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Speed and call quality testTest delay, jitter and speed, with a focus on phone calls.My IP addressYour public IPv4 and IPv6 addresses, provider and address range.WhoIs lookupWho owns a domain or IP address, when it expires, and its DNS.DNS reportEvery DNS record for a domain, with email setup checked.IP subnet calculatorWork out a network's range, mask and hosts, and split it into subnets.

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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
2e2a::/16
First address
2e2a::
Last address
2e2a: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
2e2a:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
a.2.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)

2e2a::/16 makes 65,536 subnets of /32; the first 256 are listed.

Subnets
#SubnetLast address
12e2a::/322e2a:0:ffff:ffff:ffff:ffff:ffff:ffff
22e2a:1::/322e2a:1:ffff:ffff:ffff:ffff:ffff:ffff
32e2a:2::/322e2a:2:ffff:ffff:ffff:ffff:ffff:ffff
42e2a:3::/322e2a:3:ffff:ffff:ffff:ffff:ffff:ffff
52e2a:4::/322e2a:4:ffff:ffff:ffff:ffff:ffff:ffff
62e2a:5::/322e2a:5:ffff:ffff:ffff:ffff:ffff:ffff
72e2a:6::/322e2a:6:ffff:ffff:ffff:ffff:ffff:ffff
82e2a:7::/322e2a:7:ffff:ffff:ffff:ffff:ffff:ffff
92e2a:8::/322e2a:8:ffff:ffff:ffff:ffff:ffff:ffff
102e2a:9::/322e2a:9:ffff:ffff:ffff:ffff:ffff:ffff
112e2a:a::/322e2a:a:ffff:ffff:ffff:ffff:ffff:ffff
122e2a:b::/322e2a:b:ffff:ffff:ffff:ffff:ffff:ffff
132e2a:c::/322e2a:c:ffff:ffff:ffff:ffff:ffff:ffff
142e2a:d::/322e2a:d:ffff:ffff:ffff:ffff:ffff:ffff
152e2a:e::/322e2a:e:ffff:ffff:ffff:ffff:ffff:ffff
162e2a:f::/322e2a:f:ffff:ffff:ffff:ffff:ffff:ffff
172e2a:10::/322e2a:10:ffff:ffff:ffff:ffff:ffff:ffff
182e2a:11::/322e2a:11:ffff:ffff:ffff:ffff:ffff:ffff
192e2a:12::/322e2a:12:ffff:ffff:ffff:ffff:ffff:ffff
202e2a:13::/322e2a:13:ffff:ffff:ffff:ffff:ffff:ffff
212e2a:14::/322e2a:14:ffff:ffff:ffff:ffff:ffff:ffff
222e2a:15::/322e2a:15:ffff:ffff:ffff:ffff:ffff:ffff
232e2a:16::/322e2a:16:ffff:ffff:ffff:ffff:ffff:ffff
242e2a:17::/322e2a:17:ffff:ffff:ffff:ffff:ffff:ffff
252e2a:18::/322e2a:18:ffff:ffff:ffff:ffff:ffff:ffff
262e2a:19::/322e2a:19:ffff:ffff:ffff:ffff:ffff:ffff
272e2a:1a::/322e2a:1a:ffff:ffff:ffff:ffff:ffff:ffff
282e2a:1b::/322e2a:1b:ffff:ffff:ffff:ffff:ffff:ffff
292e2a:1c::/322e2a:1c:ffff:ffff:ffff:ffff:ffff:ffff
302e2a:1d::/322e2a:1d:ffff:ffff:ffff:ffff:ffff:ffff
