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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/119
Addresses512
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:94de:4e00/119
First address
2c19:dd:d9:dd:c25:c25:94de:4e00
Last address
2c19:dd:d9:dd:c25:c25:94de:4fff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:4e00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
e.4.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
f.4.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
/119 is not on a 4-bit boundary, so it takes 2 /120 zones.
Split into smaller subnets/127
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:d9:dd:c25:c25:94de:4e00/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:4e00/1272c19:dd:d9:dd:c25:c25:94de:4e01
22c19:dd:d9:dd:c25:c25:94de:4e02/1272c19:dd:d9:dd:c25:c25:94de:4e03
32c19:dd:d9:dd:c25:c25:94de:4e04/1272c19:dd:d9:dd:c25:c25:94de:4e05
42c19:dd:d9:dd:c25:c25:94de:4e06/1272c19:dd:d9:dd:c25:c25:94de:4e07
52c19:dd:d9:dd:c25:c25:94de:4e08/1272c19:dd:d9:dd:c25:c25:94de:4e09
62c19:dd:d9:dd:c25:c25:94de:4e0a/1272c19:dd:d9:dd:c25:c25:94de:4e0b
72c19:dd:d9:dd:c25:c25:94de:4e0c/1272c19:dd:d9:dd:c25:c25:94de:4e0d
82c19:dd:d9:dd:c25:c25:94de:4e0e/1272c19:dd:d9:dd:c25:c25:94de:4e0f
92c19:dd:d9:dd:c25:c25:94de:4e10/1272c19:dd:d9:dd:c25:c25:94de:4e11
102c19:dd:d9:dd:c25:c25:94de:4e12/1272c19:dd:d9:dd:c25:c25:94de:4e13
112c19:dd:d9:dd:c25:c25:94de:4e14/1272c19:dd:d9:dd:c25:c25:94de:4e15
122c19:dd:d9:dd:c25:c25:94de:4e16/1272c19:dd:d9:dd:c25:c25:94de:4e17
132c19:dd:d9:dd:c25:c25:94de:4e18/1272c19:dd:d9:dd:c25:c25:94de:4e19
142c19:dd:d9:dd:c25:c25:94de:4e1a/1272c19:dd:d9:dd:c25:c25:94de:4e1b
152c19:dd:d9:dd:c25:c25:94de:4e1c/1272c19:dd:d9:dd:c25:c25:94de:4e1d
162c19:dd:d9:dd:c25:c25:94de:4e1e/1272c19:dd:d9:dd:c25:c25:94de:4e1f
172c19:dd:d9:dd:c25:c25:94de:4e20/1272c19:dd:d9:dd:c25:c25:94de:4e21
182c19:dd:d9:dd:c25:c25:94de:4e22/1272c19:dd:d9:dd:c25:c25:94de:4e23
192c19:dd:d9:dd:c25:c25:94de:4e24/1272c19:dd:d9:dd:c25:c25:94de:4e25
202c19:dd:d9:dd:c25:c25:94de:4e26/1272c19:dd:d9:dd:c25:c25:94de:4e27
212c19:dd:d9:dd:c25:c25:94de:4e28/1272c19:dd:d9:dd:c25:c25:94de:4e29
222c19:dd:d9:dd:c25:c25:94de:4e2a/1272c19:dd:d9:dd:c25:c25:94de:4e2b
232c19:dd:d9:dd:c25:c25:94de:4e2c/1272c19:dd:d9:dd:c25:c25:94de:4e2d
242c19:dd:d9:dd:c25:c25:94de:4e2e/1272c19:dd:d9:dd:c25:c25:94de:4e2f
