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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
2ed4::/16
First address
2ed4::
Last address
2ed4: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
2ed4:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
4.d.e.2.ip6.arpa
Split into smaller subnets/32
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

2ed4::/16 makes 65,536 subnets of /32; the first 256 are listed.

Subnets
#SubnetLast address
12ed4::/322ed4:0:ffff:ffff:ffff:ffff:ffff:ffff
22ed4:1::/322ed4:1:ffff:ffff:ffff:ffff:ffff:ffff
32ed4:2::/322ed4:2:ffff:ffff:ffff:ffff:ffff:ffff
42ed4:3::/322ed4:3:ffff:ffff:ffff:ffff:ffff:ffff
52ed4:4::/322ed4:4:ffff:ffff:ffff:ffff:ffff:ffff
62ed4:5::/322ed4:5:ffff:ffff:ffff:ffff:ffff:ffff
72ed4:6::/322ed4:6:ffff:ffff:ffff:ffff:ffff:ffff
82ed4:7::/322ed4:7:ffff:ffff:ffff:ffff:ffff:ffff
92ed4:8::/322ed4:8:ffff:ffff:ffff:ffff:ffff:ffff
102ed4:9::/322ed4:9:ffff:ffff:ffff:ffff:ffff:ffff
112ed4:a::/322ed4:a:ffff:ffff:ffff:ffff:ffff:ffff
122ed4:b::/322ed4:b:ffff:ffff:ffff:ffff:ffff:ffff
132ed4:c::/322ed4:c:ffff:ffff:ffff:ffff:ffff:ffff
142ed4:d::/322ed4:d:ffff:ffff:ffff:ffff:ffff:ffff
152ed4:e::/322ed4:e:ffff:ffff:ffff:ffff:ffff:ffff
162ed4:f::/322ed4:f:ffff:ffff:ffff:ffff:ffff:ffff
172ed4:10::/322ed4:10:ffff:ffff:ffff:ffff:ffff:ffff
182ed4:11::/322ed4:11:ffff:ffff:ffff:ffff:ffff:ffff
192ed4:12::/322ed4:12:ffff:ffff:ffff:ffff:ffff:ffff
202ed4:13::/322ed4:13:ffff:ffff:ffff:ffff:ffff:ffff
212ed4:14::/322ed4:14:ffff:ffff:ffff:ffff:ffff:ffff
222ed4:15::/322ed4:15:ffff:ffff:ffff:ffff:ffff:ffff
232ed4:16::/322ed4:16:ffff:ffff:ffff:ffff:ffff:ffff
242ed4:17::/322ed4:17:ffff:ffff:ffff:ffff:ffff:ffff
252ed4:18::/322ed4:18:ffff:ffff:ffff:ffff:ffff:ffff
262ed4:19::/322ed4:19:ffff:ffff:ffff:ffff:ffff:ffff
272ed4:1a::/322ed4:1a:ffff:ffff:ffff:ffff:ffff:ffff
282ed4:1b::/322ed4:1b:ffff:ffff:ffff:ffff:ffff:ffff
292ed4:1c::/322ed4:1c:ffff:ffff:ffff:ffff:ffff:ffff
302ed4:1d::/322ed4:1d:ffff:ffff:ffff:ffff:ffff:ffff
312ed4:1e::/322ed4:1e:ffff:ffff:ffff:ffff:ffff:ffff
322ed4:1f::/322ed4:1f:ffff:ffff:ffff:ffff:ffff:ffff
332ed4:20::/322ed4:20:ffff:ffff:ffff:ffff:ffff:ffff
342ed4:21::/322ed4:21:ffff:ffff:ffff:ffff:ffff:ffff
352ed4:22::/322ed4:22:ffff:ffff:ffff:ffff:ffff:ffff
362ed4:23::/322ed4:23:ffff:ffff:ffff:ffff:ffff:ffff
