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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/120
Addresses256
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:94de:2f00/120
First address
2c19:dd:d9:dd:c25:c25:94de:2f00
Last address
2c19:dd:d9:dd:c25:c25:94de:2fff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:2f00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
f.2.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
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25:94de:2f00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:2f00/1282c19:dd:d9:dd:c25:c25:94de:2f00
22c19:dd:d9:dd:c25:c25:94de:2f01/1282c19:dd:d9:dd:c25:c25:94de:2f01
32c19:dd:d9:dd:c25:c25:94de:2f02/1282c19:dd:d9:dd:c25:c25:94de:2f02
42c19:dd:d9:dd:c25:c25:94de:2f03/1282c19:dd:d9:dd:c25:c25:94de:2f03
52c19:dd:d9:dd:c25:c25:94de:2f04/1282c19:dd:d9:dd:c25:c25:94de:2f04
62c19:dd:d9:dd:c25:c25:94de:2f05/1282c19:dd:d9:dd:c25:c25:94de:2f05
72c19:dd:d9:dd:c25:c25:94de:2f06/1282c19:dd:d9:dd:c25:c25:94de:2f06
82c19:dd:d9:dd:c25:c25:94de:2f07/1282c19:dd:d9:dd:c25:c25:94de:2f07
92c19:dd:d9:dd:c25:c25:94de:2f08/1282c19:dd:d9:dd:c25:c25:94de:2f08
102c19:dd:d9:dd:c25:c25:94de:2f09/1282c19:dd:d9:dd:c25:c25:94de:2f09
112c19:dd:d9:dd:c25:c25:94de:2f0a/1282c19:dd:d9:dd:c25:c25:94de:2f0a
122c19:dd:d9:dd:c25:c25:94de:2f0b/1282c19:dd:d9:dd:c25:c25:94de:2f0b
132c19:dd:d9:dd:c25:c25:94de:2f0c/1282c19:dd:d9:dd:c25:c25:94de:2f0c
142c19:dd:d9:dd:c25:c25:94de:2f0d/1282c19:dd:d9:dd:c25:c25:94de:2f0d
152c19:dd:d9:dd:c25:c25:94de:2f0e/1282c19:dd:d9:dd:c25:c25:94de:2f0e
162c19:dd:d9:dd:c25:c25:94de:2f0f/1282c19:dd:d9:dd:c25:c25:94de:2f0f
172c19:dd:d9:dd:c25:c25:94de:2f10/1282c19:dd:d9:dd:c25:c25:94de:2f10
182c19:dd:d9:dd:c25:c25:94de:2f11/1282c19:dd:d9:dd:c25:c25:94de:2f11
192c19:dd:d9:dd:c25:c25:94de:2f12/1282c19:dd:d9:dd:c25:c25:94de:2f12
202c19:dd:d9:dd:c25:c25:94de:2f13/1282c19:dd:d9:dd:c25:c25:94de:2f13
212c19:dd:d9:dd:c25:c25:94de:2f14/1282c19:dd:d9:dd:c25:c25:94de:2f14
222c19:dd:d9:dd:c25:c25:94de:2f15/1282c19:dd:d9:dd:c25:c25:94de:2f15
232c19:dd:d9:dd:c25:c25:94de:2f16/1282c19:dd:d9:dd:c25:c25:94de:2f16
242c19:dd:d9:dd:c25:c25:94de:2f17/1282c19:dd:d9:dd:c25:c25:94de:2f17
