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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
2e49::/16
First address
2e49::
Last address
2e49: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
2e49:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
9.4.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)

2e49::/16 makes 65,536 subnets of /32; the first 256 are listed.

Subnets
#SubnetLast address
12e49::/322e49:0:ffff:ffff:ffff:ffff:ffff:ffff
22e49:1::/322e49:1:ffff:ffff:ffff:ffff:ffff:ffff
32e49:2::/322e49:2:ffff:ffff:ffff:ffff:ffff:ffff
42e49:3::/322e49:3:ffff:ffff:ffff:ffff:ffff:ffff
52e49:4::/322e49:4:ffff:ffff:ffff:ffff:ffff:ffff
62e49:5::/322e49:5:ffff:ffff:ffff:ffff:ffff:ffff
72e49:6::/322e49:6:ffff:ffff:ffff:ffff:ffff:ffff
82e49:7::/322e49:7:ffff:ffff:ffff:ffff:ffff:ffff
92e49:8::/322e49:8:ffff:ffff:ffff:ffff:ffff:ffff
102e49:9::/322e49:9:ffff:ffff:ffff:ffff:ffff:ffff
112e49:a::/322e49:a:ffff:ffff:ffff:ffff:ffff:ffff
122e49:b::/322e49:b:ffff:ffff:ffff:ffff:ffff:ffff
132e49:c::/322e49:c:ffff:ffff:ffff:ffff:ffff:ffff
142e49:d::/322e49:d:ffff:ffff:ffff:ffff:ffff:ffff
152e49:e::/322e49:e:ffff:ffff:ffff:ffff:ffff:ffff
162e49:f::/322e49:f:ffff:ffff:ffff:ffff:ffff:ffff
172e49:10::/322e49:10:ffff:ffff:ffff:ffff:ffff:ffff
182e49:11::/322e49:11:ffff:ffff:ffff:ffff:ffff:ffff
192e49:12::/322e49:12:ffff:ffff:ffff:ffff:ffff:ffff
202e49:13::/322e49:13:ffff:ffff:ffff:ffff:ffff:ffff
212e49:14::/322e49:14:ffff:ffff:ffff:ffff:ffff:ffff
222e49:15::/322e49:15:ffff:ffff:ffff:ffff:ffff:ffff
232e49:16::/322e49:16:ffff:ffff:ffff:ffff:ffff:ffff
242e49:17::/322e49:17:ffff:ffff:ffff:ffff:ffff:ffff
252e49:18::/322e49:18:ffff:ffff:ffff:ffff:ffff:ffff
262e49:19::/322e49:19:ffff:ffff:ffff:ffff:ffff:ffff
272e49:1a::/322e49:1a:ffff:ffff:ffff:ffff:ffff:ffff
282e49:1b::/322e49:1b:ffff:ffff:ffff:ffff:ffff:ffff
292e49:1c::/322e49:1c:ffff:ffff:ffff:ffff:ffff:ffff
302e49:1d::/322e49:1d:ffff:ffff:ffff:ffff:ffff:ffff
312e49:1e::/322e49:1e:ffff:ffff:ffff:ffff:ffff:ffff
322e49:1f::/322e49:1f:ffff:ffff:ffff:ffff:ffff:ffff
332e49:20::/322e49:20:ffff:ffff:ffff:ffff:ffff:ffff
342e49:21::/322e49:21:ffff:ffff:ffff:ffff:ffff:ffff
352e49:22::/322e49:22:ffff:ffff:ffff:ffff:ffff:ffff
362e49:23::/322e49:23:ffff:ffff:ffff:ffff:ffff:ffff
372e49:24::/322e49:24:ffff:ffff:ffff:ffff:ffff:ffff