372ed4:24::/322ed4:24:ffff:ffff:ffff:ffff:ffff:ffff
382ed4:25::/322ed4:25:ffff:ffff:ffff:ffff:ffff:ffff
392ed4:26::/322ed4:26:ffff:ffff:ffff:ffff:ffff:ffff
402ed4:27::/322ed4:27:ffff:ffff:ffff:ffff:ffff:ffff
412ed4:28::/322ed4:28:ffff:ffff:ffff:ffff:ffff:ffff
422ed4:29::/322ed4:29:ffff:ffff:ffff:ffff:ffff:ffff
432ed4:2a::/322ed4:2a:ffff:ffff:ffff:ffff:ffff:ffff
442ed4:2b::/322ed4:2b:ffff:ffff:ffff:ffff:ffff:ffff
452ed4:2c::/322ed4:2c:ffff:ffff:ffff:ffff:ffff:ffff
462ed4:2d::/322ed4:2d:ffff:ffff:ffff:ffff:ffff:ffff
472ed4:2e::/322ed4:2e:ffff:ffff:ffff:ffff:ffff:ffff
482ed4:2f::/322ed4:2f:ffff:ffff:ffff:ffff:ffff:ffff
492ed4:30::/322ed4:30:ffff:ffff:ffff:ffff:ffff:ffff
502ed4:31::/322ed4:31:ffff:ffff:ffff:ffff:ffff:ffff
512ed4:32::/322ed4:32:ffff:ffff:ffff:ffff:ffff:ffff
522ed4:33::/322ed4:33:ffff:ffff:ffff:ffff:ffff:ffff
532ed4:34::/322ed4:34:ffff:ffff:ffff:ffff:ffff:ffff
542ed4:35::/322ed4:35:ffff:ffff:ffff:ffff:ffff:ffff
552ed4:36::/322ed4:36:ffff:ffff:ffff:ffff:ffff:ffff
562ed4:37::/322ed4:37:ffff:ffff:ffff:ffff:ffff:ffff
572ed4:38::/322ed4:38:ffff:ffff:ffff:ffff:ffff:ffff
582ed4:39::/322ed4:39:ffff:ffff:ffff:ffff:ffff:ffff
592ed4:3a::/322ed4:3a:ffff:ffff:ffff:ffff:ffff:ffff
602ed4:3b::/322ed4:3b:ffff:ffff:ffff:ffff:ffff:ffff
612ed4:3c::/322ed4:3c:ffff:ffff:ffff:ffff:ffff:ffff
622ed4:3d::/322ed4:3d:ffff:ffff:ffff:ffff:ffff:ffff
632ed4:3e::/322ed4:3e:ffff:ffff:ffff:ffff:ffff:ffff
642ed4:3f::/322ed4:3f:ffff:ffff:ffff:ffff:ffff:ffff
652ed4:40::/322ed4:40:ffff:ffff:ffff:ffff:ffff:ffff
662ed4:41::/322ed4:41:ffff:ffff:ffff:ffff:ffff:ffff
672ed4:42::/322ed4:42:ffff:ffff:ffff:ffff:ffff:ffff
682ed4:43::/322ed4:43:ffff:ffff:ffff:ffff:ffff:ffff
692ed4:44::/322ed4:44:ffff:ffff:ffff:ffff:ffff:ffff
702ed4:45::/322ed4:45:ffff:ffff:ffff:ffff:ffff:ffff
712ed4:46::/322ed4:46:ffff:ffff:ffff:ffff:ffff:ffff
722ed4:47::/322ed4:47:ffff:ffff:ffff:ffff:ffff:ffff
732ed4:48::/322ed4:48:ffff:ffff:ffff:ffff:ffff:ffff
742ed4:49::/322ed4:49:ffff:ffff:ffff:ffff:ffff:ffff
752ed4:4a::/322ed4:4a:ffff:ffff:ffff:ffff:ffff:ffff
762ed4:4b::/322ed4:4b:ffff:ffff:ffff:ffff:ffff:ffff
772ed4:4c::/322ed4:4c:ffff:ffff:ffff:ffff:ffff:ffff
782ed4:4d::/322ed4:4d:ffff:ffff:ffff:ffff:ffff:ffff
792ed4:4e::/322ed4:4e:ffff:ffff:ffff:ffff:ffff:ffff
802ed4:4f::/322ed4:4f:ffff:ffff:ffff:ffff:ffff:ffff
812ed4:50::/322ed4:50:ffff:ffff:ffff:ffff:ffff:ffff