252c19:dd:d9:dd:c25:c25:94de:4e30/1272c19:dd:d9:dd:c25:c25:94de:4e31
262c19:dd:d9:dd:c25:c25:94de:4e32/1272c19:dd:d9:dd:c25:c25:94de:4e33
272c19:dd:d9:dd:c25:c25:94de:4e34/1272c19:dd:d9:dd:c25:c25:94de:4e35
282c19:dd:d9:dd:c25:c25:94de:4e36/1272c19:dd:d9:dd:c25:c25:94de:4e37
292c19:dd:d9:dd:c25:c25:94de:4e38/1272c19:dd:d9:dd:c25:c25:94de:4e39
302c19:dd:d9:dd:c25:c25:94de:4e3a/1272c19:dd:d9:dd:c25:c25:94de:4e3b
312c19:dd:d9:dd:c25:c25:94de:4e3c/1272c19:dd:d9:dd:c25:c25:94de:4e3d
322c19:dd:d9:dd:c25:c25:94de:4e3e/1272c19:dd:d9:dd:c25:c25:94de:4e3f
332c19:dd:d9:dd:c25:c25:94de:4e40/1272c19:dd:d9:dd:c25:c25:94de:4e41
342c19:dd:d9:dd:c25:c25:94de:4e42/1272c19:dd:d9:dd:c25:c25:94de:4e43
352c19:dd:d9:dd:c25:c25:94de:4e44/1272c19:dd:d9:dd:c25:c25:94de:4e45
362c19:dd:d9:dd:c25:c25:94de:4e46/1272c19:dd:d9:dd:c25:c25:94de:4e47
372c19:dd:d9:dd:c25:c25:94de:4e48/1272c19:dd:d9:dd:c25:c25:94de:4e49
382c19:dd:d9:dd:c25:c25:94de:4e4a/1272c19:dd:d9:dd:c25:c25:94de:4e4b
392c19:dd:d9:dd:c25:c25:94de:4e4c/1272c19:dd:d9:dd:c25:c25:94de:4e4d
402c19:dd:d9:dd:c25:c25:94de:4e4e/1272c19:dd:d9:dd:c25:c25:94de:4e4f
412c19:dd:d9:dd:c25:c25:94de:4e50/1272c19:dd:d9:dd:c25:c25:94de:4e51
422c19:dd:d9:dd:c25:c25:94de:4e52/1272c19:dd:d9:dd:c25:c25:94de:4e53
432c19:dd:d9:dd:c25:c25:94de:4e54/1272c19:dd:d9:dd:c25:c25:94de:4e55
442c19:dd:d9:dd:c25:c25:94de:4e56/1272c19:dd:d9:dd:c25:c25:94de:4e57
452c19:dd:d9:dd:c25:c25:94de:4e58/1272c19:dd:d9:dd:c25:c25:94de:4e59
462c19:dd:d9:dd:c25:c25:94de:4e5a/1272c19:dd:d9:dd:c25:c25:94de:4e5b
472c19:dd:d9:dd:c25:c25:94de:4e5c/1272c19:dd:d9:dd:c25:c25:94de:4e5d
482c19:dd:d9:dd:c25:c25:94de:4e5e/1272c19:dd:d9:dd:c25:c25:94de:4e5f
492c19:dd:d9:dd:c25:c25:94de:4e60/1272c19:dd:d9:dd:c25:c25:94de:4e61
502c19:dd:d9:dd:c25:c25:94de:4e62/1272c19:dd:d9:dd:c25:c25:94de:4e63
512c19:dd:d9:dd:c25:c25:94de:4e64/1272c19:dd:d9:dd:c25:c25:94de:4e65
522c19:dd:d9:dd:c25:c25:94de:4e66/1272c19:dd:d9:dd:c25:c25:94de:4e67
532c19:dd:d9:dd:c25:c25:94de:4e68/1272c19:dd:d9:dd:c25:c25:94de:4e69
542c19:dd:d9:dd:c25:c25:94de:4e6a/1272c19:dd:d9:dd:c25:c25:94de:4e6b
552c19:dd:d9:dd:c25:c25:94de:4e6c/1272c19:dd:d9:dd:c25:c25:94de:4e6d
562c19:dd:d9:dd:c25:c25:94de:4e6e/1272c19:dd:d9:dd:c25:c25:94de:4e6f
572c19:dd:d9:dd:c25:c25:94de:4e70/1272c19:dd:d9:dd:c25:c25:94de:4e71
