5:40::/322ea5:40:ffff:ffff:ffff:ffff:ffff:ffff
662ea5:41::/322ea5:41:ffff:ffff:ffff:ffff:ffff:ffff
672ea5:42::/322ea5:42:ffff:ffff:ffff:ffff:ffff:ffff
682ea5:43::/322ea5:43:ffff:ffff:ffff:ffff:ffff:ffff
692ea5:44::/322ea5:44:ffff:ffff:ffff:ffff:ffff:ffff
702ea5:45::/322ea5:45:ffff:ffff:ffff:ffff:ffff:ffff
712ea5:46::/322ea5:46:ffff:ffff:ffff:ffff:ffff:ffff
722ea5:47::/322ea5:47:ffff:ffff:ffff:ffff:ffff:ffff
732ea5:48::/322ea5:48:ffff:ffff:ffff:ffff:ffff:ffff
742ea5:49::/322ea5:49:ffff:ffff:ffff:ffff:ffff:ffff
752ea5:4a::/322ea5:4a:ffff:ffff:ffff:ffff:ffff:ffff
762ea5:4b::/322ea5:4b:ffff:ffff:ffff:ffff:ffff:ffff
772ea5:4c::/322ea5:4c:ffff:ffff:ffff:ffff:ffff:ffff
782ea5:4d::/322ea5:4d:ffff:ffff:ffff:ffff:ffff:ffff
792ea5:4e::/322ea5:4e:ffff:ffff:ffff:ffff:ffff:ffff
802ea5:4f::/322ea5:4f:ffff:ffff:ffff:ffff:ffff:ffff
812ea5:50::/322ea5:50:ffff:ffff:ffff:ffff:ffff:ffff
822ea5:51::/322ea5:51:ffff:ffff:ffff:ffff:ffff:ffff
832ea5:52::/322ea5:52:ffff:ffff:ffff:ffff:ffff:ffff
842ea5:53::/322ea5:53:ffff:ffff:ffff:ffff:ffff:ffff
852ea5:54::/322ea5:54:ffff:ffff:ffff:ffff:ffff:ffff
862ea5:55::/322ea5:55:ffff:ffff:ffff:ffff:ffff:ffff
872ea5:56::/322ea5:56:ffff:ffff:ffff:ffff:ffff:ffff
882ea5:57::/322ea5:57:ffff:ffff:ffff:ffff:ffff:ffff
892ea5:58::/322ea5:58:ffff:ffff:ffff:ffff:ffff:ffff
902ea5:59::/322ea5:59:ffff:ffff:ffff:ffff:ffff:ffff
912ea5:5a::/322ea5:5a:ffff:ffff:ffff:ffff:ffff:ffff
922ea5:5b::/322ea5:5b:ffff:ffff:ffff:ffff:ffff:ffff
932ea5:5c::/322ea5:5c:ffff:ffff:ffff:ffff:ffff:ffff
942ea5:5d::/322ea5:5d:ffff:ffff:ffff:ffff:ffff:ffff
952ea5:5e::/322ea5:5e:ffff:ffff:ffff:ffff:ffff:ffff
962ea5:5f::/322ea5:5f:ffff:ffff:ffff:ffff:ffff:ffff
972ea5:60::/322ea5:60:ffff:ffff:ffff:ffff:ffff:ffff
982ea5:61::/322ea5:61:ffff:ffff:ffff:ffff:ffff:ffff
992ea5:62::/322ea5:62:ffff:ffff:ffff:ffff:ffff:ffff
1002ea5:63::/322ea5:63:ffff:ffff:ffff:ffff:ffff:ffff
1012ea5:64::/322ea5:64:ffff:ffff:ffff:ffff:ffff:ffff
1022ea5:65::/322ea5:65:ffff:ffff:ffff:ffff:ffff:ffff
1032ea5:66::/322ea5:66:ffff:ffff:ffff:ffff:ffff:ffff
