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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
2eb2::/16
First address
2eb2::
Last address
2eb2: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
2eb2:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
2.b.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)

2eb2::/16 makes 65,536 subnets of /32; the first 256 are listed.

Subnets
#SubnetLast address
12eb2::/322eb2:0:ffff:ffff:ffff:ffff:ffff:ffff
22eb2:1::/322eb2:1:ffff:ffff:ffff:ffff:ffff:ffff
32eb2:2::/322eb2:2:ffff:ffff:ffff:ffff:ffff:ffff
42eb2:3::/322eb2:3:ffff:ffff:ffff:ffff:ffff:ffff
52eb2:4::/322eb2:4:ffff:ffff:ffff:ffff:ffff:ffff
62eb2:5::/322eb2:5:ffff:ffff:ffff:ffff:ffff:ffff
72eb2:6::/322eb2:6:ffff:ffff:ffff:ffff:ffff:ffff
82eb2:7::/322eb2:7:ffff:ffff:ffff:ffff:ffff:ffff
92eb2:8::/322eb2:8:ffff:ffff:ffff:ffff:ffff:ffff
102eb2:9::/322eb2:9:ffff:ffff:ffff:ffff:ffff:ffff
112eb2:a::/322eb2:a:ffff:ffff:ffff:ffff:ffff:ffff
122eb2:b::/322eb2:b:ffff:ffff:ffff:ffff:ffff:ffff
132eb2:c::/322eb2:c:ffff:ffff:ffff:ffff:ffff:ffff
142eb2:d::/322eb2:d:ffff:ffff:ffff:ffff:ffff:ffff
152eb2:e::/322eb2:e:ffff:ffff:ffff:ffff:ffff:ffff
162eb2:f::/322eb2:f:ffff:ffff:ffff:ffff:ffff:ffff
172eb2:10::/322eb2:10:ffff:ffff:ffff:ffff:ffff:ffff
182eb2:11::/322eb2:11:ffff:ffff:ffff:ffff:ffff:ffff
192eb2:12::/322eb2:12:ffff:ffff:ffff:ffff:ffff:ffff
202eb2:13::/322eb2:13:ffff:ffff:ffff:ffff:ffff:ffff
212eb2:14::/322eb2:14:ffff:ffff:ffff:ffff:ffff:ffff
222eb2:15::/322eb2:15:ffff:ffff:ffff:ffff:ffff:ffff
232eb2:16::/322eb2:16:ffff:ffff:ffff:ffff:ffff:ffff
242eb2:17::/322eb2:17:ffff:ffff:ffff:ffff:ffff:ffff
252eb2:18::/322eb2:18:ffff:ffff:ffff:ffff:ffff:ffff
262eb2:19::/322eb2:19:ffff:ffff:ffff:ffff:ffff:ffff
272eb2:1a::/322eb2:1a:ffff:ffff:ffff:ffff:ffff:ffff
282eb2:1b::/322eb2:1b:ffff:ffff:ffff:ffff:ffff:ffff
292eb2:1c::/322eb2:1c:ffff:ffff:ffff:ffff:ffff:ffff
302eb2:1d::/322eb2:1d:ffff:ffff:ffff:ffff:ffff:ffff
312eb2:1e::/322eb2:1e:ffff:ffff:ffff:ffff:ffff:ffff
322eb2:1f::/322eb2:1f:ffff:ffff:ffff:ffff:ffff:ffff
332eb2:20::/322eb2:20:ffff:ffff:ffff:ffff:ffff:ffff
342eb2:21::/322eb2:21:ffff:ffff:ffff:ffff:ffff:ffff
352eb2:22::/322eb2:22:ffff:ffff:ffff:ffff:ffff:ffff
362eb2:23::/322eb2:23:ffff:ffff:ffff:ffff:ffff:ffff
372eb2:24::/322eb2:24:ffff:ffff:ffff:ffff:ffff:ffff