382e49:25::/322e49:25:ffff:ffff:ffff:ffff:ffff:ffff
392e49:26::/322e49:26:ffff:ffff:ffff:ffff:ffff:ffff
402e49:27::/322e49:27:ffff:ffff:ffff:ffff:ffff:ffff
412e49:28::/322e49:28:ffff:ffff:ffff:ffff:ffff:ffff
422e49:29::/322e49:29:ffff:ffff:ffff:ffff:ffff:ffff
432e49:2a::/322e49:2a:ffff:ffff:ffff:ffff:ffff:ffff
442e49:2b::/322e49:2b:ffff:ffff:ffff:ffff:ffff:ffff
452e49:2c::/322e49:2c:ffff:ffff:ffff:ffff:ffff:ffff
462e49:2d::/322e49:2d:ffff:ffff:ffff:ffff:ffff:ffff
472e49:2e::/322e49:2e:ffff:ffff:ffff:ffff:ffff:ffff
482e49:2f::/322e49:2f:ffff:ffff:ffff:ffff:ffff:ffff
492e49:30::/322e49:30:ffff:ffff:ffff:ffff:ffff:ffff
502e49:31::/322e49:31:ffff:ffff:ffff:ffff:ffff:ffff
512e49:32::/322e49:32:ffff:ffff:ffff:ffff:ffff:ffff
522e49:33::/322e49:33:ffff:ffff:ffff:ffff:ffff:ffff
532e49:34::/322e49:34:ffff:ffff:ffff:ffff:ffff:ffff
542e49:35::/322e49:35:ffff:ffff:ffff:ffff:ffff:ffff
552e49:36::/322e49:36:ffff:ffff:ffff:ffff:ffff:ffff
562e49:37::/322e49:37:ffff:ffff:ffff:ffff:ffff:ffff
572e49:38::/322e49:38:ffff:ffff:ffff:ffff:ffff:ffff
582e49:39::/322e49:39:ffff:ffff:ffff:ffff:ffff:ffff
592e49:3a::/322e49:3a:ffff:ffff:ffff:ffff:ffff:ffff
602e49:3b::/322e49:3b:ffff:ffff:ffff:ffff:ffff:ffff
612e49:3c::/322e49:3c:ffff:ffff:ffff:ffff:ffff:ffff
622e49:3d::/322e49:3d:ffff:ffff:ffff:ffff:ffff:ffff
632e49:3e::/322e49:3e:ffff:ffff:ffff:ffff:ffff:ffff
642e49:3f::/322e49:3f:ffff:ffff:ffff:ffff:ffff:ffff
652e49:40::/322e49:40:ffff:ffff:ffff:ffff:ffff:ffff
662e49:41::/322e49:41:ffff:ffff:ffff:ffff:ffff:ffff
672e49:42::/322e49:42:ffff:ffff:ffff:ffff:ffff:ffff
682e49:43::/322e49:43:ffff:ffff:ffff:ffff:ffff:ffff
692e49:44::/322e49:44:ffff:ffff:ffff:ffff:ffff:ffff
702e49:45::/322e49:45:ffff:ffff:ffff:ffff:ffff:ffff
712e49:46::/322e49:46:ffff:ffff:ffff:ffff:ffff:ffff
722e49:47::/322e49:47:ffff:ffff:ffff:ffff:ffff:ffff
732e49:48::/322e49:48:ffff:ffff:ffff:ffff:ffff:ffff
742e49:49::/322e49:49:ffff:ffff:ffff:ffff:ffff:ffff
752e49:4a::/322e49:4a:ffff:ffff:ffff:ffff:ffff:ffff
762e49:4b::/322e49:4b:ffff:ffff:ffff:ffff:ffff:ffff
772e49:4c::/322e49:4c:ffff:ffff:ffff:ffff:ffff:ffff
782e49:4d::/322e49:4d:ffff:ffff:ffff:ffff:ffff:ffff
792e49:4e::/322e49:4e:ffff:ffff:ffff:ffff:ffff:ffff
802e49:4f::/322e49:4f:ffff:ffff:ffff:ffff:ffff:ffff
812e49:50::/322e49:50:ffff:ffff:ffff:ffff:ffff:ffff
822e49:51::/322e49:51:ffff:ffff:ffff:ffff:ffff:ffff