1042ea5:67::/322ea5:67:ffff:ffff:ffff:ffff:ffff:ffff
1052ea5:68::/322ea5:68:ffff:ffff:ffff:ffff:ffff:ffff
1062ea5:69::/322ea5:69:ffff:ffff:ffff:ffff:ffff:ffff
1072ea5:6a::/322ea5:6a:ffff:ffff:ffff:ffff:ffff:ffff
1082ea5:6b::/322ea5:6b:ffff:ffff:ffff:ffff:ffff:ffff
1092ea5:6c::/322ea5:6c:ffff:ffff:ffff:ffff:ffff:ffff
1102ea5:6d::/322ea5:6d:ffff:ffff:ffff:ffff:ffff:ffff
1112ea5:6e::/322ea5:6e:ffff:ffff:ffff:ffff:ffff:ffff
1122ea5:6f::/322ea5:6f:ffff:ffff:ffff:ffff:ffff:ffff
1132ea5:70::/322ea5:70:ffff:ffff:ffff:ffff:ffff:ffff
1142ea5:71::/322ea5:71:ffff:ffff:ffff:ffff:ffff:ffff
1152ea5:72::/322ea5:72:ffff:ffff:ffff:ffff:ffff:ffff
1162ea5:73::/322ea5:73:ffff:ffff:ffff:ffff:ffff:ffff
1172ea5:74::/322ea5:74:ffff:ffff:ffff:ffff:ffff:ffff
1182ea5:75::/322ea5:75:ffff:ffff:ffff:ffff:ffff:ffff
1192ea5:76::/322ea5:76:ffff:ffff:ffff:ffff:ffff:ffff
1202ea5:77::/322ea5:77:ffff:ffff:ffff:ffff:ffff:ffff
1212ea5:78::/322ea5:78:ffff:ffff:ffff:ffff:ffff:ffff
1222ea5:79::/322ea5:79:ffff:ffff:ffff:ffff:ffff:ffff
1232ea5:7a::/322ea5:7a:ffff:ffff:ffff:ffff:ffff:ffff
1242ea5:7b::/322ea5:7b:ffff:ffff:ffff:ffff:ffff:ffff
1252ea5:7c::/322ea5:7c:ffff:ffff:ffff:ffff:ffff:ffff
1262ea5:7d::/322ea5:7d:ffff:ffff:ffff:ffff:ffff:ffff
1272ea5:7e::/322ea5:7e:ffff:ffff:ffff:ffff:ffff:ffff
1282ea5:7f::/322ea5:7f:ffff:ffff:ffff:ffff:ffff:ffff
1292ea5:80::/322ea5:80:ffff:ffff:ffff:ffff:ffff:ffff
1302ea5:81::/322ea5:81:ffff:ffff:ffff:ffff:ffff:ffff
1312ea5:82::/322ea5:82:ffff:ffff:ffff:ffff:ffff:ffff
1322ea5:83::/322ea5:83:ffff:ffff:ffff:ffff:ffff:ffff
1332ea5:84::/322ea5:84:ffff:ffff:ffff:ffff:ffff:ffff
1342ea5:85::/322ea5:85:ffff:ffff:ffff:ffff:ffff:ffff
1352ea5:86::/322ea5:86:ffff:ffff:ffff:ffff:ffff:ffff
1362ea5:87::/322ea5:87:ffff:ffff:ffff:ffff:ffff:ffff
1372ea5:88::/322ea5:88:ffff:ffff:ffff:ffff:ffff:ffff
1382ea5:89::/322ea5:89:ffff:ffff:ffff:ffff:ffff:ffff
1392ea5:8a::/322ea5:8a:ffff:ffff:ffff:ffff:ffff:ffff
1402ea5:8b::/322ea5:8b:ffff:ffff:ffff:ffff:ffff:ffff
1412ea5:8c::/322ea5:8c:ffff:ffff:ffff:ffff:ffff:ffff