822ed4:51::/322ed4:51:ffff:ffff:ffff:ffff:ffff:ffff
832ed4:52::/322ed4:52:ffff:ffff:ffff:ffff:ffff:ffff
842ed4:53::/322ed4:53:ffff:ffff:ffff:ffff:ffff:ffff
852ed4:54::/322ed4:54:ffff:ffff:ffff:ffff:ffff:ffff
862ed4:55::/322ed4:55:ffff:ffff:ffff:ffff:ffff:ffff
872ed4:56::/322ed4:56:ffff:ffff:ffff:ffff:ffff:ffff
882ed4:57::/322ed4:57:ffff:ffff:ffff:ffff:ffff:ffff
892ed4:58::/322ed4:58:ffff:ffff:ffff:ffff:ffff:ffff
902ed4:59::/322ed4:59:ffff:ffff:ffff:ffff:ffff:ffff
912ed4:5a::/322ed4:5a:ffff:ffff:ffff:ffff:ffff:ffff
922ed4:5b::/322ed4:5b:ffff:ffff:ffff:ffff:ffff:ffff
932ed4:5c::/322ed4:5c:ffff:ffff:ffff:ffff:ffff:ffff
942ed4:5d::/322ed4:5d:ffff:ffff:ffff:ffff:ffff:ffff
952ed4:5e::/322ed4:5e:ffff:ffff:ffff:ffff:ffff:ffff
962ed4:5f::/322ed4:5f:ffff:ffff:ffff:ffff:ffff:ffff
972ed4:60::/322ed4:60:ffff:ffff:ffff:ffff:ffff:ffff
982ed4:61::/322ed4:61:ffff:ffff:ffff:ffff:ffff:ffff
992ed4:62::/322ed4:62:ffff:ffff:ffff:ffff:ffff:ffff
1002ed4:63::/322ed4:63:ffff:ffff:ffff:ffff:ffff:ffff
1012ed4:64::/322ed4:64:ffff:ffff:ffff:ffff:ffff:ffff
1022ed4:65::/322ed4:65:ffff:ffff:ffff:ffff:ffff:ffff
1032ed4:66::/322ed4:66:ffff:ffff:ffff:ffff:ffff:ffff
1042ed4:67::/322ed4:67:ffff:ffff:ffff:ffff:ffff:ffff
1052ed4:68::/322ed4:68:ffff:ffff:ffff:ffff:ffff:ffff
1062ed4:69::/322ed4:69:ffff:ffff:ffff:ffff:ffff:ffff
1072ed4:6a::/322ed4:6a:ffff:ffff:ffff:ffff:ffff:ffff
1082ed4:6b::/322ed4:6b:ffff:ffff:ffff:ffff:ffff:ffff
1092ed4:6c::/322ed4:6c:ffff:ffff:ffff:ffff:ffff:ffff
1102ed4:6d::/322ed4:6d:ffff:ffff:ffff:ffff:ffff:ffff
1112ed4:6e::/322ed4:6e:ffff:ffff:ffff:ffff:ffff:ffff
1122ed4:6f::/322ed4:6f:ffff:ffff:ffff:ffff:ffff:ffff
1132ed4:70::/322ed4:70:ffff:ffff:ffff:ffff:ffff:ffff
1142ed4:71::/322ed4:71:ffff:ffff:ffff:ffff:ffff:ffff
1152ed4:72::/322ed4:72:ffff:ffff:ffff:ffff:ffff:ffff
1162ed4:73::/322ed4:73:ffff:ffff:ffff:ffff:ffff:ffff
1172ed4:74::/322ed4:74:ffff:ffff:ffff:ffff:ffff:ffff
1182ed4:75::/322ed4:75:ffff:ffff:ffff:ffff:ffff:ffff
1192ed4:76::/322ed4:76:ffff:ffff:ffff:ffff:ffff:ffff
1202ed4:77::/322ed4:77:ffff:ffff:ffff:ffff:ffff:ffff
1212ed4:78::/322ed4:78:ffff:ffff:ffff:ffff:ffff:ffff
1222ed4:79::/322ed4:79:ffff:ffff:ffff:ffff:ffff:ffff
1232ed4:7a::/322ed4:7a:ffff:ffff:ffff:ffff:ffff:ffff
1242ed4:7b::/322ed4:7b:ffff:ffff:ffff:ffff:ffff:ffff
1252ed4:7c::/322ed4:7c:ffff:ffff:ffff:ffff:ffff:ffff