382eb2:25::/322eb2:25:ffff:ffff:ffff:ffff:ffff:ffff
392eb2:26::/322eb2:26:ffff:ffff:ffff:ffff:ffff:ffff
402eb2:27::/322eb2:27:ffff:ffff:ffff:ffff:ffff:ffff
412eb2:28::/322eb2:28:ffff:ffff:ffff:ffff:ffff:ffff
422eb2:29::/322eb2:29:ffff:ffff:ffff:ffff:ffff:ffff
432eb2:2a::/322eb2:2a:ffff:ffff:ffff:ffff:ffff:ffff
442eb2:2b::/322eb2:2b:ffff:ffff:ffff:ffff:ffff:ffff
452eb2:2c::/322eb2:2c:ffff:ffff:ffff:ffff:ffff:ffff
462eb2:2d::/322eb2:2d:ffff:ffff:ffff:ffff:ffff:ffff
472eb2:2e::/322eb2:2e:ffff:ffff:ffff:ffff:ffff:ffff
482eb2:2f::/322eb2:2f:ffff:ffff:ffff:ffff:ffff:ffff
492eb2:30::/322eb2:30:ffff:ffff:ffff:ffff:ffff:ffff
502eb2:31::/322eb2:31:ffff:ffff:ffff:ffff:ffff:ffff
512eb2:32::/322eb2:32:ffff:ffff:ffff:ffff:ffff:ffff
522eb2:33::/322eb2:33:ffff:ffff:ffff:ffff:ffff:ffff
532eb2:34::/322eb2:34:ffff:ffff:ffff:ffff:ffff:ffff
542eb2:35::/322eb2:35:ffff:ffff:ffff:ffff:ffff:ffff
552eb2:36::/322eb2:36:ffff:ffff:ffff:ffff:ffff:ffff
562eb2:37::/322eb2:37:ffff:ffff:ffff:ffff:ffff:ffff
572eb2:38::/322eb2:38:ffff:ffff:ffff:ffff:ffff:ffff
582eb2:39::/322eb2:39:ffff:ffff:ffff:ffff:ffff:ffff
592eb2:3a::/322eb2:3a:ffff:ffff:ffff:ffff:ffff:ffff
602eb2:3b::/322eb2:3b:ffff:ffff:ffff:ffff:ffff:ffff
612eb2:3c::/322eb2:3c:ffff:ffff:ffff:ffff:ffff:ffff
622eb2:3d::/322eb2:3d:ffff:ffff:ffff:ffff:ffff:ffff
632eb2:3e::/322eb2:3e:ffff:ffff:ffff:ffff:ffff:ffff
642eb2:3f::/322eb2:3f:ffff:ffff:ffff:ffff:ffff:ffff
652eb2:40::/322eb2:40:ffff:ffff:ffff:ffff:ffff:ffff
662eb2:41::/322eb2:41:ffff:ffff:ffff:ffff:ffff:ffff
672eb2:42::/322eb2:42:ffff:ffff:ffff:ffff:ffff:ffff
682eb2:43::/322eb2:43:ffff:ffff:ffff:ffff:ffff:ffff
692eb2:44::/322eb2:44:ffff:ffff:ffff:ffff:ffff:ffff
702eb2:45::/322eb2:45:ffff:ffff:ffff:ffff:ffff:ffff
712eb2:46::/322eb2:46:ffff:ffff:ffff:ffff:ffff:ffff
722eb2:47::/322eb2:47:ffff:ffff:ffff:ffff:ffff:ffff
732eb2:48::/322eb2:48:ffff:ffff:ffff:ffff:ffff:ffff
742eb2:49::/322eb2:49:ffff:ffff:ffff:ffff:ffff:ffff
752eb2:4a::/322eb2:4a:ffff:ffff:ffff:ffff:ffff:ffff
762eb2:4b::/322eb2:4b:ffff:ffff:ffff:ffff:ffff:ffff
772eb2:4c::/322eb2:4c:ffff:ffff:ffff:ffff:ffff:ffff
782eb2:4d::/322eb2:4d:ffff:ffff:ffff:ffff:ffff:ffff
792eb2:4e::/322eb2:4e:ffff:ffff:ffff:ffff:ffff:ffff
802eb2:4f::/322eb2:4f:ffff:ffff:ffff:ffff:ffff:ffff
812eb2:50::/322eb2:50:ffff:ffff:ffff:ffff:ffff:ffff
822eb2:51::/322eb2:51:ffff:ffff:ffff:ffff:ffff:ffff