252c19:dd:d9:dd:c25:c25:94de:2f18/1282c19:dd:d9:dd:c25:c25:94de:2f18
262c19:dd:d9:dd:c25:c25:94de:2f19/1282c19:dd:d9:dd:c25:c25:94de:2f19
272c19:dd:d9:dd:c25:c25:94de:2f1a/1282c19:dd:d9:dd:c25:c25:94de:2f1a
282c19:dd:d9:dd:c25:c25:94de:2f1b/1282c19:dd:d9:dd:c25:c25:94de:2f1b
292c19:dd:d9:dd:c25:c25:94de:2f1c/1282c19:dd:d9:dd:c25:c25:94de:2f1c
302c19:dd:d9:dd:c25:c25:94de:2f1d/1282c19:dd:d9:dd:c25:c25:94de:2f1d
312c19:dd:d9:dd:c25:c25:94de:2f1e/1282c19:dd:d9:dd:c25:c25:94de:2f1e
322c19:dd:d9:dd:c25:c25:94de:2f1f/1282c19:dd:d9:dd:c25:c25:94de:2f1f
332c19:dd:d9:dd:c25:c25:94de:2f20/1282c19:dd:d9:dd:c25:c25:94de:2f20
342c19:dd:d9:dd:c25:c25:94de:2f21/1282c19:dd:d9:dd:c25:c25:94de:2f21
352c19:dd:d9:dd:c25:c25:94de:2f22/1282c19:dd:d9:dd:c25:c25:94de:2f22
362c19:dd:d9:dd:c25:c25:94de:2f23/1282c19:dd:d9:dd:c25:c25:94de:2f23
372c19:dd:d9:dd:c25:c25:94de:2f24/1282c19:dd:d9:dd:c25:c25:94de:2f24
382c19:dd:d9:dd:c25:c25:94de:2f25/1282c19:dd:d9:dd:c25:c25:94de:2f25
392c19:dd:d9:dd:c25:c25:94de:2f26/1282c19:dd:d9:dd:c25:c25:94de:2f26
402c19:dd:d9:dd:c25:c25:94de:2f27/1282c19:dd:d9:dd:c25:c25:94de:2f27
412c19:dd:d9:dd:c25:c25:94de:2f28/1282c19:dd:d9:dd:c25:c25:94de:2f28
422c19:dd:d9:dd:c25:c25:94de:2f29/1282c19:dd:d9:dd:c25:c25:94de:2f29
432c19:dd:d9:dd:c25:c25:94de:2f2a/1282c19:dd:d9:dd:c25:c25:94de:2f2a
442c19:dd:d9:dd:c25:c25:94de:2f2b/1282c19:dd:d9:dd:c25:c25:94de:2f2b
452c19:dd:d9:dd:c25:c25:94de:2f2c/1282c19:dd:d9:dd:c25:c25:94de:2f2c
462c19:dd:d9:dd:c25:c25:94de:2f2d/1282c19:dd:d9:dd:c25:c25:94de:2f2d
472c19:dd:d9:dd:c25:c25:94de:2f2e/1282c19:dd:d9:dd:c25:c25:94de:2f2e
482c19:dd:d9:dd:c25:c25:94de:2f2f/1282c19:dd:d9:dd:c25:c25:94de:2f2f
492c19:dd:d9:dd:c25:c25:94de:2f30/1282c19:dd:d9:dd:c25:c25:94de:2f30
502c19:dd:d9:dd:c25:c25:94de:2f31/1282c19:dd:d9:dd:c25:c25:94de:2f31
512c19:dd:d9:dd:c25:c25:94de:2f32/1282c19:dd:d9:dd:c25:c25:94de:2f32
522c19:dd:d9:dd:c25:c25:94de:2f33/1282c19:dd:d9:dd:c25:c25:94de:2f33
532c19:dd:d9:dd:c25:c25:94de:2f34/1282c19:dd:d9:dd:c25:c25:94de:2f34
542c19:dd:d9:dd:c25:c25:94de:2f35/1282c19:dd:d9:dd:c25:c25:94de:2f35
552c19:dd:d9:dd:c25:c25:94de:2f36/1282c19:dd:d9:dd:c25:c25:94de:2f36
