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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/7
Addresses2^121
/64 networks2^57
Network
2e00::/7
First address
2e00::
Last address
2fff:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
2,658,455,991,569,831,745,807,614,120,560,689,152 (2^121)
/64 networks (LANs)
144,115,188,075,855,872 (2^57)
Full form
2e00:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
e.2.ip6.arpa
f.2.ip6.arpa
/7 is not on a 4-bit boundary, so it takes 2 /8 zones.
Split into smaller subnets/16
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/16 (512)/20 (8,192)

2e00::/7 makes 512 subnets of /16; the first 256 are listed.

Subnets
#SubnetLast address
12e00::/162e00:ffff:ffff:ffff:ffff:ffff:ffff:ffff
22e01::/162e01:ffff:ffff:ffff:ffff:ffff:ffff:ffff
32e02::/162e02:ffff:ffff:ffff:ffff:ffff:ffff:ffff
42e03::/162e03:ffff:ffff:ffff:ffff:ffff:ffff:ffff
52e04::/162e04:ffff:ffff:ffff:ffff:ffff:ffff:ffff
62e05::/162e05:ffff:ffff:ffff:ffff:ffff:ffff:ffff
72e06::/162e06:ffff:ffff:ffff:ffff:ffff:ffff:ffff
82e07::/162e07:ffff:ffff:ffff:ffff:ffff:ffff:ffff
92e08::/162e08:ffff:ffff:ffff:ffff:ffff:ffff:ffff
102e09::/162e09:ffff:ffff:ffff:ffff:ffff:ffff:ffff
112e0a::/162e0a:ffff:ffff:ffff:ffff:ffff:ffff:ffff
122e0b::/162e0b:ffff:ffff:ffff:ffff:ffff:ffff:ffff
132e0c::/162e0c:ffff:ffff:ffff:ffff:ffff:ffff:ffff
142e0d::/162e0d:ffff:ffff:ffff:ffff:ffff:ffff:ffff
152e0e::/162e0e:ffff:ffff:ffff:ffff:ffff:ffff:ffff
162e0f::/162e0f:ffff:ffff:ffff:ffff:ffff:ffff:ffff
172e10::/162e10:ffff:ffff:ffff:ffff:ffff:ffff:ffff
182e11::/162e11:ffff:ffff:ffff:ffff:ffff:ffff:ffff
192e12::/162e12:ffff:ffff:ffff:ffff:ffff:ffff:ffff
202e13::/162e13:ffff:ffff:ffff:ffff:ffff:ffff:ffff
212e14::/162e14:ffff:ffff:ffff:ffff:ffff:ffff:ffff
222e15::/162e15:ffff:ffff:ffff:ffff:ffff:ffff:ffff
232e16::/162e16:ffff:ffff:ffff:ffff:ffff:ffff:ffff
242e17::/162e17:ffff:ffff:ffff:ffff:ffff:ffff:ffff
252e18::/162e18:ffff:ffff:ffff:ffff:ffff:ffff:ffff
262e19::/162e19:ffff:ffff:ffff:ffff:ffff:ffff:ffff
272e1a::/162e1a:ffff:ffff:ffff:ffff:ffff:ffff:ffff
282e1b::/162e1b:ffff:ffff:ffff:ffff:ffff:ffff:ffff
292e1c::/162e1c:ffff:ffff:ffff:ffff:ffff:ffff:ffff
302e1d::/162e1d:ffff:ffff:ffff:ffff:ffff:ffff:ffff
312e1e::/162e1e:ffff:ffff:ffff:ffff:ffff:ffff:ffff
322e1f::/162e1f:ffff:ffff:ffff:ffff:ffff:ffff:ffff
332e20::/162e20:ffff:ffff:ffff:ffff:ffff:ffff:ffff
342e21::/162e21:ffff:ffff:ffff:ffff:ffff:ffff:ffff
352e22::/162e22:ffff:ffff:ffff:ffff:ffff:ffff:ffff
362e23::/162e23:ffff:ffff:ffff:ffff:ffff:ffff:ffff
372e24::/162e24:ffff:ffff:ffff:ffff:ffff:ffff:ffff
382e25::/162e25:ffff:ffff:ffff:ffff:ffff:ffff:ffff
392e26::/162e26:ffff:ffff:ffff:ffff:ffff:ffff:ffff
402e27::/162e27:ffff:ffff:ffff:ffff:ffff:ffff:ffff
412e28::/162e28:ffff:ffff:ffff:ffff:ffff:ffff:ffff
422e29::/162e29:ffff:ffff:ffff:ffff:ffff:ffff:ffff
432e2a::/162e2a:ffff:ffff:ffff:ffff:ffff:ffff:ffff
442e2b::/162e2b:ffff:ffff:ffff:ffff:ffff:ffff:ffff
452e2c::/162e2c:ffff:ffff:ffff:ffff:ffff:ffff:ffff
462e2d::/162e2d:ffff:ffff:ffff:ffff:ffff:ffff:ffff
472e2e::/162e2e:ffff:ffff:ffff:ffff:ffff:ffff:ffff
482e2f::/162e2f:ffff:ffff:ffff:ffff:ffff:ffff:ffff
492e30::/162e30:ffff:ffff:ffff:ffff:ffff:ffff:ffff
502e31::/162e31:ffff:ffff:ffff:ffff:ffff:ffff:ffff
512e32::/162e32:ffff:ffff:ffff:ffff:ffff:ffff:ffff
522e33::/162e33:ffff:ffff:ffff:ffff:ffff:ffff:ffff
532e34::/162e34:ffff:ffff:ffff:ffff:ffff:ffff:ffff
542e35::/162e35:ffff:ffff:ffff:ffff:ffff:ffff:ffff
552e36::/162e36:ffff:ffff:ffff:ffff:ffff:ffff:ffff
562e37::/162e37:ffff:ffff:ffff:ffff:ffff:ffff:ffff
572e38::/162e38:ffff:ffff:ffff:ffff:ffff:ffff:ffff
582e39::/162e39:ffff:ffff:ffff:ffff:ffff:ffff:ffff
592e3a::/162e3a:ffff:ffff:ffff:ffff:ffff:ffff:ffff
602e3b::/162e3b:ffff:ffff:ffff:ffff:ffff:ffff:ffff
612e3c::/162e3c:ffff:ffff:ffff:ffff:ffff:ffff:ffff
622e3d::/162e3d:ffff:ffff:ffff:ffff:ffff:ffff:ffff
632e3e::/162e3e:ffff:ffff:ffff:ffff:ffff:ffff:ffff
642e3f::/162e3f:ffff:ffff:ffff:ffff:ffff:ffff:ffff
652e40::/162e40:ffff:ffff:ffff:ffff:ffff:ffff:ffff
662e41::/162e41:ffff:ffff:ffff:ffff:ffff:ffff:ffff
672e42::/162e42:ffff:ffff:ffff:ffff:ffff:ffff:ffff
682e43::/162e43:ffff:ffff:ffff:ffff:ffff:ffff:ffff
692e44::/162e44:ffff:ffff:ffff:ffff:ffff:ffff:ffff
702e45::/162e45:ffff:ffff:ffff:ffff:ffff:ffff:ffff
712e46::/162e46:ffff:ffff:ffff:ffff:ffff:ffff:ffff
722e47::/162e47:ffff:ffff:ffff:ffff:ffff:ffff:ffff
732e48::/162e48:ffff:ffff:ffff:ffff:ffff:ffff:ffff
742e49::/162e49:ffff:ffff:ffff:ffff:ffff:ffff:ffff
752e4a::/162e4a:ffff:ffff:ffff:ffff:ffff:ffff:ffff
762e4b::/162e4b:ffff:ffff:ffff:ffff:ffff:ffff:ffff
772e4c::/162e4c:ffff:ffff:ffff:ffff:ffff:ffff:ffff
782e4d::/162e4d:ffff:ffff:ffff:ffff:ffff:ffff:ffff
792e4e::/162e4e:ffff:ffff:ffff:ffff:ffff:ffff:ffff
802e4f::/162e4f:ffff:ffff:ffff:ffff:ffff:ffff:ffff
812e50::/162e50:ffff:ffff:ffff:ffff:ffff:ffff:ffff
822e51::/162e51:ffff:ffff:ffff:ffff:ffff:ffff:ffff
832e52::/162e52:ffff:ffff:ffff:ffff:ffff:ffff:ffff
842e53::/162e53:ffff:ffff:ffff:ffff:ffff:ffff:ffff
852e54::/162e54:ffff:ffff:ffff:ffff:ffff:ffff:ffff
862e55::/162e55:ffff:ffff:ffff:ffff:ffff:ffff:ffff
872e56::/162e56:ffff:ffff:ffff:ffff:ffff:ffff:ffff
882e57::/162e57:ffff:ffff:ffff:ffff:ffff:ffff:ffff
892e58::/162e58:ffff:ffff:ffff:ffff:ffff:ffff:ffff
902e59::/162e59:ffff:ffff:ffff:ffff:ffff:ffff:ffff
912e5a::/162e5a:ffff:ffff:ffff:ffff:ffff:ffff:ffff
922e5b::/162e5b:ffff:ffff:ffff:ffff:ffff:ffff:ffff
932e5c::/162e5c:ffff:ffff:ffff:ffff:ffff:ffff:ffff
942e5d::/162e5d:ffff:ffff:ffff:ffff:ffff:ffff:ffff
952e5e::/162e5e:ffff:ffff:ffff:ffff:ffff:ffff:ffff
962e5f::/162e5f:ffff:ffff:ffff:ffff:ffff:ffff:ffff