312e2a:1e::/322e2a:1e:ffff:ffff:ffff:ffff:ffff:ffff
322e2a:1f::/322e2a:1f:ffff:ffff:ffff:ffff:ffff:ffff
332e2a:20::/322e2a:20:ffff:ffff:ffff:ffff:ffff:ffff
342e2a:21::/322e2a:21:ffff:ffff:ffff:ffff:ffff:ffff
352e2a:22::/322e2a:22:ffff:ffff:ffff:ffff:ffff:ffff
362e2a:23::/322e2a:23:ffff:ffff:ffff:ffff:ffff:ffff
372e2a:24::/322e2a:24:ffff:ffff:ffff:ffff:ffff:ffff
382e2a:25::/322e2a:25:ffff:ffff:ffff:ffff:ffff:ffff
392e2a:26::/322e2a:26:ffff:ffff:ffff:ffff:ffff:ffff
402e2a:27::/322e2a:27:ffff:ffff:ffff:ffff:ffff:ffff
412e2a:28::/322e2a:28:ffff:ffff:ffff:ffff:ffff:ffff
422e2a:29::/322e2a:29:ffff:ffff:ffff:ffff:ffff:ffff
432e2a:2a::/322e2a:2a:ffff:ffff:ffff:ffff:ffff:ffff
442e2a:2b::/322e2a:2b:ffff:ffff:ffff:ffff:ffff:ffff
452e2a:2c::/322e2a:2c:ffff:ffff:ffff:ffff:ffff:ffff
462e2a:2d::/322e2a:2d:ffff:ffff:ffff:ffff:ffff:ffff
472e2a:2e::/322e2a:2e:ffff:ffff:ffff:ffff:ffff:ffff
482e2a:2f::/322e2a:2f:ffff:ffff:ffff:ffff:ffff:ffff
492e2a:30::/322e2a:30:ffff:ffff:ffff:ffff:ffff:ffff
502e2a:31::/322e2a:31:ffff:ffff:ffff:ffff:ffff:ffff
512e2a:32::/322e2a:32:ffff:ffff:ffff:ffff:ffff:ffff
522e2a:33::/322e2a:33:ffff:ffff:ffff:ffff:ffff:ffff
532e2a:34::/322e2a:34:ffff:ffff:ffff:ffff:ffff:ffff
542e2a:35::/322e2a:35:ffff:ffff:ffff:ffff:ffff:ffff
552e2a:36::/322e2a:36:ffff:ffff:ffff:ffff:ffff:ffff
562e2a:37::/322e2a:37:ffff:ffff:ffff:ffff:ffff:ffff
572e2a:38::/322e2a:38:ffff:ffff:ffff:ffff:ffff:ffff
582e2a:39::/322e2a:39:ffff:ffff:ffff:ffff:ffff:ffff
592e2a:3a::/322e2a:3a:ffff:ffff:ffff:ffff:ffff:ffff
602e2a:3b::/322e2a:3b:ffff:ffff:ffff:ffff:ffff:ffff
612e2a:3c::/322e2a:3c:ffff:ffff:ffff:ffff:ffff:ffff
622e2a:3d::/322e2a:3d:ffff:ffff:ffff:ffff:ffff:ffff
632e2a:3e::/322e2a:3e:ffff:ffff:ffff:ffff:ffff:ffff
642e2a:3f::/322e2a:3f:ffff:ffff:ffff:ffff:ffff:ffff
652e2a:40::/322e2a:40:ffff:ffff:ffff:ffff:ffff:ffff
662e2a:41::/322e2a:41:ffff:ffff:ffff:ffff:ffff:ffff
672e2a:42::/322e2a:42:ffff:ffff:ffff:ffff:ffff:ffff
682e2a:43::/322e2a:43:ffff:ffff:ffff:ffff:ffff:ffff
692e2a:44::/322e2a:44:ffff:ffff:ffff:ffff:ffff:ffff
702e2a:45::/322e2a:45:ffff:ffff:ffff:ffff:ffff:ffff
712e2a:46::/322e2a:46:ffff:ffff:ffff:ffff:ffff:ffff
722e2a:47::/322e2a:47:ffff:ffff:ffff:ffff:ffff:ffff
732e2a:48::/322e2a:48:ffff:ffff:ffff:ffff:ffff:ffff
742e2a:49::/322e2a:49:ffff:ffff:ffff:ffff:ffff:ffff
752e2a:4a::/322e2a:4a:ffff:ffff:ffff:ffff:ffff:ffff
762e2a:4b::/322e2a:4b:ffff:ffff:ffff:ffff:ffff:ffff