582c19:dd:d9:dd:c25:c25:94de:4e72/1272c19:dd:d9:dd:c25:c25:94de:4e73
592c19:dd:d9:dd:c25:c25:94de:4e74/1272c19:dd:d9:dd:c25:c25:94de:4e75
602c19:dd:d9:dd:c25:c25:94de:4e76/1272c19:dd:d9:dd:c25:c25:94de:4e77
612c19:dd:d9:dd:c25:c25:94de:4e78/1272c19:dd:d9:dd:c25:c25:94de:4e79
622c19:dd:d9:dd:c25:c25:94de:4e7a/1272c19:dd:d9:dd:c25:c25:94de:4e7b
632c19:dd:d9:dd:c25:c25:94de:4e7c/1272c19:dd:d9:dd:c25:c25:94de:4e7d
642c19:dd:d9:dd:c25:c25:94de:4e7e/1272c19:dd:d9:dd:c25:c25:94de:4e7f
652c19:dd:d9:dd:c25:c25:94de:4e80/1272c19:dd:d9:dd:c25:c25:94de:4e81
662c19:dd:d9:dd:c25:c25:94de:4e82/1272c19:dd:d9:dd:c25:c25:94de:4e83
672c19:dd:d9:dd:c25:c25:94de:4e84/1272c19:dd:d9:dd:c25:c25:94de:4e85
682c19:dd:d9:dd:c25:c25:94de:4e86/1272c19:dd:d9:dd:c25:c25:94de:4e87
692c19:dd:d9:dd:c25:c25:94de:4e88/1272c19:dd:d9:dd:c25:c25:94de:4e89
702c19:dd:d9:dd:c25:c25:94de:4e8a/1272c19:dd:d9:dd:c25:c25:94de:4e8b
712c19:dd:d9:dd:c25:c25:94de:4e8c/1272c19:dd:d9:dd:c25:c25:94de:4e8d
722c19:dd:d9:dd:c25:c25:94de:4e8e/1272c19:dd:d9:dd:c25:c25:94de:4e8f
732c19:dd:d9:dd:c25:c25:94de:4e90/1272c19:dd:d9:dd:c25:c25:94de:4e91
742c19:dd:d9:dd:c25:c25:94de:4e92/1272c19:dd:d9:dd:c25:c25:94de:4e93
752c19:dd:d9:dd:c25:c25:94de:4e94/1272c19:dd:d9:dd:c25:c25:94de:4e95
762c19:dd:d9:dd:c25:c25:94de:4e96/1272c19:dd:d9:dd:c25:c25:94de:4e97
772c19:dd:d9:dd:c25:c25:94de:4e98/1272c19:dd:d9:dd:c25:c25:94de:4e99
782c19:dd:d9:dd:c25:c25:94de:4e9a/1272c19:dd:d9:dd:c25:c25:94de:4e9b
792c19:dd:d9:dd:c25:c25:94de:4e9c/1272c19:dd:d9:dd:c25:c25:94de:4e9d
802c19:dd:d9:dd:c25:c25:94de:4e9e/1272c19:dd:d9:dd:c25:c25:94de:4e9f
812c19:dd:d9:dd:c25:c25:94de:4ea0/1272c19:dd:d9:dd:c25:c25:94de:4ea1
822c19:dd:d9:dd:c25:c25:94de:4ea2/1272c19:dd:d9:dd:c25:c25:94de:4ea3
832c19:dd:d9:dd:c25:c25:94de:4ea4/1272c19:dd:d9:dd:c25:c25:94de:4ea5
842c19:dd:d9:dd:c25:c25:94de:4ea6/1272c19:dd:d9:dd:c25:c25:94de:4ea7
852c19:dd:d9:dd:c25:c25:94de:4ea8/1272c19:dd:d9:dd:c25:c25:94de:4ea9
862c19:dd:d9:dd:c25:c25:94de:4eaa/1272c19:dd:d9:dd:c25:c25:94de:4eab
872c19:dd:d9:dd:c25:c25:94de:4eac/1272c19:dd:d9:dd:c25:c25:94de:4ead
882c19:dd:d9:dd:c25:c25:94de:4eae/1272c19:dd:d9:dd:c25:c25:94de:4eaf
892c19:dd:d9:dd:c25:c25:94de:4eb0/1272c19:dd:d9:dd:c25:c25:94de:4eb1
902c19:dd:d9:dd:c25:c25:94de:4eb2/1272c19:dd:d9:dd:c25:c25:94de:4eb3
912c19:dd:d9:dd:c25:c25:94de:4eb4/1272c19:dd:d9:dd:c25:c25:94de:4eb5