1422ea5:8d::/322ea5:8d:ffff:ffff:ffff:ffff:ffff:ffff
1432ea5:8e::/322ea5:8e:ffff:ffff:ffff:ffff:ffff:ffff
1442ea5:8f::/322ea5:8f:ffff:ffff:ffff:ffff:ffff:ffff
1452ea5:90::/322ea5:90:ffff:ffff:ffff:ffff:ffff:ffff
1462ea5:91::/322ea5:91:ffff:ffff:ffff:ffff:ffff:ffff
1472ea5:92::/322ea5:92:ffff:ffff:ffff:ffff:ffff:ffff
1482ea5:93::/322ea5:93:ffff:ffff:ffff:ffff:ffff:ffff
1492ea5:94::/322ea5:94:ffff:ffff:ffff:ffff:ffff:ffff
1502ea5:95::/322ea5:95:ffff:ffff:ffff:ffff:ffff:ffff
1512ea5:96::/322ea5:96:ffff:ffff:ffff:ffff:ffff:ffff
1522ea5:97::/322ea5:97:ffff:ffff:ffff:ffff:ffff:ffff
1532ea5:98::/322ea5:98:ffff:ffff:ffff:ffff:ffff:ffff
1542ea5:99::/322ea5:99:ffff:ffff:ffff:ffff:ffff:ffff
1552ea5:9a::/322ea5:9a:ffff:ffff:ffff:ffff:ffff:ffff
1562ea5:9b::/322ea5:9b:ffff:ffff:ffff:ffff:ffff:ffff
1572ea5:9c::/322ea5:9c:ffff:ffff:ffff:ffff:ffff:ffff
1582ea5:9d::/322ea5:9d:ffff:ffff:ffff:ffff:ffff:ffff
1592ea5:9e::/322ea5:9e:ffff:ffff:ffff:ffff:ffff:ffff
1602ea5:9f::/322ea5:9f:ffff:ffff:ffff:ffff:ffff:ffff
1612ea5:a0::/322ea5:a0:ffff:ffff:ffff:ffff:ffff:ffff
1622ea5:a1::/322ea5:a1:ffff:ffff:ffff:ffff:ffff:ffff
1632ea5:a2::/322ea5:a2:ffff:ffff:ffff:ffff:ffff:ffff
1642ea5:a3::/322ea5:a3:ffff:ffff:ffff:ffff:ffff:ffff
1652ea5:a4::/322ea5:a4:ffff:ffff:ffff:ffff:ffff:ffff
1662ea5:a5::/322ea5:a5:ffff:ffff:ffff:ffff:ffff:ffff
1672ea5:a6::/322ea5:a6:ffff:ffff:ffff:ffff:ffff:ffff
1682ea5:a7::/322ea5:a7:ffff:ffff:ffff:ffff:ffff:ffff
1692ea5:a8::/322ea5:a8:ffff:ffff:ffff:ffff:ffff:ffff
1702ea5:a9::/322ea5:a9:ffff:ffff:ffff:ffff:ffff:ffff
1712ea5:aa::/322ea5:aa:ffff:ffff:ffff:ffff:ffff:ffff
1722ea5:ab::/322ea5:ab:ffff:ffff:ffff:ffff:ffff:ffff
1732ea5:ac::/322ea5:ac:ffff:ffff:ffff:ffff:ffff:ffff
1742ea5:ad::/322ea5:ad:ffff:ffff:ffff:ffff:ffff:ffff
1752ea5:ae::/322ea5:ae:ffff:ffff:ffff:ffff:ffff:ffff
1762ea5:af::/322ea5:af:ffff:ffff:ffff:ffff:ffff:ffff
1772ea5:b0::/322ea5:b0:ffff:ffff:ffff:ffff:ffff:ffff
1782ea5:b1::/322ea5:b1:ffff:ffff:ffff:ffff:ffff:ffff
1792ea5:b2::/322ea5:b2:ffff:ffff:ffff:ffff:ffff:ffff
1802ea5:b3::/322ea5:b3:ffff:ffff:ffff:ffff:ffff:ffff