972e60::/162e60:ffff:ffff:ffff:ffff:ffff:ffff:ffff
982e61::/162e61:ffff:ffff:ffff:ffff:ffff:ffff:ffff
992e62::/162e62:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1002e63::/162e63:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1012e64::/162e64:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1022e65::/162e65:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1032e66::/162e66:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1042e67::/162e67:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1052e68::/162e68:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1062e69::/162e69:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1072e6a::/162e6a:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1082e6b::/162e6b:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1092e6c::/162e6c:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1102e6d::/162e6d:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1112e6e::/162e6e:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1122e6f::/162e6f:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1132e70::/162e70:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1142e71::/162e71:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1152e72::/162e72:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1162e73::/162e73:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1172e74::/162e74:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1182e75::/162e75:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1192e76::/162e76:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1202e77::/162e77:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1212e78::/162e78:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1222e79::/162e79:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1232e7a::/162e7a:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1242e7b::/162e7b:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1252e7c::/162e7c:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1262e7d::/162e7d:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1272e7e::/162e7e:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1282e7f::/162e7f:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1292e80::/162e80:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1302e81::/162e81:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1312e82::/162e82:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1322e83::/162e83:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1332e84::/162e84:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1342e85::/162e85:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1352e86::/162e86:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1362e87::/162e87:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1372e88::/162e88:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1382e89::/162e89:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1392e8a::/162e8a:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1402e8b::/162e8b:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1412e8c::/162e8c:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1422e8d::/162e8d:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1432e8e::/162e8e:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1442e8f::/162e8f:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1452e90::/162e90:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1462e91::/162e91:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1472e92::/162e92:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1482e93::/162e93:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1492e94::/162e94:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1502e95::/162e95:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1512e96::/162e96:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1522e97::/162e97:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1532e98::/162e98:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1542e99::/162e99:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1552e9a::/162e9a:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1562e9b::/162e9b:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1572e9c::/162e9c:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1582e9d::/162e9d:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1592e9e::/162e9e:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1602e9f::/162e9f:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1612ea0::/162ea0:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1622ea1::/162ea1:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1632ea2::/162ea2:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1642ea3::/162ea3:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1652ea4::/162ea4:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1662ea5::/162ea5:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1672ea6::/162ea6:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1682ea7::/162ea7:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1692ea8::/162ea8:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1702ea9::/162ea9:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1712eaa::/162eaa:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1722eab::/162eab:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1732eac::/162eac:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1742ead::/162ead:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1752eae::/162eae:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1762eaf::/162eaf:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1772eb0::/162eb0:