832e49:52::/322e49:52:ffff:ffff:ffff:ffff:ffff:ffff
842e49:53::/322e49:53:ffff:ffff:ffff:ffff:ffff:ffff
852e49:54::/322e49:54:ffff:ffff:ffff:ffff:ffff:ffff
862e49:55::/322e49:55:ffff:ffff:ffff:ffff:ffff:ffff
872e49:56::/322e49:56:ffff:ffff:ffff:ffff:ffff:ffff
882e49:57::/322e49:57:ffff:ffff:ffff:ffff:ffff:ffff
892e49:58::/322e49:58:ffff:ffff:ffff:ffff:ffff:ffff
902e49:59::/322e49:59:ffff:ffff:ffff:ffff:ffff:ffff
912e49:5a::/322e49:5a:ffff:ffff:ffff:ffff:ffff:ffff
922e49:5b::/322e49:5b:ffff:ffff:ffff:ffff:ffff:ffff
932e49:5c::/322e49:5c:ffff:ffff:ffff:ffff:ffff:ffff
942e49:5d::/322e49:5d:ffff:ffff:ffff:ffff:ffff:ffff
952e49:5e::/322e49:5e:ffff:ffff:ffff:ffff:ffff:ffff
962e49:5f::/322e49:5f:ffff:ffff:ffff:ffff:ffff:ffff
972e49:60::/322e49:60:ffff:ffff:ffff:ffff:ffff:ffff
982e49:61::/322e49:61:ffff:ffff:ffff:ffff:ffff:ffff
992e49:62::/322e49:62:ffff:ffff:ffff:ffff:ffff:ffff
1002e49:63::/322e49:63:ffff:ffff:ffff:ffff:ffff:ffff
1012e49:64::/322e49:64:ffff:ffff:ffff:ffff:ffff:ffff
1022e49:65::/322e49:65:ffff:ffff:ffff:ffff:ffff:ffff
1032e49:66::/322e49:66:ffff:ffff:ffff:ffff:ffff:ffff
1042e49:67::/322e49:67:ffff:ffff:ffff:ffff:ffff:ffff
1052e49:68::/322e49:68:ffff:ffff:ffff:ffff:ffff:ffff
1062e49:69::/322e49:69:ffff:ffff:ffff:ffff:ffff:ffff
1072e49:6a::/322e49:6a:ffff:ffff:ffff:ffff:ffff:ffff
1082e49:6b::/322e49:6b:ffff:ffff:ffff:ffff:ffff:ffff
1092e49:6c::/322e49:6c:ffff:ffff:ffff:ffff:ffff:ffff
1102e49:6d::/322e49:6d:ffff:ffff:ffff:ffff:ffff:ffff
1112e49:6e::/322e49:6e:ffff:ffff:ffff:ffff:ffff:ffff
1122e49:6f::/322e49:6f:ffff:ffff:ffff:ffff:ffff:ffff
1132e49:70::/322e49:70:ffff:ffff:ffff:ffff:ffff:ffff
1142e49:71::/322e49:71:ffff:ffff:ffff:ffff:ffff:ffff
1152e49:72::/322e49:72:ffff:ffff:ffff:ffff:ffff:ffff
1162e49:73::/322e49:73:ffff:ffff:ffff:ffff:ffff:ffff
1172e49:74::/322e49:74:ffff:ffff:ffff:ffff:ffff:ffff
1182e49:75::/322e49:75:ffff:ffff:ffff:ffff:ffff:ffff
1192e49:76::/322e49:76:ffff:ffff:ffff:ffff:ffff:ffff
1202e49:77::/322e49:77:ffff:ffff:ffff:ffff:ffff:ffff
1212e49:78::/322e49:78:ffff:ffff:ffff:ffff:ffff:ffff
1222e49:79::/322e49:79:ffff:ffff:ffff:ffff:ffff:ffff
1232e49:7a::/322e49:7a:ffff:ffff:ffff:ffff:ffff:ffff
1242e49:7b::/322e49:7b:ffff:ffff:ffff:ffff:ffff:ffff
1252e49:7c::/322e49:7c:ffff:ffff:ffff:ffff:ffff:ffff
1262e49:7d::/322e49:7d:ffff:ffff:ffff:ffff:ffff:ffff