922c19:dd:d9:dd:c25:c25:94de:4eb6/1272c19:dd:d9:dd:c25:c25:94de:4eb7
932c19:dd:d9:dd:c25:c25:94de:4eb8/1272c19:dd:d9:dd:c25:c25:94de:4eb9
942c19:dd:d9:dd:c25:c25:94de:4eba/1272c19:dd:d9:dd:c25:c25:94de:4ebb
952c19:dd:d9:dd:c25:c25:94de:4ebc/1272c19:dd:d9:dd:c25:c25:94de:4ebd
962c19:dd:d9:dd:c25:c25:94de:4ebe/1272c19:dd:d9:dd:c25:c25:94de:4ebf
972c19:dd:d9:dd:c25:c25:94de:4ec0/1272c19:dd:d9:dd:c25:c25:94de:4ec1
982c19:dd:d9:dd:c25:c25:94de:4ec2/1272c19:dd:d9:dd:c25:c25:94de:4ec3
992c19:dd:d9:dd:c25:c25:94de:4ec4/1272c19:dd:d9:dd:c25:c25:94de:4ec5
1002c19:dd:d9:dd:c25:c25:94de:4ec6/1272c19:dd:d9:dd:c25:c25:94de:4ec7
1012c19:dd:d9:dd:c25:c25:94de:4ec8/1272c19:dd:d9:dd:c25:c25:94de:4ec9
1022c19:dd:d9:dd:c25:c25:94de:4eca/1272c19:dd:d9:dd:c25:c25:94de:4ecb
1032c19:dd:d9:dd:c25:c25:94de:4ecc/1272c19:dd:d9:dd:c25:c25:94de:4ecd
1042c19:dd:d9:dd:c25:c25:94de:4ece/1272c19:dd:d9:dd:c25:c25:94de:4ecf
1052c19:dd:d9:dd:c25:c25:94de:4ed0/1272c19:dd:d9:dd:c25:c25:94de:4ed1
1062c19:dd:d9:dd:c25:c25:94de:4ed2/1272c19:dd:d9:dd:c25:c25:94de:4ed3
1072c19:dd:d9:dd:c25:c25:94de:4ed4/1272c19:dd:d9:dd:c25:c25:94de:4ed5
1082c19:dd:d9:dd:c25:c25:94de:4ed6/1272c19:dd:d9:dd:c25:c25:94de:4ed7
1092c19:dd:d9:dd:c25:c25:94de:4ed8/1272c19:dd:d9:dd:c25:c25:94de:4ed9
1102c19:dd:d9:dd:c25:c25:94de:4eda/1272c19:dd:d9:dd:c25:c25:94de:4edb
1112c19:dd:d9:dd:c25:c25:94de:4edc/1272c19:dd:d9:dd:c25:c25:94de:4edd
1122c19:dd:d9:dd:c25:c25:94de:4ede/1272c19:dd:d9:dd:c25:c25:94de:4edf
1132c19:dd:d9:dd:c25:c25:94de:4ee0/1272c19:dd:d9:dd:c25:c25:94de:4ee1
1142c19:dd:d9:dd:c25:c25:94de:4ee2/1272c19:dd:d9:dd:c25:c25:94de:4ee3
1152c19:dd:d9:dd:c25:c25:94de:4ee4/1272c19:dd:d9:dd:c25:c25:94de:4ee5
1162c19:dd:d9:dd:c25:c25:94de:4ee6/1272c19:dd:d9:dd:c25:c25:94de:4ee7
1172c19:dd:d9:dd:c25:c25:94de:4ee8/1272c19:dd:d9:dd:c25:c25:94de:4ee9
1182c19:dd:d9:dd:c25:c25:94de:4eea/1272c19:dd:d9:dd:c25:c25:94de:4eeb
1192c19:dd:d9:dd:c25:c25:94de:4eec/1272c19:dd:d9:dd:c25:c25:94de:4eed
1202c19:dd:d9:dd:c25:c25:94de:4eee/1272c19:dd:d9:dd:c25:c25:94de:4eef
1212c19:dd:d9:dd:c25:c25:94de:4ef0/1272c19:dd:d9:dd:c25:c25:94de:4ef1
1222c19:dd:d9:dd:c25:c25:94de:4ef2/1272c19:dd:d9:dd:c25:c25:94de:4ef3
1232c19:dd:d9:dd:c25:c25:94de:4ef4/1272c19:dd:d9:dd:c25:c25:94de:4ef5
1242c19:dd:d9:dd:c25:c25:94de:4ef6/1272c19:dd:d9:dd:c25:c25:94de:4ef7