772e2a:4c::/322e2a:4c:ffff:ffff:ffff:ffff:ffff:ffff
782e2a:4d::/322e2a:4d:ffff:ffff:ffff:ffff:ffff:ffff
792e2a:4e::/322e2a:4e:ffff:ffff:ffff:ffff:ffff:ffff
802e2a:4f::/322e2a:4f:ffff:ffff:ffff:ffff:ffff:ffff
812e2a:50::/322e2a:50:ffff:ffff:ffff:ffff:ffff:ffff
822e2a:51::/322e2a:51:ffff:ffff:ffff:ffff:ffff:ffff
832e2a:52::/322e2a:52:ffff:ffff:ffff:ffff:ffff:ffff
842e2a:53::/322e2a:53:ffff:ffff:ffff:ffff:ffff:ffff
852e2a:54::/322e2a:54:ffff:ffff:ffff:ffff:ffff:ffff
862e2a:55::/322e2a:55:ffff:ffff:ffff:ffff:ffff:ffff
872e2a:56::/322e2a:56:ffff:ffff:ffff:ffff:ffff:ffff
882e2a:57::/322e2a:57:ffff:ffff:ffff:ffff:ffff:ffff
892e2a:58::/322e2a:58:ffff:ffff:ffff:ffff:ffff:ffff
902e2a:59::/322e2a:59:ffff:ffff:ffff:ffff:ffff:ffff
912e2a:5a::/322e2a:5a:ffff:ffff:ffff:ffff:ffff:ffff
922e2a:5b::/322e2a:5b:ffff:ffff:ffff:ffff:ffff:ffff
932e2a:5c::/322e2a:5c:ffff:ffff:ffff:ffff:ffff:ffff
942e2a:5d::/322e2a:5d:ffff:ffff:ffff:ffff:ffff:ffff
952e2a:5e::/322e2a:5e:ffff:ffff:ffff:ffff:ffff:ffff
962e2a:5f::/322e2a:5f:ffff:ffff:ffff:ffff:ffff:ffff
972e2a:60::/322e2a:60:ffff:ffff:ffff:ffff:ffff:ffff
982e2a:61::/322e2a:61:ffff:ffff:ffff:ffff:ffff:ffff
992e2a:62::/322e2a:62:ffff:ffff:ffff:ffff:ffff:ffff
1002e2a:63::/322e2a:63:ffff:ffff:ffff:ffff:ffff:ffff
1012e2a:64::/322e2a:64:ffff:ffff:ffff:ffff:ffff:ffff
1022e2a:65::/322e2a:65:ffff:ffff:ffff:ffff:ffff:ffff
1032e2a:66::/322e2a:66:ffff:ffff:ffff:ffff:ffff:ffff
1042e2a:67::/322e2a:67:ffff:ffff:ffff:ffff:ffff:ffff
1052e2a:68::/322e2a:68:ffff:ffff:ffff:ffff:ffff:ffff
1062e2a:69::/322e2a:69:ffff:ffff:ffff:ffff:ffff:ffff
1072e2a:6a::/322e2a:6a:ffff:ffff:ffff:ffff:ffff:ffff
1082e2a:6b::/322e2a:6b:ffff:ffff:ffff:ffff:ffff:ffff
1092e2a:6c::/322e2a:6c:ffff:ffff:ffff:ffff:ffff:ffff
1102e2a:6d::/322e2a:6d:ffff:ffff:ffff:ffff:ffff:ffff
1112e2a:6e::/322e2a:6e:ffff:ffff:ffff:ffff:ffff:ffff
1122e2a:6f::/322e2a:6f:ffff:ffff:ffff:ffff:ffff:ffff
1132e2a:70::/322e2a:70:ffff:ffff:ffff:ffff:ffff:ffff
1142e2a:71::/322e2a:71:ffff:ffff:ffff:ffff:ffff:ffff
1152e2a:72::/322e2a:72:ffff:ffff:ffff:ffff:ffff:ffff
1162e2a:73::/322e2a:73:ffff:ffff:ffff:ffff:ffff:ffff
1172e2a:74::/322e2a:74:ffff:ffff:ffff:ffff:ffff:ffff
1182e2a:75::/322e2a:75:ffff:ffff:ffff:ffff:ffff:ffff
1192e2a:76::/322e2a:76:ffff:ffff:ffff:ffff:ffff:ffff
1202e2a:77::/322e2a:77:ffff:ffff:ffff:ffff:ffff:ffff
1212e2a:78::/322e2a:78:ffff:ffff:ffff:ffff:ffff:ffff