1812ea5:b4::/322ea5:b4:ffff:ffff:ffff:ffff:ffff:ffff
1822ea5:b5::/322ea5:b5:ffff:ffff:ffff:ffff:ffff:ffff
1832ea5:b6::/322ea5:b6:ffff:ffff:ffff:ffff:ffff:ffff
1842ea5:b7::/322ea5:b7:ffff:ffff:ffff:ffff:ffff:ffff
1852ea5:b8::/322ea5:b8:ffff:ffff:ffff:ffff:ffff:ffff
1862ea5:b9::/322ea5:b9:ffff:ffff:ffff:ffff:ffff:ffff
1872ea5:ba::/322ea5:ba:ffff:ffff:ffff:ffff:ffff:ffff
1882ea5:bb::/322ea5:bb:ffff:ffff:ffff:ffff:ffff:ffff
1892ea5:bc::/322ea5:bc:ffff:ffff:ffff:ffff:ffff:ffff
1902ea5:bd::/322ea5:bd:ffff:ffff:ffff:ffff:ffff:ffff
1912ea5:be::/322ea5:be:ffff:ffff:ffff:ffff:ffff:ffff
1922ea5:bf::/322ea5:bf:ffff:ffff:ffff:ffff:ffff:ffff
1932ea5:c0::/322ea5:c0:ffff:ffff:ffff:ffff:ffff:ffff
1942ea5:c1::/322ea5:c1:ffff:ffff:ffff:ffff:ffff:ffff
1952ea5:c2::/322ea5:c2:ffff:ffff:ffff:ffff:ffff:ffff
1962ea5:c3::/322ea5:c3:ffff:ffff:ffff:ffff:ffff:ffff
1972ea5:c4::/322ea5:c4:ffff:ffff:ffff:ffff:ffff:ffff
1982ea5:c5::/322ea5:c5:ffff:ffff:ffff:ffff:ffff:ffff
1992ea5:c6::/322ea5:c6:ffff:ffff:ffff:ffff:ffff:ffff
2002ea5:c7::/322ea5:c7:ffff:ffff:ffff:ffff:ffff:ffff
2012ea5:c8::/322ea5:c8:ffff:ffff:ffff:ffff:ffff:ffff
2022ea5:c9::/322ea5:c9:ffff:ffff:ffff:ffff:ffff:ffff
2032ea5:ca::/322ea5:ca:ffff:ffff:ffff:ffff:ffff:ffff
2042ea5:cb::/322ea5:cb:ffff:ffff:ffff:ffff:ffff:ffff
2052ea5:cc::/322ea5:cc:ffff:ffff:ffff:ffff:ffff:ffff
2062ea5:cd::/322ea5:cd:ffff:ffff:ffff:ffff:ffff:ffff
2072ea5:ce::/322ea5:ce:ffff:ffff:ffff:ffff:ffff:ffff
2082ea5:cf::/322ea5:cf:ffff:ffff:ffff:ffff:ffff:ffff
2092ea5:d0::/322ea5:d0:ffff:ffff:ffff:ffff:ffff:ffff
2102ea5:d1::/322ea5:d1:ffff:ffff:ffff:ffff:ffff:ffff
2112ea5:d2::/322ea5:d2:ffff:ffff:ffff:ffff:ffff:ffff
2122ea5:d3::/322ea5:d3:ffff:ffff:ffff:ffff:ffff:ffff
2132ea5:d4::/322ea5:d4:ffff:ffff:ffff:ffff:ffff:ffff
2142ea5:d5::/322ea5:d5:ffff:ffff:ffff:ffff:ffff:ffff
2152ea5:d6::/322ea5:d6:ffff:ffff:ffff:ffff:ffff:ffff
2162ea5:d7::/322ea5:d7:ffff:ffff:ffff:ffff:ffff:ffff
2172ea5:d8::/322ea5:d8:ffff:ffff:ffff:ffff:ffff:ffff
2182ea5:d9::/322ea5:d9:ffff:ffff:ffff:ffff:ffff:ffff