1252c19:dd:d9:dd:c25:c25:94de:4ef8/1272c19:dd:d9:dd:c25:c25:94de:4ef9
1262c19:dd:d9:dd:c25:c25:94de:4efa/1272c19:dd:d9:dd:c25:c25:94de:4efb
1272c19:dd:d9:dd:c25:c25:94de:4efc/1272c19:dd:d9:dd:c25:c25:94de:4efd
1282c19:dd:d9:dd:c25:c25:94de:4efe/1272c19:dd:d9:dd:c25:c25:94de:4eff
1292c19:dd:d9:dd:c25:c25:94de:4f00/1272c19:dd:d9:dd:c25:c25:94de:4f01
1302c19:dd:d9:dd:c25:c25:94de:4f02/1272c19:dd:d9:dd:c25:c25:94de:4f03
1312c19:dd:d9:dd:c25:c25:94de:4f04/1272c19:dd:d9:dd:c25:c25:94de:4f05
1322c19:dd:d9:dd:c25:c25:94de:4f06/1272c19:dd:d9:dd:c25:c25:94de:4f07
1332c19:dd:d9:dd:c25:c25:94de:4f08/1272c19:dd:d9:dd:c25:c25:94de:4f09
1342c19:dd:d9:dd:c25:c25:94de:4f0a/1272c19:dd:d9:dd:c25:c25:94de:4f0b
1352c19:dd:d9:dd:c25:c25:94de:4f0c/1272c19:dd:d9:dd:c25:c25:94de:4f0d
1362c19:dd:d9:dd:c25:c25:94de:4f0e/1272c19:dd:d9:dd:c25:c25:94de:4f0f
1372c19:dd:d9:dd:c25:c25:94de:4f10/1272c19:dd:d9:dd:c25:c25:94de:4f11
1382c19:dd:d9:dd:c25:c25:94de:4f12/1272c19:dd:d9:dd:c25:c25:94de:4f13
1392c19:dd:d9:dd:c25:c25:94de:4f14/1272c19:dd:d9:dd:c25:c25:94de:4f15
1402c19:dd:d9:dd:c25:c25:94de:4f16/1272c19:dd:d9:dd:c25:c25:94de:4f17
1412c19:dd:d9:dd:c25:c25:94de:4f18/1272c19:dd:d9:dd:c25:c25:94de:4f19
1422c19:dd:d9:dd:c25:c25:94de:4f1a/1272c19:dd:d9:dd:c25:c25:94de:4f1b
1432c19:dd:d9:dd:c25:c25:94de:4f1c/1272c19:dd:d9:dd:c25:c25:94de:4f1d
1442c19:dd:d9:dd:c25:c25:94de:4f1e/1272c19:dd:d9:dd:c25:c25:94de:4f1f
1452c19:dd:d9:dd:c25:c25:94de:4f20/1272c19:dd:d9:dd:c25:c25:94de:4f21
1462c19:dd:d9:dd:c25:c25:94de:4f22/1272c19:dd:d9:dd:c25:c25:94de:4f23
1472c19:dd:d9:dd:c25:c25:94de:4f24/1272c19:dd:d9:dd:c25:c25:94de:4f25
1482c19:dd:d9:dd:c25:c25:94de:4f26/1272c19:dd:d9:dd:c25:c25:94de:4f27
1492c19:dd:d9:dd:c25:c25:94de:4f28/1272c19:dd:d9:dd:c25:c25:94de:4f29
1502c19:dd:d9:dd:c25:c25:94de:4f2a/1272c19:dd:d9:dd:c25:c25:94de:4f2b
1512c19:dd:d9:dd:c25:c25:94de:4f2c/1272c19:dd:d9:dd:c25:c25:94de:4f2d
1522c19:dd:d9:dd:c25:c25:94de:4f2e/1272c19:dd:d9:dd:c25:c25:94de:4f2f
1532c19:dd:d9:dd:c25:c25:94de:4f30/1272c19:dd:d9:dd:c25:c25:94de:4f31
1542c19:dd:d9:dd:c25:c25:94de:4f32/1272c19:dd:d9:dd:c25:c25:94de:4f33
1552c19:dd:d9:dd:c25:c25:94de:4f34/1272c19:dd:d9:dd:c25:c25:94de:4f35
1562c19:dd:d9:dd:c25:c25:94de:4f36/1272c19:dd:d9:dd:c25:c25:94de:4f37
1572c19:dd:d9:dd:c25:c25:94de:4f38/1272c19:dd:d9:dd:c25:c25:94de:4f39