1272e49:7e::/322e49:7e:ffff:ffff:ffff:ffff:ffff:ffff
1282e49:7f::/322e49:7f:ffff:ffff:ffff:ffff:ffff:ffff
1292e49:80::/322e49:80:ffff:ffff:ffff:ffff:ffff:ffff
1302e49:81::/322e49:81:ffff:ffff:ffff:ffff:ffff:ffff
1312e49:82::/322e49:82:ffff:ffff:ffff:ffff:ffff:ffff
1322e49:83::/322e49:83:ffff:ffff:ffff:ffff:ffff:ffff
1332e49:84::/322e49:84:ffff:ffff:ffff:ffff:ffff:ffff
1342e49:85::/322e49:85:ffff:ffff:ffff:ffff:ffff:ffff
1352e49:86::/322e49:86:ffff:ffff:ffff:ffff:ffff:ffff
1362e49:87::/322e49:87:ffff:ffff:ffff:ffff:ffff:ffff
1372e49:88::/322e49:88:ffff:ffff:ffff:ffff:ffff:ffff
1382e49:89::/322e49:89:ffff:ffff:ffff:ffff:ffff:ffff
1392e49:8a::/322e49:8a:ffff:ffff:ffff:ffff:ffff:ffff
1402e49:8b::/322e49:8b:ffff:ffff:ffff:ffff:ffff:ffff
1412e49:8c::/322e49:8c:ffff:ffff:ffff:ffff:ffff:ffff
1422e49:8d::/322e49:8d:ffff:ffff:ffff:ffff:ffff:ffff
1432e49:8e::/322e49:8e:ffff:ffff:ffff:ffff:ffff:ffff
1442e49:8f::/322e49:8f:ffff:ffff:ffff:ffff:ffff:ffff
1452e49:90::/322e49:90:ffff:ffff:ffff:ffff:ffff:ffff
1462e49:91::/322e49:91:ffff:ffff:ffff:ffff:ffff:ffff
1472e49:92::/322e49:92:ffff:ffff:ffff:ffff:ffff:ffff
1482e49:93::/322e49:93:ffff:ffff:ffff:ffff:ffff:ffff
1492e49:94::/322e49:94:ffff:ffff:ffff:ffff:ffff:ffff
1502e49:95::/322e49:95:ffff:ffff:ffff:ffff:ffff:ffff
1512e49:96::/322e49:96:ffff:ffff:ffff:ffff:ffff:ffff
1522e49:97::/322e49:97:ffff:ffff:ffff:ffff:ffff:ffff
1532e49:98::/322e49:98:ffff:ffff:ffff:ffff:ffff:ffff
1542e49:99::/322e49:99:ffff:ffff:ffff:ffff:ffff:ffff
1552e49:9a::/322e49:9a:ffff:ffff:ffff:ffff:ffff:ffff
1562e49:9b::/322e49:9b:ffff:ffff:ffff:ffff:ffff:ffff
1572e49:9c::/322e49:9c:ffff:ffff:ffff:ffff:ffff:ffff
1582e49:9d::/322e49:9d:ffff:ffff:ffff:ffff:ffff:ffff
1592e49:9e::/322e49:9e:ffff:ffff:ffff:ffff:ffff:ffff
1602e49:9f::/322e49:9f:ffff:ffff:ffff:ffff:ffff:ffff
1612e49:a0::/322e49:a0:ffff:ffff:ffff:ffff:ffff:ffff
1622e49:a1::/322e49:a1:ffff:ffff:ffff:ffff:ffff:ffff
1632e49:a2::/322e49:a2:ffff:ffff:ffff:ffff:ffff:ffff
1642e49:a3::/322e49:a3:ffff:ffff:ffff:ffff:ffff:ffff
1652e49:a4::/322e49:a4:ffff:ffff:ffff:ffff:ffff:ffff
1662e49:a5::/322e49:a5:ffff:ffff:ffff:ffff:ffff:ffff
1672e49:a6::/322e49:a6:ffff:ffff:ffff:ffff:ffff:ffff
1682e49:a7::/322e49:a7:ffff:ffff:ffff:ffff:ffff:ffff
1692e49:a8::/322e49:a8:ffff:ffff:ffff:ffff:ffff:ffff