2192ea5:da::/322ea5:da:ffff:ffff:ffff:ffff:ffff:ffff
2202ea5:db::/322ea5:db:ffff:ffff:ffff:ffff:ffff:ffff
2212ea5:dc::/322ea5:dc:ffff:ffff:ffff:ffff:ffff:ffff
2222ea5:dd::/322ea5:dd:ffff:ffff:ffff:ffff:ffff:ffff
2232ea5:de::/322ea5:de:ffff:ffff:ffff:ffff:ffff:ffff
2242ea5:df::/322ea5:df:ffff:ffff:ffff:ffff:ffff:ffff
2252ea5:e0::/322ea5:e0:ffff:ffff:ffff:ffff:ffff:ffff
2262ea5:e1::/322ea5:e1:ffff:ffff:ffff:ffff:ffff:ffff
2272ea5:e2::/322ea5:e2:ffff:ffff:ffff:ffff:ffff:ffff
2282ea5:e3::/322ea5:e3:ffff:ffff:ffff:ffff:ffff:ffff
2292ea5:e4::/322ea5:e4:ffff:ffff:ffff:ffff:ffff:ffff
2302ea5:e5::/322ea5:e5:ffff:ffff:ffff:ffff:ffff:ffff
2312ea5:e6::/322ea5:e6:ffff:ffff:ffff:ffff:ffff:ffff
2322ea5:e7::/322ea5:e7:ffff:ffff:ffff:ffff:ffff:ffff
2332ea5:e8::/322ea5:e8:ffff:ffff:ffff:ffff:ffff:ffff
2342ea5:e9::/322ea5:e9:ffff:ffff:ffff:ffff:ffff:ffff
2352ea5:ea::/322ea5:ea:ffff:ffff:ffff:ffff:ffff:ffff
2362ea5:eb::/322ea5:eb:ffff:ffff:ffff:ffff:ffff:ffff
2372ea5:ec::/322ea5:ec:ffff:ffff:ffff:ffff:ffff:ffff
2382ea5:ed::/322ea5:ed:ffff:ffff:ffff:ffff:ffff:ffff
2392ea5:ee::/322ea5:ee:ffff:ffff:ffff:ffff:ffff:ffff
2402ea5:ef::/322ea5:ef:ffff:ffff:ffff:ffff:ffff:ffff
2412ea5:f0::/322ea5:f0:ffff:ffff:ffff:ffff:ffff:ffff
2422ea5:f1::/322ea5:f1:ffff:ffff:ffff:ffff:ffff:ffff
2432ea5:f2::/322ea5:f2:ffff:ffff:ffff:ffff:ffff:ffff
2442ea5:f3::/322ea5:f3:ffff:ffff:ffff:ffff:ffff:ffff
2452ea5:f4::/322ea5:f4:ffff:ffff:ffff:ffff:ffff:ffff
2462ea5:f5::/322ea5:f5:ffff:ffff:ffff:ffff:ffff:ffff
2472ea5:f6::/322ea5:f6:ffff:ffff:ffff:ffff:ffff:ffff
2482ea5:f7::/322ea5:f7:ffff:ffff:ffff:ffff:ffff:ffff
2492ea5:f8::/322ea5:f8:ffff:ffff:ffff:ffff:ffff:ffff
2502ea5:f9::/322ea5:f9:ffff:ffff:ffff:ffff:ffff:ffff
2512ea5:fa::/322ea5:fa:ffff:ffff:ffff:ffff:ffff:ffff
2522ea5:fb::/322ea5:fb:ffff:ffff:ffff:ffff:ffff:ffff
2532ea5:fc::/322ea5:fc:ffff:ffff:ffff:ffff:ffff:ffff
2542ea5:fd::/322ea5:fd:ffff:ffff:ffff:ffff:ffff:ffff
2552ea5:fe::/322ea5:fe:ffff:ffff:ffff:ffff:ffff:ffff
2562ea5:ff::/322ea5: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.