1582c19:dd:d9:dd:c25:c25:94de:4f3a/1272c19:dd:d9:dd:c25:c25:94de:4f3b
1592c19:dd:d9:dd:c25:c25:94de:4f3c/1272c19:dd:d9:dd:c25:c25:94de:4f3d
1602c19:dd:d9:dd:c25:c25:94de:4f3e/1272c19:dd:d9:dd:c25:c25:94de:4f3f
1612c19:dd:d9:dd:c25:c25:94de:4f40/1272c19:dd:d9:dd:c25:c25:94de:4f41
1622c19:dd:d9:dd:c25:c25:94de:4f42/1272c19:dd:d9:dd:c25:c25:94de:4f43
1632c19:dd:d9:dd:c25:c25:94de:4f44/1272c19:dd:d9:dd:c25:c25:94de:4f45
1642c19:dd:d9:dd:c25:c25:94de:4f46/1272c19:dd:d9:dd:c25:c25:94de:4f47
1652c19:dd:d9:dd:c25:c25:94de:4f48/1272c19:dd:d9:dd:c25:c25:94de:4f49
1662c19:dd:d9:dd:c25:c25:94de:4f4a/1272c19:dd:d9:dd:c25:c25:94de:4f4b
1672c19:dd:d9:dd:c25:c25:94de:4f4c/1272c19:dd:d9:dd:c25:c25:94de:4f4d
1682c19:dd:d9:dd:c25:c25:94de:4f4e/1272c19:dd:d9:dd:c25:c25:94de:4f4f
1692c19:dd:d9:dd:c25:c25:94de:4f50/1272c19:dd:d9:dd:c25:c25:94de:4f51
1702c19:dd:d9:dd:c25:c25:94de:4f52/1272c19:dd:d9:dd:c25:c25:94de:4f53
1712c19:dd:d9:dd:c25:c25:94de:4f54/1272c19:dd:d9:dd:c25:c25:94de:4f55
1722c19:dd:d9:dd:c25:c25:94de:4f56/1272c19:dd:d9:dd:c25:c25:94de:4f57
1732c19:dd:d9:dd:c25:c25:94de:4f58/1272c19:dd:d9:dd:c25:c25:94de:4f59
1742c19:dd:d9:dd:c25:c25:94de:4f5a/1272c19:dd:d9:dd:c25:c25:94de:4f5b
1752c19:dd:d9:dd:c25:c25:94de:4f5c/1272c19:dd:d9:dd:c25:c25:94de:4f5d
1762c19:dd:d9:dd:c25:c25:94de:4f5e/1272c19:dd:d9:dd:c25:c25:94de:4f5f
1772c19:dd:d9:dd:c25:c25:94de:4f60/1272c19:dd:d9:dd:c25:c25:94de:4f61
1782c19:dd:d9:dd:c25:c25:94de:4f62/1272c19:dd:d9:dd:c25:c25:94de:4f63
1792c19:dd:d9:dd:c25:c25:94de:4f64/1272c19:dd:d9:dd:c25:c25:94de:4f65
1802c19:dd:d9:dd:c25:c25:94de:4f66/1272c19:dd:d9:dd:c25:c25:94de:4f67
1812c19:dd:d9:dd:c25:c25:94de:4f68/1272c19:dd:d9:dd:c25:c25:94de:4f69
1822c19:dd:d9:dd:c25:c25:94de:4f6a/1272c19:dd:d9:dd:c25:c25:94de:4f6b
1832c19:dd:d9:dd:c25:c25:94de:4f6c/1272c19:dd:d9:dd:c25:c25:94de:4f6d
1842c19:dd:d9:dd:c25:c25:94de:4f6e/1272c19:dd:d9:dd:c25:c25:94de:4f6f
1852c19:dd:d9:dd:c25:c25:94de:4f70/1272c19:dd:d9:dd:c25:c25:94de:4f71
1862c19:dd:d9:dd:c25:c25:94de:4f72/1272c19:dd:d9:dd:c25:c25:94de:4f73
1872c19:dd:d9:dd:c25:c25:94de:4f74/1272c19:dd:d9:dd:c25:c25:94de:4f75
1882c19:dd:d9:dd:c25:c25:94de:4f76/1272c19:dd:d9:dd:c25:c25:94de:4f77
1892c19:dd:d9:dd:c25:c25:94de:4f78/1272c19:dd:d9:dd:c25:c25:94de:4f79
1902c19:dd:d9:dd:c25:c25:94de:4f7a/1272c19:dd:d9:dd:c25:c25:94de:4f7b