832eb2:52::/322eb2:52:ffff:ffff:ffff:ffff:ffff:ffff
842eb2:53::/322eb2:53:ffff:ffff:ffff:ffff:ffff:ffff
852eb2:54::/322eb2:54:ffff:ffff:ffff:ffff:ffff:ffff
862eb2:55::/322eb2:55:ffff:ffff:ffff:ffff:ffff:ffff
872eb2:56::/322eb2:56:ffff:ffff:ffff:ffff:ffff:ffff
882eb2:57::/322eb2:57:ffff:ffff:ffff:ffff:ffff:ffff
892eb2:58::/322eb2:58:ffff:ffff:ffff:ffff:ffff:ffff
902eb2:59::/322eb2:59:ffff:ffff:ffff:ffff:ffff:ffff
912eb2:5a::/322eb2:5a:ffff:ffff:ffff:ffff:ffff:ffff
922eb2:5b::/322eb2:5b:ffff:ffff:ffff:ffff:ffff:ffff
932eb2:5c::/322eb2:5c:ffff:ffff:ffff:ffff:ffff:ffff
942eb2:5d::/322eb2:5d:ffff:ffff:ffff:ffff:ffff:ffff
952eb2:5e::/322eb2:5e:ffff:ffff:ffff:ffff:ffff:ffff
962eb2:5f::/322eb2:5f:ffff:ffff:ffff:ffff:ffff:ffff
972eb2:60::/322eb2:60:ffff:ffff:ffff:ffff:ffff:ffff
982eb2:61::/322eb2:61:ffff:ffff:ffff:ffff:ffff:ffff
992eb2:62::/322eb2:62:ffff:ffff:ffff:ffff:ffff:ffff
1002eb2:63::/322eb2:63:ffff:ffff:ffff:ffff:ffff:ffff
1012eb2:64::/322eb2:64:ffff:ffff:ffff:ffff:ffff:ffff
1022eb2:65::/322eb2:65:ffff:ffff:ffff:ffff:ffff:ffff
1032eb2:66::/322eb2:66:ffff:ffff:ffff:ffff:ffff:ffff
1042eb2:67::/322eb2:67:ffff:ffff:ffff:ffff:ffff:ffff
1052eb2:68::/322eb2:68:ffff:ffff:ffff:ffff:ffff:ffff
1062eb2:69::/322eb2:69:ffff:ffff:ffff:ffff:ffff:ffff
1072eb2:6a::/322eb2:6a:ffff:ffff:ffff:ffff:ffff:ffff
1082eb2:6b::/322eb2:6b:ffff:ffff:ffff:ffff:ffff:ffff
1092eb2:6c::/322eb2:6c:ffff:ffff:ffff:ffff:ffff:ffff
1102eb2:6d::/322eb2:6d:ffff:ffff:ffff:ffff:ffff:ffff
1112eb2:6e::/322eb2:6e:ffff:ffff:ffff:ffff:ffff:ffff
1122eb2:6f::/322eb2:6f:ffff:ffff:ffff:ffff:ffff:ffff
1132eb2:70::/322eb2:70:ffff:ffff:ffff:ffff:ffff:ffff
1142eb2:71::/322eb2:71:ffff:ffff:ffff:ffff:ffff:ffff
1152eb2:72::/322eb2:72:ffff:ffff:ffff:ffff:ffff:ffff
1162eb2:73::/322eb2:73:ffff:ffff:ffff:ffff:ffff:ffff
1172eb2:74::/322eb2:74:ffff:ffff:ffff:ffff:ffff:ffff
1182eb2:75::/322eb2:75:ffff:ffff:ffff:ffff:ffff:ffff
1192eb2:76::/322eb2:76:ffff:ffff:ffff:ffff:ffff:ffff
1202eb2:77::/322eb2:77:ffff:ffff:ffff:ffff:ffff:ffff
1212eb2:78::/322eb2:78:ffff:ffff:ffff:ffff:ffff:ffff
1222eb2:79::/322eb2:79:ffff:ffff:ffff:ffff:ffff:ffff
1232eb2:7a::/322eb2:7a:ffff:ffff:ffff:ffff:ffff:ffff
1242eb2:7b::/322eb2:7b:ffff:ffff:ffff:ffff:ffff:ffff
1252eb2:7c::/322eb2:7c:ffff:ffff:ffff:ffff:ffff:ffff
1262eb2:7d::/322eb2:7d:ffff:ffff:ffff:ffff:ffff:ffff