562c19:dd:d9:dd:c25:c25:94de:2f37/1282c19:dd:d9:dd:c25:c25:94de:2f37
572c19:dd:d9:dd:c25:c25:94de:2f38/1282c19:dd:d9:dd:c25:c25:94de:2f38
582c19:dd:d9:dd:c25:c25:94de:2f39/1282c19:dd:d9:dd:c25:c25:94de:2f39
592c19:dd:d9:dd:c25:c25:94de:2f3a/1282c19:dd:d9:dd:c25:c25:94de:2f3a
602c19:dd:d9:dd:c25:c25:94de:2f3b/1282c19:dd:d9:dd:c25:c25:94de:2f3b
612c19:dd:d9:dd:c25:c25:94de:2f3c/1282c19:dd:d9:dd:c25:c25:94de:2f3c
622c19:dd:d9:dd:c25:c25:94de:2f3d/1282c19:dd:d9:dd:c25:c25:94de:2f3d
632c19:dd:d9:dd:c25:c25:94de:2f3e/1282c19:dd:d9:dd:c25:c25:94de:2f3e
642c19:dd:d9:dd:c25:c25:94de:2f3f/1282c19:dd:d9:dd:c25:c25:94de:2f3f
652c19:dd:d9:dd:c25:c25:94de:2f40/1282c19:dd:d9:dd:c25:c25:94de:2f40
662c19:dd:d9:dd:c25:c25:94de:2f41/1282c19:dd:d9:dd:c25:c25:94de:2f41
672c19:dd:d9:dd:c25:c25:94de:2f42/1282c19:dd:d9:dd:c25:c25:94de:2f42
682c19:dd:d9:dd:c25:c25:94de:2f43/1282c19:dd:d9:dd:c25:c25:94de:2f43
692c19:dd:d9:dd:c25:c25:94de:2f44/1282c19:dd:d9:dd:c25:c25:94de:2f44
702c19:dd:d9:dd:c25:c25:94de:2f45/1282c19:dd:d9:dd:c25:c25:94de:2f45
712c19:dd:d9:dd:c25:c25:94de:2f46/1282c19:dd:d9:dd:c25:c25:94de:2f46
722c19:dd:d9:dd:c25:c25:94de:2f47/1282c19:dd:d9:dd:c25:c25:94de:2f47
732c19:dd:d9:dd:c25:c25:94de:2f48/1282c19:dd:d9:dd:c25:c25:94de:2f48
742c19:dd:d9:dd:c25:c25:94de:2f49/1282c19:dd:d9:dd:c25:c25:94de:2f49
752c19:dd:d9:dd:c25:c25:94de:2f4a/1282c19:dd:d9:dd:c25:c25:94de:2f4a
762c19:dd:d9:dd:c25:c25:94de:2f4b/1282c19:dd:d9:dd:c25:c25:94de:2f4b
772c19:dd:d9:dd:c25:c25:94de:2f4c/1282c19:dd:d9:dd:c25:c25:94de:2f4c
782c19:dd:d9:dd:c25:c25:94de:2f4d/1282c19:dd:d9:dd:c25:c25:94de:2f4d
792c19:dd:d9:dd:c25:c25:94de:2f4e/1282c19:dd:d9:dd:c25:c25:94de:2f4e
802c19:dd:d9:dd:c25:c25:94de:2f4f/1282c19:dd:d9:dd:c25:c25:94de:2f4f
812c19:dd:d9:dd:c25:c25:94de:2f50/1282c19:dd:d9:dd:c25:c25:94de:2f50
822c19:dd:d9:dd:c25:c25:94de:2f51/1282c19:dd:d9:dd:c25:c25:94de:2f51
832c19:dd:d9:dd:c25:c25:94de:2f52/1282c19:dd:d9:dd:c25:c25:94de:2f52
842c19:dd:d9:dd:c25:c25:94de:2f53/1282c19:dd:d9:dd:c25:c25:94de:2f53
852c19:dd:d9:dd:c25:c25:94de:2f54/1282c19:dd:d9:dd:c25:c25:94de:2f54
862c19:dd:d9:dd:c25:c25:94de:2f55/1282c19:dd:d9:dd:c25:c25:94de:2f55
872c19:dd:d9:dd:c25:c25:94de:2f56/1282c19:dd:d9:dd:c25:c25:94de:2f56