1222e2a:79::/322e2a:79:ffff:ffff:ffff:ffff:ffff:ffff
1232e2a:7a::/322e2a:7a:ffff:ffff:ffff:ffff:ffff:ffff
1242e2a:7b::/322e2a:7b:ffff:ffff:ffff:ffff:ffff:ffff
1252e2a:7c::/322e2a:7c:ffff:ffff:ffff:ffff:ffff:ffff
1262e2a:7d::/322e2a:7d:ffff:ffff:ffff:ffff:ffff:ffff
1272e2a:7e::/322e2a:7e:ffff:ffff:ffff:ffff:ffff:ffff
1282e2a:7f::/322e2a:7f:ffff:ffff:ffff:ffff:ffff:ffff
1292e2a:80::/322e2a:80:ffff:ffff:ffff:ffff:ffff:ffff
1302e2a:81::/322e2a:81:ffff:ffff:ffff:ffff:ffff:ffff
1312e2a:82::/322e2a:82:ffff:ffff:ffff:ffff:ffff:ffff
1322e2a:83::/322e2a:83:ffff:ffff:ffff:ffff:ffff:ffff
1332e2a:84::/322e2a:84:ffff:ffff:ffff:ffff:ffff:ffff
1342e2a:85::/322e2a:85:ffff:ffff:ffff:ffff:ffff:ffff
1352e2a:86::/322e2a:86:ffff:ffff:ffff:ffff:ffff:ffff
1362e2a:87::/322e2a:87:ffff:ffff:ffff:ffff:ffff:ffff
1372e2a:88::/322e2a:88:ffff:ffff:ffff:ffff:ffff:ffff
1382e2a:89::/322e2a:89:ffff:ffff:ffff:ffff:ffff:ffff
1392e2a:8a::/322e2a:8a:ffff:ffff:ffff:ffff:ffff:ffff
1402e2a:8b::/322e2a:8b:ffff:ffff:ffff:ffff:ffff:ffff
1412e2a:8c::/322e2a:8c:ffff:ffff:ffff:ffff:ffff:ffff
1422e2a:8d::/322e2a:8d:ffff:ffff:ffff:ffff:ffff:ffff
1432e2a:8e::/322e2a:8e:ffff:ffff:ffff:ffff:ffff:ffff
1442e2a:8f::/322e2a:8f:ffff:ffff:ffff:ffff:ffff:ffff
1452e2a:90::/322e2a:90:ffff:ffff:ffff:ffff:ffff:ffff
1462e2a:91::/322e2a:91:ffff:ffff:ffff:ffff:ffff:ffff
1472e2a:92::/322e2a:92:ffff:ffff:ffff:ffff:ffff:ffff
1482e2a:93::/322e2a:93:ffff:ffff:ffff:ffff:ffff:ffff
1492e2a:94::/322e2a:94:ffff:ffff:ffff:ffff:ffff:ffff
1502e2a:95::/322e2a:95:ffff:ffff:ffff:ffff:ffff:ffff
1512e2a:96::/322e2a:96:ffff:ffff:ffff:ffff:ffff:ffff
1522e2a:97::/322e2a:97:ffff:ffff:ffff:ffff:ffff:ffff
1532e2a:98::/322e2a:98:ffff:ffff:ffff:ffff:ffff:ffff
1542e2a:99::/322e2a:99:ffff:ffff:ffff:ffff:ffff:ffff
1552e2a:9a::/322e2a:9a:ffff:ffff:ffff:ffff:ffff:ffff
1562e2a:9b::/322e2a:9b:ffff:ffff:ffff:ffff:ffff:ffff
1572e2a:9c::/322e2a:9c:ffff:ffff:ffff:ffff:ffff:ffff
1582e2a:9d::/322e2a:9d:ffff:ffff:ffff:ffff:ffff:ffff
1592e2a:9e::/322e2a:9e:ffff:ffff:ffff:ffff:ffff:ffff
1602e2a:9f::/322e2a:9f:ffff:ffff:ffff:ffff:ffff:ffff
1612e2a:a0::/322e2a:a0:ffff:ffff:ffff:ffff:ffff:ffff
1622e2a:a1::/322e2a:a1:ffff:ffff:ffff:ffff:ffff:ffff
1632e2a:a2::/322e2a:a2:ffff:ffff:ffff:ffff:ffff:ffff
1642e2a:a3::/322e2a:a3:ffff:ffff:ffff:ffff:ffff:ffff
1652e2a:a4::/322e2a:a4:ffff:ffff:ffff:ffff:ffff:ffff
1662e2a:a5::/322e2a:a5:ffff:ffff:ffff:ffff:ffff:ffff