1272eb2:7e::/322eb2:7e:ffff:ffff:ffff:ffff:ffff:ffff
1282eb2:7f::/322eb2:7f:ffff:ffff:ffff:ffff:ffff:ffff
1292eb2:80::/322eb2:80:ffff:ffff:ffff:ffff:ffff:ffff
1302eb2:81::/322eb2:81:ffff:ffff:ffff:ffff:ffff:ffff
1312eb2:82::/322eb2:82:ffff:ffff:ffff:ffff:ffff:ffff
1322eb2:83::/322eb2:83:ffff:ffff:ffff:ffff:ffff:ffff
1332eb2:84::/322eb2:84:ffff:ffff:ffff:ffff:ffff:ffff
1342eb2:85::/322eb2:85:ffff:ffff:ffff:ffff:ffff:ffff
1352eb2:86::/322eb2:86:ffff:ffff:ffff:ffff:ffff:ffff
1362eb2:87::/322eb2:87:ffff:ffff:ffff:ffff:ffff:ffff
1372eb2:88::/322eb2:88:ffff:ffff:ffff:ffff:ffff:ffff
1382eb2:89::/322eb2:89:ffff:ffff:ffff:ffff:ffff:ffff
1392eb2:8a::/322eb2:8a:ffff:ffff:ffff:ffff:ffff:ffff
1402eb2:8b::/322eb2:8b:ffff:ffff:ffff:ffff:ffff:ffff
1412eb2:8c::/322eb2:8c:ffff:ffff:ffff:ffff:ffff:ffff
1422eb2:8d::/322eb2:8d:ffff:ffff:ffff:ffff:ffff:ffff
1432eb2:8e::/322eb2:8e:ffff:ffff:ffff:ffff:ffff:ffff
1442eb2:8f::/322eb2:8f:ffff:ffff:ffff:ffff:ffff:ffff
1452eb2:90::/322eb2:90:ffff:ffff:ffff:ffff:ffff:ffff
1462eb2:91::/322eb2:91:ffff:ffff:ffff:ffff:ffff:ffff
1472eb2:92::/322eb2:92:ffff:ffff:ffff:ffff:ffff:ffff
1482eb2:93::/322eb2:93:ffff:ffff:ffff:ffff:ffff:ffff
1492eb2:94::/322eb2:94:ffff:ffff:ffff:ffff:ffff:ffff
1502eb2:95::/322eb2:95:ffff:ffff:ffff:ffff:ffff:ffff
1512eb2:96::/322eb2:96:ffff:ffff:ffff:ffff:ffff:ffff
1522eb2:97::/322eb2:97:ffff:ffff:ffff:ffff:ffff:ffff
1532eb2:98::/322eb2:98:ffff:ffff:ffff:ffff:ffff:ffff
1542eb2:99::/322eb2:99:ffff:ffff:ffff:ffff:ffff:ffff
1552eb2:9a::/322eb2:9a:ffff:ffff:ffff:ffff:ffff:ffff
1562eb2:9b::/322eb2:9b:ffff:ffff:ffff:ffff:ffff:ffff
1572eb2:9c::/322eb2:9c:ffff:ffff:ffff:ffff:ffff:ffff
1582eb2:9d::/322eb2:9d:ffff:ffff:ffff:ffff:ffff:ffff
1592eb2:9e::/322eb2:9e:ffff:ffff:ffff:ffff:ffff:ffff
1602eb2:9f::/322eb2:9f:ffff:ffff:ffff:ffff:ffff:ffff
1612eb2:a0::/322eb2:a0:ffff:ffff:ffff:ffff:ffff:ffff
1622eb2:a1::/322eb2:a1:ffff:ffff:ffff:ffff:ffff:ffff
1632eb2:a2::/322eb2:a2:ffff:ffff:ffff:ffff:ffff:ffff
1642eb2:a3::/322eb2:a3:ffff:ffff:ffff:ffff:ffff:ffff
1652eb2:a4::/322eb2:a4:ffff:ffff:ffff:ffff:ffff:ffff
1662eb2:a5::/322eb2:a5:ffff:ffff:ffff:ffff:ffff:ffff
1672eb2:a6::/322eb2:a6:ffff:ffff:ffff:ffff:ffff:ffff
1682eb2:a7::/322eb2:a7:ffff:ffff:ffff:ffff:ffff:ffff
1692eb2:a8::/322eb2:a8:ffff:ffff:ffff:ffff:ffff:ffff