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1782eb1::/162eb1:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1792eb2::/162eb2:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1802eb3::/162eb3:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1812eb4::/162eb4:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1822eb5::/162eb5:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1832eb6::/162eb6:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1842eb7::/162eb7:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1852eb8::/162eb8:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1862eb9::/162eb9:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1872eba::/162eba:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1882ebb::/162ebb:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1892ebc::/162ebc:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1902ebd::/162ebd:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1912ebe::/162ebe:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1922ebf::/162ebf:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1932ec0::/162ec0:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1942ec1::/162ec1:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1952ec2::/162ec2:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1962ec3::/162ec3:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1972ec4::/162ec4:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1982ec5::/162ec5:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1992ec6::/162ec6:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2002ec7::/162ec7:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2012ec8::/162ec8:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2022ec9::/162ec9:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2032eca::/162eca:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2042ecb::/162ecb:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2052ecc::/162ecc:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2062ecd::/162ecd:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2072ece::/162ece:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2082ecf::/162ecf:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2092ed0::/162ed0:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2102ed1::/162ed1:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2112ed2::/162ed2:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2122ed3::/162ed3:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2132ed4::/162ed4:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2142ed5::/162ed5:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2152ed6::/162ed6:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2162ed7::/162ed7:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2172ed8::/162ed8:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2182ed9::/162ed9:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2192eda::/162eda:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2202edb::/162edb:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2212edc::/162edc:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2222edd::/162edd:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2232ede::/162ede:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2242edf::/162edf:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2252ee0::/162ee0:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2262ee1::/162ee1:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2272ee2::/162ee2:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2282ee3::/162ee3:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2292ee4::/162ee4:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2302ee5::/162ee5:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2312ee6::/162ee6:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2322ee7::/162ee7:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2332ee8::/162ee8:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2342ee9::/162ee9:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2352eea::/162eea:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2362eeb::/162eeb:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2372eec::/162eec:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2382eed::/162eed:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2392eee::/162eee:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2402eef::/162eef:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2412ef0::/162ef0:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2422ef1::/162ef1:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2432ef2::/162ef2:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2442ef3::/162ef3:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2452ef4::/162ef4:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2462ef5::/162ef5:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2472ef6::/162ef6:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2482ef7::/162ef7:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2492ef8::/162ef8:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2502ef9::/162ef9:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2512efa::/162efa:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2522efb::/162efb:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2532efc::/162efc:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2542efd::/162efd:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2552efe::/162efe:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2562eff::/162eff:ffff: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.