1912c19:dd:d9:dd:c25:c25:94de:4f7c/1272c19:dd:d9:dd:c25:c25:94de:4f7d
1922c19:dd:d9:dd:c25:c25:94de:4f7e/1272c19:dd:d9:dd:c25:c25:94de:4f7f
1932c19:dd:d9:dd:c25:c25:94de:4f80/1272c19:dd:d9:dd:c25:c25:94de:4f81
1942c19:dd:d9:dd:c25:c25:94de:4f82/1272c19:dd:d9:dd:c25:c25:94de:4f83
1952c19:dd:d9:dd:c25:c25:94de:4f84/1272c19:dd:d9:dd:c25:c25:94de:4f85
1962c19:dd:d9:dd:c25:c25:94de:4f86/1272c19:dd:d9:dd:c25:c25:94de:4f87
1972c19:dd:d9:dd:c25:c25:94de:4f88/1272c19:dd:d9:dd:c25:c25:94de:4f89
1982c19:dd:d9:dd:c25:c25:94de:4f8a/1272c19:dd:d9:dd:c25:c25:94de:4f8b
1992c19:dd:d9:dd:c25:c25:94de:4f8c/1272c19:dd:d9:dd:c25:c25:94de:4f8d
2002c19:dd:d9:dd:c25:c25:94de:4f8e/1272c19:dd:d9:dd:c25:c25:94de:4f8f
2012c19:dd:d9:dd:c25:c25:94de:4f90/1272c19:dd:d9:dd:c25:c25:94de:4f91
2022c19:dd:d9:dd:c25:c25:94de:4f92/1272c19:dd:d9:dd:c25:c25:94de:4f93
2032c19:dd:d9:dd:c25:c25:94de:4f94/1272c19:dd:d9:dd:c25:c25:94de:4f95
2042c19:dd:d9:dd:c25:c25:94de:4f96/1272c19:dd:d9:dd:c25:c25:94de:4f97
2052c19:dd:d9:dd:c25:c25:94de:4f98/1272c19:dd:d9:dd:c25:c25:94de:4f99
2062c19:dd:d9:dd:c25:c25:94de:4f9a/1272c19:dd:d9:dd:c25:c25:94de:4f9b
2072c19:dd:d9:dd:c25:c25:94de:4f9c/1272c19:dd:d9:dd:c25:c25:94de:4f9d
2082c19:dd:d9:dd:c25:c25:94de:4f9e/1272c19:dd:d9:dd:c25:c25:94de:4f9f
2092c19:dd:d9:dd:c25:c25:94de:4fa0/1272c19:dd:d9:dd:c25:c25:94de:4fa1
2102c19:dd:d9:dd:c25:c25:94de:4fa2/1272c19:dd:d9:dd:c25:c25:94de:4fa3
2112c19:dd:d9:dd:c25:c25:94de:4fa4/1272c19:dd:d9:dd:c25:c25:94de:4fa5
2122c19:dd:d9:dd:c25:c25:94de:4fa6/1272c19:dd:d9:dd:c25:c25:94de:4fa7
2132c19:dd:d9:dd:c25:c25:94de:4fa8/1272c19:dd:d9:dd:c25:c25:94de:4fa9
2142c19:dd:d9:dd:c25:c25:94de:4faa/1272c19:dd:d9:dd:c25:c25:94de:4fab
2152c19:dd:d9:dd:c25:c25:94de:4fac/1272c19:dd:d9:dd:c25:c25:94de:4fad
2162c19:dd:d9:dd:c25:c25:94de:4fae/1272c19:dd:d9:dd:c25:c25:94de:4faf
2172c19:dd:d9:dd:c25:c25:94de:4fb0/1272c19:dd:d9:dd:c25:c25:94de:4fb1
2182c19:dd:d9:dd:c25:c25:94de:4fb2/1272c19:dd:d9:dd:c25:c25:94de:4fb3
2192c19:dd:d9:dd:c25:c25:94de:4fb4/1272c19:dd:d9:dd:c25:c25:94de:4fb5
2202c19:dd:d9:dd:c25:c25:94de:4fb6/1272c19:dd:d9:dd:c25:c25:94de:4fb7
2212c19:dd:d9:dd:c25:c25:94de:4fb8/1272c19:dd:d9:dd:c25:c25:94de:4fb9
2222c19:dd:d9:dd:c25:c25:94de:4fba/1272c19:dd:d9:dd:c25:c25:94de:4fbb
2232c19:dd:d9:dd:c25:c25:94de:4fbc/1272c19:dd:d9:dd:c25:c25:94de:4fbd
2242c19:dd:d9:dd:c25:c25:94de:4fbe/1272c19:dd:d9:dd:c25:c25:94de:4fbf