1702e49:a9::/322e49:a9:ffff:ffff:ffff:ffff:ffff:ffff
1712e49:aa::/322e49:aa:ffff:ffff:ffff:ffff:ffff:ffff
1722e49:ab::/322e49:ab:ffff:ffff:ffff:ffff:ffff:ffff
1732e49:ac::/322e49:ac:ffff:ffff:ffff:ffff:ffff:ffff
1742e49:ad::/322e49:ad:ffff:ffff:ffff:ffff:ffff:ffff
1752e49:ae::/322e49:ae:ffff:ffff:ffff:ffff:ffff:ffff
1762e49:af::/322e49:af:ffff:ffff:ffff:ffff:ffff:ffff
1772e49:b0::/322e49:b0:ffff:ffff:ffff:ffff:ffff:ffff
1782e49:b1::/322e49:b1:ffff:ffff:ffff:ffff:ffff:ffff
1792e49:b2::/322e49:b2:ffff:ffff:ffff:ffff:ffff:ffff
1802e49:b3::/322e49:b3:ffff:ffff:ffff:ffff:ffff:ffff
1812e49:b4::/322e49:b4:ffff:ffff:ffff:ffff:ffff:ffff
1822e49:b5::/322e49:b5:ffff:ffff:ffff:ffff:ffff:ffff
1832e49:b6::/322e49:b6:ffff:ffff:ffff:ffff:ffff:ffff
1842e49:b7::/322e49:b7:ffff:ffff:ffff:ffff:ffff:ffff
1852e49:b8::/322e49:b8:ffff:ffff:ffff:ffff:ffff:ffff
1862e49:b9::/322e49:b9:ffff:ffff:ffff:ffff:ffff:ffff
1872e49:ba::/322e49:ba:ffff:ffff:ffff:ffff:ffff:ffff
1882e49:bb::/322e49:bb:ffff:ffff:ffff:ffff:ffff:ffff
1892e49:bc::/322e49:bc:ffff:ffff:ffff:ffff:ffff:ffff
1902e49:bd::/322e49:bd:ffff:ffff:ffff:ffff:ffff:ffff
1912e49:be::/322e49:be:ffff:ffff:ffff:ffff:ffff:ffff
1922e49:bf::/322e49:bf:ffff:ffff:ffff:ffff:ffff:ffff
1932e49:c0::/322e49:c0:ffff:ffff:ffff:ffff:ffff:ffff
1942e49:c1::/322e49:c1:ffff:ffff:ffff:ffff:ffff:ffff
1952e49:c2::/322e49:c2:ffff:ffff:ffff:ffff:ffff:ffff
1962e49:c3::/322e49:c3:ffff:ffff:ffff:ffff:ffff:ffff
1972e49:c4::/322e49:c4:ffff:ffff:ffff:ffff:ffff:ffff
1982e49:c5::/322e49:c5:ffff:ffff:ffff:ffff:ffff:ffff
1992e49:c6::/322e49:c6:ffff:ffff:ffff:ffff:ffff:ffff
2002e49:c7::/322e49:c7:ffff:ffff:ffff:ffff:ffff:ffff
2012e49:c8::/322e49:c8:ffff:ffff:ffff:ffff:ffff:ffff
2022e49:c9::/322e49:c9:ffff:ffff:ffff:ffff:ffff:ffff
2032e49:ca::/322e49:ca:ffff:ffff:ffff:ffff:ffff:ffff
2042e49:cb::/322e49:cb:ffff:ffff:ffff:ffff:ffff:ffff
2052e49:cc::/322e49:cc:ffff:ffff:ffff:ffff:ffff:ffff
2062e49:cd::/322e49:cd:ffff:ffff:ffff:ffff:ffff:ffff
2072e49:ce::/322e49:ce:ffff:ffff:ffff:ffff:ffff:ffff
2082e49:cf::/322e49:cf:ffff:ffff:ffff:ffff:ffff:ffff
2092e49:d0::/322e49:d0:ffff:ffff:ffff:ffff:ffff:ffff
2102e49:d1::/322e49:d1:ffff:ffff:ffff:ffff:ffff:ffff
2112e49:d2::/322e49:d2:ffff:ffff:ffff:ffff:ffff:ffff
2122e49:d3::/322e49:d3:ffff:ffff:ffff:ffff:ffff:ffff
2132e49:d4::/322e49:d4:ffff:ffff:ffff:ffff:ffff:ffff