1672e2a:a6::/322e2a:a6:ffff:ffff:ffff:ffff:ffff:ffff
1682e2a:a7::/322e2a:a7:ffff:ffff:ffff:ffff:ffff:ffff
1692e2a:a8::/322e2a:a8:ffff:ffff:ffff:ffff:ffff:ffff
1702e2a:a9::/322e2a:a9:ffff:ffff:ffff:ffff:ffff:ffff
1712e2a:aa::/322e2a:aa:ffff:ffff:ffff:ffff:ffff:ffff
1722e2a:ab::/322e2a:ab:ffff:ffff:ffff:ffff:ffff:ffff
1732e2a:ac::/322e2a:ac:ffff:ffff:ffff:ffff:ffff:ffff
1742e2a:ad::/322e2a:ad:ffff:ffff:ffff:ffff:ffff:ffff
1752e2a:ae::/322e2a:ae:ffff:ffff:ffff:ffff:ffff:ffff
1762e2a:af::/322e2a:af:ffff:ffff:ffff:ffff:ffff:ffff
1772e2a:b0::/322e2a:b0:ffff:ffff:ffff:ffff:ffff:ffff
1782e2a:b1::/322e2a:b1:ffff:ffff:ffff:ffff:ffff:ffff
1792e2a:b2::/322e2a:b2:ffff:ffff:ffff:ffff:ffff:ffff
1802e2a:b3::/322e2a:b3:ffff:ffff:ffff:ffff:ffff:ffff
1812e2a:b4::/322e2a:b4:ffff:ffff:ffff:ffff:ffff:ffff
1822e2a:b5::/322e2a:b5:ffff:ffff:ffff:ffff:ffff:ffff
1832e2a:b6::/322e2a:b6:ffff:ffff:ffff:ffff:ffff:ffff
1842e2a:b7::/322e2a:b7:ffff:ffff:ffff:ffff:ffff:ffff
1852e2a:b8::/322e2a:b8:ffff:ffff:ffff:ffff:ffff:ffff
1862e2a:b9::/322e2a:b9:ffff:ffff:ffff:ffff:ffff:ffff
1872e2a:ba::/322e2a:ba:ffff:ffff:ffff:ffff:ffff:ffff
1882e2a:bb::/322e2a:bb:ffff:ffff:ffff:ffff:ffff:ffff
1892e2a:bc::/322e2a:bc:ffff:ffff:ffff:ffff:ffff:ffff
1902e2a:bd::/322e2a:bd:ffff:ffff:ffff:ffff:ffff:ffff
1912e2a:be::/322e2a:be:ffff:ffff:ffff:ffff:ffff:ffff
1922e2a:bf::/322e2a:bf:ffff:ffff:ffff:ffff:ffff:ffff
1932e2a:c0::/322e2a:c0:ffff:ffff:ffff:ffff:ffff:ffff
1942e2a:c1::/322e2a:c1:ffff:ffff:ffff:ffff:ffff:ffff
1952e2a:c2::/322e2a:c2:ffff:ffff:ffff:ffff:ffff:ffff
1962e2a:c3::/322e2a:c3:ffff:ffff:ffff:ffff:ffff:ffff
1972e2a:c4::/322e2a:c4:ffff:ffff:ffff:ffff:ffff:ffff
1982e2a:c5::/322e2a:c5:ffff:ffff:ffff:ffff:ffff:ffff
1992e2a:c6::/322e2a:c6:ffff:ffff:ffff:ffff:ffff:ffff
2002e2a:c7::/322e2a:c7:ffff:ffff:ffff:ffff:ffff:ffff
2012e2a:c8::/322e2a:c8:ffff:ffff:ffff:ffff:ffff:ffff
2022e2a:c9::/322e2a:c9:ffff:ffff:ffff:ffff:ffff:ffff
2032e2a:ca::/322e2a:ca:ffff:ffff:ffff:ffff:ffff:ffff
2042e2a:cb::/322e2a:cb:ffff:ffff:ffff:ffff:ffff:ffff
2052e2a:cc::/322e2a:cc:ffff:ffff:ffff:ffff:ffff:ffff
2062e2a:cd::/322e2a:cd:ffff:ffff:ffff:ffff:ffff:ffff
2072e2a:ce::/322e2a:ce:ffff:ffff:ffff:ffff:ffff:ffff
2082e2a:cf::/322e2a:cf:ffff:ffff:ffff:ffff:ffff:ffff
2092e2a:d0::/322e2a:d0:ffff:ffff:ffff:ffff:ffff:ffff
2102e2a:d1::/322e2a:d1:ffff:ffff:ffff:ffff:ffff:ffff
2112e2a:d2::/322e2a:d2:ffff:ffff:ffff:ffff:ffff:ffff