2252c19:dd:d9:dd:c25:c25:94de:4fc0/1272c19:dd:d9:dd:c25:c25:94de:4fc1
2262c19:dd:d9:dd:c25:c25:94de:4fc2/1272c19:dd:d9:dd:c25:c25:94de:4fc3
2272c19:dd:d9:dd:c25:c25:94de:4fc4/1272c19:dd:d9:dd:c25:c25:94de:4fc5
2282c19:dd:d9:dd:c25:c25:94de:4fc6/1272c19:dd:d9:dd:c25:c25:94de:4fc7
2292c19:dd:d9:dd:c25:c25:94de:4fc8/1272c19:dd:d9:dd:c25:c25:94de:4fc9
2302c19:dd:d9:dd:c25:c25:94de:4fca/1272c19:dd:d9:dd:c25:c25:94de:4fcb
2312c19:dd:d9:dd:c25:c25:94de:4fcc/1272c19:dd:d9:dd:c25:c25:94de:4fcd
2322c19:dd:d9:dd:c25:c25:94de:4fce/1272c19:dd:d9:dd:c25:c25:94de:4fcf
2332c19:dd:d9:dd:c25:c25:94de:4fd0/1272c19:dd:d9:dd:c25:c25:94de:4fd1
2342c19:dd:d9:dd:c25:c25:94de:4fd2/1272c19:dd:d9:dd:c25:c25:94de:4fd3
2352c19:dd:d9:dd:c25:c25:94de:4fd4/1272c19:dd:d9:dd:c25:c25:94de:4fd5
2362c19:dd:d9:dd:c25:c25:94de:4fd6/1272c19:dd:d9:dd:c25:c25:94de:4fd7
2372c19:dd:d9:dd:c25:c25:94de:4fd8/1272c19:dd:d9:dd:c25:c25:94de:4fd9
2382c19:dd:d9:dd:c25:c25:94de:4fda/1272c19:dd:d9:dd:c25:c25:94de:4fdb
2392c19:dd:d9:dd:c25:c25:94de:4fdc/1272c19:dd:d9:dd:c25:c25:94de:4fdd
2402c19:dd:d9:dd:c25:c25:94de:4fde/1272c19:dd:d9:dd:c25:c25:94de:4fdf
2412c19:dd:d9:dd:c25:c25:94de:4fe0/1272c19:dd:d9:dd:c25:c25:94de:4fe1
2422c19:dd:d9:dd:c25:c25:94de:4fe2/1272c19:dd:d9:dd:c25:c25:94de:4fe3
2432c19:dd:d9:dd:c25:c25:94de:4fe4/1272c19:dd:d9:dd:c25:c25:94de:4fe5
2442c19:dd:d9:dd:c25:c25:94de:4fe6/1272c19:dd:d9:dd:c25:c25:94de:4fe7
2452c19:dd:d9:dd:c25:c25:94de:4fe8/1272c19:dd:d9:dd:c25:c25:94de:4fe9
2462c19:dd:d9:dd:c25:c25:94de:4fea/1272c19:dd:d9:dd:c25:c25:94de:4feb
2472c19:dd:d9:dd:c25:c25:94de:4fec/1272c19:dd:d9:dd:c25:c25:94de:4fed
2482c19:dd:d9:dd:c25:c25:94de:4fee/1272c19:dd:d9:dd:c25:c25:94de:4fef
2492c19:dd:d9:dd:c25:c25:94de:4ff0/1272c19:dd:d9:dd:c25:c25:94de:4ff1
2502c19:dd:d9:dd:c25:c25:94de:4ff2/1272c19:dd:d9:dd:c25:c25:94de:4ff3
2512c19:dd:d9:dd:c25:c25:94de:4ff4/1272c19:dd:d9:dd:c25:c25:94de:4ff5
2522c19:dd:d9:dd:c25:c25:94de:4ff6/1272c19:dd:d9:dd:c25:c25:94de:4ff7
2532c19:dd:d9:dd:c25:c25:94de:4ff8/1272c19:dd:d9:dd:c25:c25:94de:4ff9
2542c19:dd:d9:dd:c25:c25:94de:4ffa/1272c19:dd:d9:dd:c25:c25:94de:4ffb
2552c19:dd:d9:dd:c25:c25:94de:4ffc/1272c19:dd:d9:dd:c25:c25:94de:4ffd
2562c19:dd:d9:dd:c25:c25:94de:4ffe/1272c19:dd:d9:dd:c25:c25:94de:4fff

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.