1262ed4:7d::/322ed4:7d:ffff:ffff:ffff:ffff:ffff:ffff
1272ed4:7e::/322ed4:7e:ffff:ffff:ffff:ffff:ffff:ffff
1282ed4:7f::/322ed4:7f:ffff:ffff:ffff:ffff:ffff:ffff
1292ed4:80::/322ed4:80:ffff:ffff:ffff:ffff:ffff:ffff
1302ed4:81::/322ed4:81:ffff:ffff:ffff:ffff:ffff:ffff
1312ed4:82::/322ed4:82:ffff:ffff:ffff:ffff:ffff:ffff
1322ed4:83::/322ed4:83:ffff:ffff:ffff:ffff:ffff:ffff
1332ed4:84::/322ed4:84:ffff:ffff:ffff:ffff:ffff:ffff
1342ed4:85::/322ed4:85:ffff:ffff:ffff:ffff:ffff:ffff
1352ed4:86::/322ed4:86:ffff:ffff:ffff:ffff:ffff:ffff
1362ed4:87::/322ed4:87:ffff:ffff:ffff:ffff:ffff:ffff
1372ed4:88::/322ed4:88:ffff:ffff:ffff:ffff:ffff:ffff
1382ed4:89::/322ed4:89:ffff:ffff:ffff:ffff:ffff:ffff
1392ed4:8a::/322ed4:8a:ffff:ffff:ffff:ffff:ffff:ffff
1402ed4:8b::/322ed4:8b:ffff:ffff:ffff:ffff:ffff:ffff
1412ed4:8c::/322ed4:8c:ffff:ffff:ffff:ffff:ffff:ffff
1422ed4:8d::/322ed4:8d:ffff:ffff:ffff:ffff:ffff:ffff
1432ed4:8e::/322ed4:8e:ffff:ffff:ffff:ffff:ffff:ffff
1442ed4:8f::/322ed4:8f:ffff:ffff:ffff:ffff:ffff:ffff
1452ed4:90::/322ed4:90:ffff:ffff:ffff:ffff:ffff:ffff
1462ed4:91::/322ed4:91:ffff:ffff:ffff:ffff:ffff:ffff
1472ed4:92::/322ed4:92:ffff:ffff:ffff:ffff:ffff:ffff
1482ed4:93::/322ed4:93:ffff:ffff:ffff:ffff:ffff:ffff
1492ed4:94::/322ed4:94:ffff:ffff:ffff:ffff:ffff:ffff
1502ed4:95::/322ed4:95:ffff:ffff:ffff:ffff:ffff:ffff
1512ed4:96::/322ed4:96:ffff:ffff:ffff:ffff:ffff:ffff
1522ed4:97::/322ed4:97:ffff:ffff:ffff:ffff:ffff:ffff
1532ed4:98::/322ed4:98:ffff:ffff:ffff:ffff:ffff:ffff
1542ed4:99::/322ed4:99:ffff:ffff:ffff:ffff:ffff:ffff
1552ed4:9a::/322ed4:9a:ffff:ffff:ffff:ffff:ffff:ffff
1562ed4:9b::/322ed4:9b:ffff:ffff:ffff:ffff:ffff:ffff
1572ed4:9c::/322ed4:9c:ffff:ffff:ffff:ffff:ffff:ffff
1582ed4:9d::/322ed4:9d:ffff:ffff:ffff:ffff:ffff:ffff
1592ed4:9e::/322ed4:9e:ffff:ffff:ffff:ffff:ffff:ffff
1602ed4:9f::/322ed4:9f:ffff:ffff:ffff:ffff:ffff:ffff
1612ed4:a0::/322ed4:a0:ffff:ffff:ffff:ffff:ffff:ffff
1622ed4:a1::/322ed4:a1:ffff:ffff:ffff:ffff:ffff:ffff
1632ed4:a2::/322ed4:a2:ffff:ffff:ffff:ffff:ffff:ffff
1642ed4:a3::/322ed4:a3:ffff:ffff:ffff:ffff:ffff:ffff
1652ed4:a4::/322ed4:a4:ffff:ffff:ffff:ffff:ffff:ffff
1662ed4:a5::/322ed4:a5:ffff:ffff:ffff:ffff:ffff:ffff
1672ed4:a6::/322ed4:a6:ffff:ffff:ffff:ffff:ffff:ffff
1682ed4:a7::/322ed4:a7:ffff:ffff:ffff:ffff:ffff:ffff
1692ed4:a8::/322ed4:a8:ffff:ffff:ffff:ffff:ffff:ffff