1702eb2:a9::/322eb2:a9:ffff:ffff:ffff:ffff:ffff:ffff
1712eb2:aa::/322eb2:aa:ffff:ffff:ffff:ffff:ffff:ffff
1722eb2:ab::/322eb2:ab:ffff:ffff:ffff:ffff:ffff:ffff
1732eb2:ac::/322eb2:ac:ffff:ffff:ffff:ffff:ffff:ffff
1742eb2:ad::/322eb2:ad:ffff:ffff:ffff:ffff:ffff:ffff
1752eb2:ae::/322eb2:ae:ffff:ffff:ffff:ffff:ffff:ffff
1762eb2:af::/322eb2:af:ffff:ffff:ffff:ffff:ffff:ffff
1772eb2:b0::/322eb2:b0:ffff:ffff:ffff:ffff:ffff:ffff
1782eb2:b1::/322eb2:b1:ffff:ffff:ffff:ffff:ffff:ffff
1792eb2:b2::/322eb2:b2:ffff:ffff:ffff:ffff:ffff:ffff
1802eb2:b3::/322eb2:b3:ffff:ffff:ffff:ffff:ffff:ffff
1812eb2:b4::/322eb2:b4:ffff:ffff:ffff:ffff:ffff:ffff
1822eb2:b5::/322eb2:b5:ffff:ffff:ffff:ffff:ffff:ffff
1832eb2:b6::/322eb2:b6:ffff:ffff:ffff:ffff:ffff:ffff
1842eb2:b7::/322eb2:b7:ffff:ffff:ffff:ffff:ffff:ffff
1852eb2:b8::/322eb2:b8:ffff:ffff:ffff:ffff:ffff:ffff
1862eb2:b9::/322eb2:b9:ffff:ffff:ffff:ffff:ffff:ffff
1872eb2:ba::/322eb2:ba:ffff:ffff:ffff:ffff:ffff:ffff
1882eb2:bb::/322eb2:bb:ffff:ffff:ffff:ffff:ffff:ffff
1892eb2:bc::/322eb2:bc:ffff:ffff:ffff:ffff:ffff:ffff
1902eb2:bd::/322eb2:bd:ffff:ffff:ffff:ffff:ffff:ffff
1912eb2:be::/322eb2:be:ffff:ffff:ffff:ffff:ffff:ffff
1922eb2:bf::/322eb2:bf:ffff:ffff:ffff:ffff:ffff:ffff
1932eb2:c0::/322eb2:c0:ffff:ffff:ffff:ffff:ffff:ffff
1942eb2:c1::/322eb2:c1:ffff:ffff:ffff:ffff:ffff:ffff
1952eb2:c2::/322eb2:c2:ffff:ffff:ffff:ffff:ffff:ffff
1962eb2:c3::/322eb2:c3:ffff:ffff:ffff:ffff:ffff:ffff
1972eb2:c4::/322eb2:c4:ffff:ffff:ffff:ffff:ffff:ffff
1982eb2:c5::/322eb2:c5:ffff:ffff:ffff:ffff:ffff:ffff
1992eb2:c6::/322eb2:c6:ffff:ffff:ffff:ffff:ffff:ffff
2002eb2:c7::/322eb2:c7:ffff:ffff:ffff:ffff:ffff:ffff
2012eb2:c8::/322eb2:c8:ffff:ffff:ffff:ffff:ffff:ffff
2022eb2:c9::/322eb2:c9:ffff:ffff:ffff:ffff:ffff:ffff
2032eb2:ca::/322eb2:ca:ffff:ffff:ffff:ffff:ffff:ffff
2042eb2:cb::/322eb2:cb:ffff:ffff:ffff:ffff:ffff:ffff
2052eb2:cc::/322eb2:cc:ffff:ffff:ffff:ffff:ffff:ffff
2062eb2:cd::/322eb2:cd:ffff:ffff:ffff:ffff:ffff:ffff
2072eb2:ce::/322eb2:ce:ffff:ffff:ffff:ffff:ffff:ffff
2082eb2:cf::/322eb2:cf:ffff:ffff:ffff:ffff:ffff:ffff
2092eb2:d0::/322eb2:d0:ffff:ffff:ffff:ffff:ffff:ffff
2102eb2:d1::/322eb2:d1:ffff:ffff:ffff:ffff:ffff:ffff
2112eb2:d2::/322eb2:d2:ffff:ffff:ffff:ffff:ffff:ffff
2122eb2:d3::/322eb2:d3:ffff:ffff:ffff:ffff:ffff:ffff
2132eb2:d4::/322eb2:d4:ffff:ffff:ffff:ffff:ffff:ffff