882c19:dd:d9:dd:c25:c25:94de:2f57/1282c19:dd:d9:dd:c25:c25:94de:2f57
892c19:dd:d9:dd:c25:c25:94de:2f58/1282c19:dd:d9:dd:c25:c25:94de:2f58
902c19:dd:d9:dd:c25:c25:94de:2f59/1282c19:dd:d9:dd:c25:c25:94de:2f59
912c19:dd:d9:dd:c25:c25:94de:2f5a/1282c19:dd:d9:dd:c25:c25:94de:2f5a
922c19:dd:d9:dd:c25:c25:94de:2f5b/1282c19:dd:d9:dd:c25:c25:94de:2f5b
932c19:dd:d9:dd:c25:c25:94de:2f5c/1282c19:dd:d9:dd:c25:c25:94de:2f5c
942c19:dd:d9:dd:c25:c25:94de:2f5d/1282c19:dd:d9:dd:c25:c25:94de:2f5d
952c19:dd:d9:dd:c25:c25:94de:2f5e/1282c19:dd:d9:dd:c25:c25:94de:2f5e
962c19:dd:d9:dd:c25:c25:94de:2f5f/1282c19:dd:d9:dd:c25:c25:94de:2f5f
972c19:dd:d9:dd:c25:c25:94de:2f60/1282c19:dd:d9:dd:c25:c25:94de:2f60
982c19:dd:d9:dd:c25:c25:94de:2f61/1282c19:dd:d9:dd:c25:c25:94de:2f61
992c19:dd:d9:dd:c25:c25:94de:2f62/1282c19:dd:d9:dd:c25:c25:94de:2f62
1002c19:dd:d9:dd:c25:c25:94de:2f63/1282c19:dd:d9:dd:c25:c25:94de:2f63
1012c19:dd:d9:dd:c25:c25:94de:2f64/1282c19:dd:d9:dd:c25:c25:94de:2f64
1022c19:dd:d9:dd:c25:c25:94de:2f65/1282c19:dd:d9:dd:c25:c25:94de:2f65
1032c19:dd:d9:dd:c25:c25:94de:2f66/1282c19:dd:d9:dd:c25:c25:94de:2f66
1042c19:dd:d9:dd:c25:c25:94de:2f67/1282c19:dd:d9:dd:c25:c25:94de:2f67
1052c19:dd:d9:dd:c25:c25:94de:2f68/1282c19:dd:d9:dd:c25:c25:94de:2f68
1062c19:dd:d9:dd:c25:c25:94de:2f69/1282c19:dd:d9:dd:c25:c25:94de:2f69
1072c19:dd:d9:dd:c25:c25:94de:2f6a/1282c19:dd:d9:dd:c25:c25:94de:2f6a
1082c19:dd:d9:dd:c25:c25:94de:2f6b/1282c19:dd:d9:dd:c25:c25:94de:2f6b
1092c19:dd:d9:dd:c25:c25:94de:2f6c/1282c19:dd:d9:dd:c25:c25:94de:2f6c
1102c19:dd:d9:dd:c25:c25:94de:2f6d/1282c19:dd:d9:dd:c25:c25:94de:2f6d
1112c19:dd:d9:dd:c25:c25:94de:2f6e/1282c19:dd:d9:dd:c25:c25:94de:2f6e
1122c19:dd:d9:dd:c25:c25:94de:2f6f/1282c19:dd:d9:dd:c25:c25:94de:2f6f
1132c19:dd:d9:dd:c25:c25:94de:2f70/1282c19:dd:d9:dd:c25:c25:94de:2f70
1142c19:dd:d9:dd:c25:c25:94de:2f71/1282c19:dd:d9:dd:c25:c25:94de:2f71
1152c19:dd:d9:dd:c25:c25:94de:2f72/1282c19:dd:d9:dd:c25:c25:94de:2f72
1162c19:dd:d9:dd:c25:c25:94de:2f73/1282c19:dd:d9:dd:c25:c25:94de:2f73
1172c19:dd:d9:dd:c25:c25:94de:2f74/1282c19:dd:d9:dd:c25:c25:94de:2f74
1182c19:dd:d9:dd:c25:c25:94de:2f75/1282c19:dd:d9:dd:c25:c25:94de:2f75