1702ed4:a9::/322ed4:a9:ffff:ffff:ffff:ffff:ffff:ffff
1712ed4:aa::/322ed4:aa:ffff:ffff:ffff:ffff:ffff:ffff
1722ed4:ab::/322ed4:ab:ffff:ffff:ffff:ffff:ffff:ffff
1732ed4:ac::/322ed4:ac:ffff:ffff:ffff:ffff:ffff:ffff
1742ed4:ad::/322ed4:ad:ffff:ffff:ffff:ffff:ffff:ffff
1752ed4:ae::/322ed4:ae:ffff:ffff:ffff:ffff:ffff:ffff
1762ed4:af::/322ed4:af:ffff:ffff:ffff:ffff:ffff:ffff
1772ed4:b0::/322ed4:b0:ffff:ffff:ffff:ffff:ffff:ffff
1782ed4:b1::/322ed4:b1:ffff:ffff:ffff:ffff:ffff:ffff
1792ed4:b2::/322ed4:b2:ffff:ffff:ffff:ffff:ffff:ffff
1802ed4:b3::/322ed4:b3:ffff:ffff:ffff:ffff:ffff:ffff
1812ed4:b4::/322ed4:b4:ffff:ffff:ffff:ffff:ffff:ffff
1822ed4:b5::/322ed4:b5:ffff:ffff:ffff:ffff:ffff:ffff
1832ed4:b6::/322ed4:b6:ffff:ffff:ffff:ffff:ffff:ffff
1842ed4:b7::/322ed4:b7:ffff:ffff:ffff:ffff:ffff:ffff
1852ed4:b8::/322ed4:b8:ffff:ffff:ffff:ffff:ffff:ffff
1862ed4:b9::/322ed4:b9:ffff:ffff:ffff:ffff:ffff:ffff
1872ed4:ba::/322ed4:ba:ffff:ffff:ffff:ffff:ffff:ffff
1882ed4:bb::/322ed4:bb:ffff:ffff:ffff:ffff:ffff:ffff
1892ed4:bc::/322ed4:bc:ffff:ffff:ffff:ffff:ffff:ffff
1902ed4:bd::/322ed4:bd:ffff:ffff:ffff:ffff:ffff:ffff
1912ed4:be::/322ed4:be:ffff:ffff:ffff:ffff:ffff:ffff
1922ed4:bf::/322ed4:bf:ffff:ffff:ffff:ffff:ffff:ffff
1932ed4:c0::/322ed4:c0:ffff:ffff:ffff:ffff:ffff:ffff
1942ed4:c1::/322ed4:c1:ffff:ffff:ffff:ffff:ffff:ffff
1952ed4:c2::/322ed4:c2:ffff:ffff:ffff:ffff:ffff:ffff
1962ed4:c3::/322ed4:c3:ffff:ffff:ffff:ffff:ffff:ffff
1972ed4:c4::/322ed4:c4:ffff:ffff:ffff:ffff:ffff:ffff
1982ed4:c5::/322ed4:c5:ffff:ffff:ffff:ffff:ffff:ffff
1992ed4:c6::/322ed4:c6:ffff:ffff:ffff:ffff:ffff:ffff
2002ed4:c7::/322ed4:c7:ffff:ffff:ffff:ffff:ffff:ffff
2012ed4:c8::/322ed4:c8:ffff:ffff:ffff:ffff:ffff:ffff
2022ed4:c9::/322ed4:c9:ffff:ffff:ffff:ffff:ffff:ffff
2032ed4:ca::/322ed4:ca:ffff:ffff:ffff:ffff:ffff:ffff
2042ed4:cb::/322ed4:cb:ffff:ffff:ffff:ffff:ffff:ffff
2052ed4:cc::/322ed4:cc:ffff:ffff:ffff:ffff:ffff:ffff
2062ed4:cd::/322ed4:cd:ffff:ffff:ffff:ffff:ffff:ffff
2072ed4:ce::/322ed4:ce:ffff:ffff:ffff:ffff:ffff:ffff
2082ed4:cf::/322ed4:cf:ffff:ffff:ffff:ffff:ffff:ffff
2092ed4:d0::/322ed4:d0:ffff:ffff:ffff:ffff:ffff:ffff
2102ed4:d1::/322ed4:d1:ffff:ffff:ffff:ffff:ffff:ffff
2112ed4:d2::/322ed4:d2:ffff:ffff:ffff:ffff:ffff:ffff
2122ed4:d3::/322ed4:d3:ffff:ffff:ffff:ffff:ffff:ffff
2132ed4:d4::/322ed4:d4:ffff:ffff:ffff:ffff:ffff:ffff