2142eb2:d5::/322eb2:d5:ffff:ffff:ffff:ffff:ffff:ffff
2152eb2:d6::/322eb2:d6:ffff:ffff:ffff:ffff:ffff:ffff
2162eb2:d7::/322eb2:d7:ffff:ffff:ffff:ffff:ffff:ffff
2172eb2:d8::/322eb2:d8:ffff:ffff:ffff:ffff:ffff:ffff
2182eb2:d9::/322eb2:d9:ffff:ffff:ffff:ffff:ffff:ffff
2192eb2:da::/322eb2:da:ffff:ffff:ffff:ffff:ffff:ffff
2202eb2:db::/322eb2:db:ffff:ffff:ffff:ffff:ffff:ffff
2212eb2:dc::/322eb2:dc:ffff:ffff:ffff:ffff:ffff:ffff
2222eb2:dd::/322eb2:dd:ffff:ffff:ffff:ffff:ffff:ffff
2232eb2:de::/322eb2:de:ffff:ffff:ffff:ffff:ffff:ffff
2242eb2:df::/322eb2:df:ffff:ffff:ffff:ffff:ffff:ffff
2252eb2:e0::/322eb2:e0:ffff:ffff:ffff:ffff:ffff:ffff
2262eb2:e1::/322eb2:e1:ffff:ffff:ffff:ffff:ffff:ffff
2272eb2:e2::/322eb2:e2:ffff:ffff:ffff:ffff:ffff:ffff
2282eb2:e3::/322eb2:e3:ffff:ffff:ffff:ffff:ffff:ffff
2292eb2:e4::/322eb2:e4:ffff:ffff:ffff:ffff:ffff:ffff
2302eb2:e5::/322eb2:e5:ffff:ffff:ffff:ffff:ffff:ffff
2312eb2:e6::/322eb2:e6:ffff:ffff:ffff:ffff:ffff:ffff
2322eb2:e7::/322eb2:e7:ffff:ffff:ffff:ffff:ffff:ffff
2332eb2:e8::/322eb2:e8:ffff:ffff:ffff:ffff:ffff:ffff
2342eb2:e9::/322eb2:e9:ffff:ffff:ffff:ffff:ffff:ffff
2352eb2:ea::/322eb2:ea:ffff:ffff:ffff:ffff:ffff:ffff
2362eb2:eb::/322eb2:eb:ffff:ffff:ffff:ffff:ffff:ffff
2372eb2:ec::/322eb2:ec:ffff:ffff:ffff:ffff:ffff:ffff
2382eb2:ed::/322eb2:ed:ffff:ffff:ffff:ffff:ffff:ffff
2392eb2:ee::/322eb2:ee:ffff:ffff:ffff:ffff:ffff:ffff
2402eb2:ef::/322eb2:ef:ffff:ffff:ffff:ffff:ffff:ffff
2412eb2:f0::/322eb2:f0:ffff:ffff:ffff:ffff:ffff:ffff
2422eb2:f1::/322eb2:f1:ffff:ffff:ffff:ffff:ffff:ffff
2432eb2:f2::/322eb2:f2:ffff:ffff:ffff:ffff:ffff:ffff
2442eb2:f3::/322eb2:f3:ffff:ffff:ffff:ffff:ffff:ffff
2452eb2:f4::/322eb2:f4:ffff:ffff:ffff:ffff:ffff:ffff
2462eb2:f5::/322eb2:f5:ffff:ffff:ffff:ffff:ffff:ffff
2472eb2:f6::/322eb2:f6:ffff:ffff:ffff:ffff:ffff:ffff
2482eb2:f7::/322eb2:f7:ffff:ffff:ffff:ffff:ffff:ffff
2492eb2:f8::/322eb2:f8:ffff:ffff:ffff:ffff:ffff:ffff
2502eb2:f9::/322eb2:f9:ffff:ffff:ffff:ffff:ffff:ffff
2512eb2:fa::/322eb2:fa:ffff:ffff:ffff:ffff:ffff:ffff
2522eb2:fb::/322eb2:fb:ffff:ffff:ffff:ffff:ffff:ffff
2532eb2:fc::/322eb2:fc:ffff:ffff:ffff:ffff:ffff:ffff
2542eb2:fd::/322eb2:fd:ffff:ffff:ffff:ffff:ffff:ffff
2552eb2:fe::/322eb2:fe:ffff:ffff:ffff:ffff:ffff:ffff
2562eb2:ff::/322eb2: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.