2142e49:d5::/322e49:d5:ffff:ffff:ffff:ffff:ffff:ffff
2152e49:d6::/322e49:d6:ffff:ffff:ffff:ffff:ffff:ffff
2162e49:d7::/322e49:d7:ffff:ffff:ffff:ffff:ffff:ffff
2172e49:d8::/322e49:d8:ffff:ffff:ffff:ffff:ffff:ffff
2182e49:d9::/322e49:d9:ffff:ffff:ffff:ffff:ffff:ffff
2192e49:da::/322e49:da:ffff:ffff:ffff:ffff:ffff:ffff
2202e49:db::/322e49:db:ffff:ffff:ffff:ffff:ffff:ffff
2212e49:dc::/322e49:dc:ffff:ffff:ffff:ffff:ffff:ffff
2222e49:dd::/322e49:dd:ffff:ffff:ffff:ffff:ffff:ffff
2232e49:de::/322e49:de:ffff:ffff:ffff:ffff:ffff:ffff
2242e49:df::/322e49:df:ffff:ffff:ffff:ffff:ffff:ffff
2252e49:e0::/322e49:e0:ffff:ffff:ffff:ffff:ffff:ffff
2262e49:e1::/322e49:e1:ffff:ffff:ffff:ffff:ffff:ffff
2272e49:e2::/322e49:e2:ffff:ffff:ffff:ffff:ffff:ffff
2282e49:e3::/322e49:e3:ffff:ffff:ffff:ffff:ffff:ffff
2292e49:e4::/322e49:e4:ffff:ffff:ffff:ffff:ffff:ffff
2302e49:e5::/322e49:e5:ffff:ffff:ffff:ffff:ffff:ffff
2312e49:e6::/322e49:e6:ffff:ffff:ffff:ffff:ffff:ffff
2322e49:e7::/322e49:e7:ffff:ffff:ffff:ffff:ffff:ffff
2332e49:e8::/322e49:e8:ffff:ffff:ffff:ffff:ffff:ffff
2342e49:e9::/322e49:e9:ffff:ffff:ffff:ffff:ffff:ffff
2352e49:ea::/322e49:ea:ffff:ffff:ffff:ffff:ffff:ffff
2362e49:eb::/322e49:eb:ffff:ffff:ffff:ffff:ffff:ffff
2372e49:ec::/322e49:ec:ffff:ffff:ffff:ffff:ffff:ffff
2382e49:ed::/322e49:ed:ffff:ffff:ffff:ffff:ffff:ffff
2392e49:ee::/322e49:ee:ffff:ffff:ffff:ffff:ffff:ffff
2402e49:ef::/322e49:ef:ffff:ffff:ffff:ffff:ffff:ffff
2412e49:f0::/322e49:f0:ffff:ffff:ffff:ffff:ffff:ffff
2422e49:f1::/322e49:f1:ffff:ffff:ffff:ffff:ffff:ffff
2432e49:f2::/322e49:f2:ffff:ffff:ffff:ffff:ffff:ffff
2442e49:f3::/322e49:f3:ffff:ffff:ffff:ffff:ffff:ffff
2452e49:f4::/322e49:f4:ffff:ffff:ffff:ffff:ffff:ffff
2462e49:f5::/322e49:f5:ffff:ffff:ffff:ffff:ffff:ffff
2472e49:f6::/322e49:f6:ffff:ffff:ffff:ffff:ffff:ffff
2482e49:f7::/322e49:f7:ffff:ffff:ffff:ffff:ffff:ffff
2492e49:f8::/322e49:f8:ffff:ffff:ffff:ffff:ffff:ffff
2502e49:f9::/322e49:f9:ffff:ffff:ffff:ffff:ffff:ffff
2512e49:fa::/322e49:fa:ffff:ffff:ffff:ffff:ffff:ffff
2522e49:fb::/322e49:fb:ffff:ffff:ffff:ffff:ffff:ffff
2532e49:fc::/322e49:fc:ffff:ffff:ffff:ffff:ffff:ffff
2542e49:fd::/322e49:fd:ffff:ffff:ffff:ffff:ffff:ffff
2552e49:fe::/322e49:fe:ffff:ffff:ffff:ffff:ffff:ffff
2562e49:ff::/322e49: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.