2142ed4:d5::/322ed4:d5:ffff:ffff:ffff:ffff:ffff:ffff
2152ed4:d6::/322ed4:d6:ffff:ffff:ffff:ffff:ffff:ffff
2162ed4:d7::/322ed4:d7:ffff:ffff:ffff:ffff:ffff:ffff
2172ed4:d8::/322ed4:d8:ffff:ffff:ffff:ffff:ffff:ffff
2182ed4:d9::/322ed4:d9:ffff:ffff:ffff:ffff:ffff:ffff
2192ed4:da::/322ed4:da:ffff:ffff:ffff:ffff:ffff:ffff
2202ed4:db::/322ed4:db:ffff:ffff:ffff:ffff:ffff:ffff
2212ed4:dc::/322ed4:dc:ffff:ffff:ffff:ffff:ffff:ffff
2222ed4:dd::/322ed4:dd:ffff:ffff:ffff:ffff:ffff:ffff
2232ed4:de::/322ed4:de:ffff:ffff:ffff:ffff:ffff:ffff
2242ed4:df::/322ed4:df:ffff:ffff:ffff:ffff:ffff:ffff
2252ed4:e0::/322ed4:e0:ffff:ffff:ffff:ffff:ffff:ffff
2262ed4:e1::/322ed4:e1:ffff:ffff:ffff:ffff:ffff:ffff
2272ed4:e2::/322ed4:e2:ffff:ffff:ffff:ffff:ffff:ffff
2282ed4:e3::/322ed4:e3:ffff:ffff:ffff:ffff:ffff:ffff
2292ed4:e4::/322ed4:e4:ffff:ffff:ffff:ffff:ffff:ffff
2302ed4:e5::/322ed4:e5:ffff:ffff:ffff:ffff:ffff:ffff
2312ed4:e6::/322ed4:e6:ffff:ffff:ffff:ffff:ffff:ffff
2322ed4:e7::/322ed4:e7:ffff:ffff:ffff:ffff:ffff:ffff
2332ed4:e8::/322ed4:e8:ffff:ffff:ffff:ffff:ffff:ffff
2342ed4:e9::/322ed4:e9:ffff:ffff:ffff:ffff:ffff:ffff
2352ed4:ea::/322ed4:ea:ffff:ffff:ffff:ffff:ffff:ffff
2362ed4:eb::/322ed4:eb:ffff:ffff:ffff:ffff:ffff:ffff
2372ed4:ec::/322ed4:ec:ffff:ffff:ffff:ffff:ffff:ffff
2382ed4:ed::/322ed4:ed:ffff:ffff:ffff:ffff:ffff:ffff
2392ed4:ee::/322ed4:ee:ffff:ffff:ffff:ffff:ffff:ffff
2402ed4:ef::/322ed4:ef:ffff:ffff:ffff:ffff:ffff:ffff
2412ed4:f0::/322ed4:f0:ffff:ffff:ffff:ffff:ffff:ffff
2422ed4:f1::/322ed4:f1:ffff:ffff:ffff:ffff:ffff:ffff
2432ed4:f2::/322ed4:f2:ffff:ffff:ffff:ffff:ffff:ffff
2442ed4:f3::/322ed4:f3:ffff:ffff:ffff:ffff:ffff:ffff
2452ed4:f4::/322ed4:f4:ffff:ffff:ffff:ffff:ffff:ffff
2462ed4:f5::/322ed4:f5:ffff:ffff:ffff:ffff:ffff:ffff
2472ed4:f6::/322ed4:f6:ffff:ffff:ffff:ffff:ffff:ffff
2482ed4:f7::/322ed4:f7:ffff:ffff:ffff:ffff:ffff:ffff
2492ed4:f8::/322ed4:f8:ffff:ffff:ffff:ffff:ffff:ffff
2502ed4:f9::/322ed4:f9:ffff:ffff:ffff:ffff:ffff:ffff
2512ed4:fa::/322ed4:fa:ffff:ffff:ffff:ffff:ffff:ffff
2522ed4:fb::/322ed4:fb:ffff:ffff:ffff:ffff:ffff:ffff
2532ed4:fc::/322ed4:fc:ffff:ffff:ffff:ffff:ffff:ffff
2542ed4:fd::/322ed4:fd:ffff:ffff:ffff:ffff:ffff:ffff
2552ed4:fe::/322ed4:fe:ffff:ffff:ffff:ffff:ffff:ffff
2562ed4:ff::/322ed4: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.