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

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

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