1192c19:dd:d9:dd:c25:c25:94de:2f76/1282c19:dd:d9:dd:c25:c25:94de:2f76
1202c19:dd:d9:dd:c25:c25:94de:2f77/1282c19:dd:d9:dd:c25:c25:94de:2f77
1212c19:dd:d9:dd:c25:c25:94de:2f78/1282c19:dd:d9:dd:c25:c25:94de:2f78
1222c19:dd:d9:dd:c25:c25:94de:2f79/1282c19:dd:d9:dd:c25:c25:94de:2f79
1232c19:dd:d9:dd:c25:c25:94de:2f7a/1282c19:dd:d9:dd:c25:c25:94de:2f7a
1242c19:dd:d9:dd:c25:c25:94de:2f7b/1282c19:dd:d9:dd:c25:c25:94de:2f7b
1252c19:dd:d9:dd:c25:c25:94de:2f7c/1282c19:dd:d9:dd:c25:c25:94de:2f7c
1262c19:dd:d9:dd:c25:c25:94de:2f7d/1282c19:dd:d9:dd:c25:c25:94de:2f7d
1272c19:dd:d9:dd:c25:c25:94de:2f7e/1282c19:dd:d9:dd:c25:c25:94de:2f7e
1282c19:dd:d9:dd:c25:c25:94de:2f7f/1282c19:dd:d9:dd:c25:c25:94de:2f7f
1292c19:dd:d9:dd:c25:c25:94de:2f80/1282c19:dd:d9:dd:c25:c25:94de:2f80
1302c19:dd:d9:dd:c25:c25:94de:2f81/1282c19:dd:d9:dd:c25:c25:94de:2f81
1312c19:dd:d9:dd:c25:c25:94de:2f82/1282c19:dd:d9:dd:c25:c25:94de:2f82
1322c19:dd:d9:dd:c25:c25:94de:2f83/1282c19:dd:d9:dd:c25:c25:94de:2f83
1332c19:dd:d9:dd:c25:c25:94de:2f84/1282c19:dd:d9:dd:c25:c25:94de:2f84
1342c19:dd:d9:dd:c25:c25:94de:2f85/1282c19:dd:d9:dd:c25:c25:94de:2f85
1352c19:dd:d9:dd:c25:c25:94de:2f86/1282c19:dd:d9:dd:c25:c25:94de:2f86
1362c19:dd:d9:dd:c25:c25:94de:2f87/1282c19:dd:d9:dd:c25:c25:94de:2f87
1372c19:dd:d9:dd:c25:c25:94de:2f88/1282c19:dd:d9:dd:c25:c25:94de:2f88
1382c19:dd:d9:dd:c25:c25:94de:2f89/1282c19:dd:d9:dd:c25:c25:94de:2f89
1392c19:dd:d9:dd:c25:c25:94de:2f8a/1282c19:dd:d9:dd:c25:c25:94de:2f8a
1402c19:dd:d9:dd:c25:c25:94de:2f8b/1282c19:dd:d9:dd:c25:c25:94de:2f8b
1412c19:dd:d9:dd:c25:c25:94de:2f8c/1282c19:dd:d9:dd:c25:c25:94de:2f8c
1422c19:dd:d9:dd:c25:c25:94de:2f8d/1282c19:dd:d9:dd:c25:c25:94de:2f8d
1432c19:dd:d9:dd:c25:c25:94de:2f8e/1282c19:dd:d9:dd:c25:c25:94de:2f8e
1442c19:dd:d9:dd:c25:c25:94de:2f8f/1282c19:dd:d9:dd:c25:c25:94de:2f8f
1452c19:dd:d9:dd:c25:c25:94de:2f90/1282c19:dd:d9:dd:c25:c25:94de:2f90
1462c19:dd:d9:dd:c25:c25:94de:2f91/1282c19:dd:d9:dd:c25:c25:94de:2f91
1472c19:dd:d9:dd:c25:c25:94de:2f92/1282c19:dd:d9:dd:c25:c25:94de:2f92
1482c19:dd:d9:dd:c25:c25:94de:2f93/1282c19:dd:d9:dd:c25:c25:94de:2f93
1492c19:dd:d9:dd:c25:c25:94de:2f94/1282c19:dd:d9:dd:c25:c25:94de:2f94