2122e2a:d3::/322e2a:d3:ffff:ffff:ffff:ffff:ffff:ffff
2132e2a:d4::/322e2a:d4:ffff:ffff:ffff:ffff:ffff:ffff
2142e2a:d5::/322e2a:d5:ffff:ffff:ffff:ffff:ffff:ffff
2152e2a:d6::/322e2a:d6:ffff:ffff:ffff:ffff:ffff:ffff
2162e2a:d7::/322e2a:d7:ffff:ffff:ffff:ffff:ffff:ffff
2172e2a:d8::/322e2a:d8:ffff:ffff:ffff:ffff:ffff:ffff
2182e2a:d9::/322e2a:d9:ffff:ffff:ffff:ffff:ffff:ffff
2192e2a:da::/322e2a:da:ffff:ffff:ffff:ffff:ffff:ffff
2202e2a:db::/322e2a:db:ffff:ffff:ffff:ffff:ffff:ffff
2212e2a:dc::/322e2a:dc:ffff:ffff:ffff:ffff:ffff:ffff
2222e2a:dd::/322e2a:dd:ffff:ffff:ffff:ffff:ffff:ffff
2232e2a:de::/322e2a:de:ffff:ffff:ffff:ffff:ffff:ffff
2242e2a:df::/322e2a:df:ffff:ffff:ffff:ffff:ffff:ffff
2252e2a:e0::/322e2a:e0:ffff:ffff:ffff:ffff:ffff:ffff
2262e2a:e1::/322e2a:e1:ffff:ffff:ffff:ffff:ffff:ffff
2272e2a:e2::/322e2a:e2:ffff:ffff:ffff:ffff:ffff:ffff
2282e2a:e3::/322e2a:e3:ffff:ffff:ffff:ffff:ffff:ffff
2292e2a:e4::/322e2a:e4:ffff:ffff:ffff:ffff:ffff:ffff
2302e2a:e5::/322e2a:e5:ffff:ffff:ffff:ffff:ffff:ffff
2312e2a:e6::/322e2a:e6:ffff:ffff:ffff:ffff:ffff:ffff
2322e2a:e7::/322e2a:e7:ffff:ffff:ffff:ffff:ffff:ffff
2332e2a:e8::/322e2a:e8:ffff:ffff:ffff:ffff:ffff:ffff
2342e2a:e9::/322e2a:e9:ffff:ffff:ffff:ffff:ffff:ffff
2352e2a:ea::/322e2a:ea:ffff:ffff:ffff:ffff:ffff:ffff
2362e2a:eb::/322e2a:eb:ffff:ffff:ffff:ffff:ffff:ffff
2372e2a:ec::/322e2a:ec:ffff:ffff:ffff:ffff:ffff:ffff
2382e2a:ed::/322e2a:ed:ffff:ffff:ffff:ffff:ffff:ffff
2392e2a:ee::/322e2a:ee:ffff:ffff:ffff:ffff:ffff:ffff
2402e2a:ef::/322e2a:ef:ffff:ffff:ffff:ffff:ffff:ffff
2412e2a:f0::/322e2a:f0:ffff:ffff:ffff:ffff:ffff:ffff
2422e2a:f1::/322e2a:f1:ffff:ffff:ffff:ffff:ffff:ffff
2432e2a:f2::/322e2a:f2:ffff:ffff:ffff:ffff:ffff:ffff
2442e2a:f3::/322e2a:f3:ffff:ffff:ffff:ffff:ffff:ffff
2452e2a:f4::/322e2a:f4:ffff:ffff:ffff:ffff:ffff:ffff
2462e2a:f5::/322e2a:f5:ffff:ffff:ffff:ffff:ffff:ffff
2472e2a:f6::/322e2a:f6:ffff:ffff:ffff:ffff:ffff:ffff
2482e2a:f7::/322e2a:f7:ffff:ffff:ffff:ffff:ffff:ffff
2492e2a:f8::/322e2a:f8:ffff:ffff:ffff:ffff:ffff:ffff
2502e2a:f9::/322e2a:f9:ffff:ffff:ffff:ffff:ffff:ffff
2512e2a:fa::/322e2a:fa:ffff:ffff:ffff:ffff:ffff:ffff
2522e2a:fb::/322e2a:fb:ffff:ffff:ffff:ffff:ffff:ffff
2532e2a:fc::/322e2a:fc:ffff:ffff:ffff:ffff:ffff:ffff
2542e2a:fd::/322e2a:fd:ffff:ffff:ffff:ffff:ffff:ffff
2552e2a:fe::/322e2a:fe:ffff:ffff:ffff:ffff:ffff:ffff
2562e2a:ff::/322e2a: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.