1502c19:dd:d9:dd:c25:c25:94de:2f95/1282c19:dd:d9:dd:c25:c25:94de:2f95
1512c19:dd:d9:dd:c25:c25:94de:2f96/1282c19:dd:d9:dd:c25:c25:94de:2f96
1522c19:dd:d9:dd:c25:c25:94de:2f97/1282c19:dd:d9:dd:c25:c25:94de:2f97
1532c19:dd:d9:dd:c25:c25:94de:2f98/1282c19:dd:d9:dd:c25:c25:94de:2f98
1542c19:dd:d9:dd:c25:c25:94de:2f99/1282c19:dd:d9:dd:c25:c25:94de:2f99
1552c19:dd:d9:dd:c25:c25:94de:2f9a/1282c19:dd:d9:dd:c25:c25:94de:2f9a
1562c19:dd:d9:dd:c25:c25:94de:2f9b/1282c19:dd:d9:dd:c25:c25:94de:2f9b
1572c19:dd:d9:dd:c25:c25:94de:2f9c/1282c19:dd:d9:dd:c25:c25:94de:2f9c
1582c19:dd:d9:dd:c25:c25:94de:2f9d/1282c19:dd:d9:dd:c25:c25:94de:2f9d
1592c19:dd:d9:dd:c25:c25:94de:2f9e/1282c19:dd:d9:dd:c25:c25:94de:2f9e
1602c19:dd:d9:dd:c25:c25:94de:2f9f/1282c19:dd:d9:dd:c25:c25:94de:2f9f
1612c19:dd:d9:dd:c25:c25:94de:2fa0/1282c19:dd:d9:dd:c25:c25:94de:2fa0
1622c19:dd:d9:dd:c25:c25:94de:2fa1/1282c19:dd:d9:dd:c25:c25:94de:2fa1
1632c19:dd:d9:dd:c25:c25:94de:2fa2/1282c19:dd:d9:dd:c25:c25:94de:2fa2
1642c19:dd:d9:dd:c25:c25:94de:2fa3/1282c19:dd:d9:dd:c25:c25:94de:2fa3
1652c19:dd:d9:dd:c25:c25:94de:2fa4/1282c19:dd:d9:dd:c25:c25:94de:2fa4
1662c19:dd:d9:dd:c25:c25:94de:2fa5/1282c19:dd:d9:dd:c25:c25:94de:2fa5
1672c19:dd:d9:dd:c25:c25:94de:2fa6/1282c19:dd:d9:dd:c25:c25:94de:2fa6
1682c19:dd:d9:dd:c25:c25:94de:2fa7/1282c19:dd:d9:dd:c25:c25:94de:2fa7
1692c19:dd:d9:dd:c25:c25:94de:2fa8/1282c19:dd:d9:dd:c25:c25:94de:2fa8
1702c19:dd:d9:dd:c25:c25:94de:2fa9/1282c19:dd:d9:dd:c25:c25:94de:2fa9
1712c19:dd:d9:dd:c25:c25:94de:2faa/1282c19:dd:d9:dd:c25:c25:94de:2faa
1722c19:dd:d9:dd:c25:c25:94de:2fab/1282c19:dd:d9:dd:c25:c25:94de:2fab
1732c19:dd:d9:dd:c25:c25:94de:2fac/1282c19:dd:d9:dd:c25:c25:94de:2fac
1742c19:dd:d9:dd:c25:c25:94de:2fad/1282c19:dd:d9:dd:c25:c25:94de:2fad
1752c19:dd:d9:dd:c25:c25:94de:2fae/1282c19:dd:d9:dd:c25:c25:94de:2fae
1762c19:dd:d9:dd:c25:c25:94de:2faf/1282c19:dd:d9:dd:c25:c25:94de:2faf
1772c19:dd:d9:dd:c25:c25:94de:2fb0/1282c19:dd:d9:dd:c25:c25:94de:2fb0
1782c19:dd:d9:dd:c25:c25:94de:2fb1/1282c19:dd:d9:dd:c25:c25:94de:2fb1
1792c19:dd:d9:dd:c25:c25:94de:2fb2/1282c19:dd:d9:dd:c25:c25:94de:2fb2
1802c19:dd:d9:dd:c25:c25:94de:2fb3/1282c19:dd:d9:dd:c25:c25:94de:2fb3
1812c19:dd:d9:dd:c25:c25:94de:2fb4/1282c19:dd:d9:dd:c25:c25:94de:2fb4
1822c19:dd:d9:dd:c25:c25:94de:2fb5/1282c19:dd:d9:dd:c25:c25:94de:2fb5
1832c19:dd:d9:dd:c25:c25:94de:2fb6/1282c19:dd:d9:dd:c25:c25:94de:2fb6
1842c19:dd:d9:dd:c25:c25:94de:2fb7/1282c19:dd:d9:dd:c25:c25:94de:2fb7
1852c19:dd:d9:dd:c25:c25:94de:2fb8/1282c19:dd:d9:dd:c25:c25:94de:2fb8
1862c19:dd:d9:dd:c25:c25:94de:2fb9/1282c19:dd:d9:dd:c25:c25:94de:2fb9
1872c19:dd:d9:dd:c25:c25:94de:2fba/1282c19:dd:d9:dd:c25:c25:94de:2fba
1882c19:dd:d9:dd:c25:c25:94de:2fbb/1282c19:dd:d9:dd:c25:c25:94de:2fbb
1892c19:dd:d9:dd:c25:c25:94de:2fbc/1282c19:dd:d9:dd:c25:c25:94de:2fbc
1902c19:dd:d9:dd:c25:c25:94de:2fbd/1282c19:dd:d9:dd:c25:c25:94de:2fbd
1912c19:dd:d9:dd:c25:c25:94de:2fbe/1282c19:dd:d9:dd:c25:c25:94de:2fbe
1922c19:dd:d9:dd:c25:c25:94de:2fbf/1282c19:dd:d9:dd:c25:c25:94de:2fbf
1932c19:dd:d9:dd:c25:c25:94de:2fc0/1282c19:dd:d9:dd:c25:c25:94de:2fc0
1942c19:dd:d9:dd:c25:c25:94de:2fc1/1282c19:dd:d9:dd:c25:c25:94de:2fc1
1952c19:dd:d9:dd:c25:c25:94de:2fc2/1282c19:dd:d9:dd:c25:c25:94de:2fc2
1962c19:dd:d9:dd:c25:c25:94de:2fc3/1282c19:dd:d9:dd:c25:c25:94de:2fc3
1972c19:dd:d9:dd:c25:c25:94de:2fc4/1282c19:dd:d9:dd:c25:c25:94de:2fc4
1982c19:dd:d9:dd:c25:c25:94de:2fc5/1282c19:dd:d9:dd:c25:c25:94de:2fc5
1992c19:dd:d9:dd:c25:c25:94de:2fc6/1282c19:dd:d9:dd:c25:c25:94de:2fc6
2002c19:dd:d9:dd:c25:c25:94de:2fc7/1282c19:dd:d9:dd:c25:c25:94de:2fc7
2012c19:dd:d9:dd:c25:c25:94de:2fc8/1282c19:dd:d9:dd:c25:c25:94de:2fc8
2022c19:dd:d9:dd:c25:c25:94de:2fc9/1282c19:dd:d9:dd:c25:c25:94de:2fc9
2032c19:dd:d9:dd:c25:c25:94de:2fca/1282c19:dd:d9:dd:c25:c25:94de:2fca
2042c19:dd:d9:dd:c25:c25:94de:2fcb/1282c19:dd:d9:dd:c25:c25:94de:2fcb
2052c19:dd:d9:dd:c25:c25:94de:2fcc/1282c19:dd:d9:dd:c25:c25:94de:2fcc
2062c19:dd:d9:dd:c25:c25:94de:2fcd/1282c19:dd:d9:dd:c25:c25:94de:2fcd
2072c19:dd:d9:dd:c25:c25:94de:2fce/1282c19:dd:d9:dd:c25:c25:94de:2fce
2082c19:dd:d9:dd:c25:c25:94de:2fcf/1282c19:dd:d9:dd:c25:c25:94de:2fcf
2092c19:dd:d9:dd:c25:c25:94de:2fd0/1282c19:dd:d9:dd:c25:c25:94de:2fd0
2102c19:dd:d9:dd:c25:c25:94de:2fd1/1282c19:dd:d9:dd:c25:c25:94de:2fd1
2112c19:dd:d9:dd:c25:c25:94de:2fd2/1282c19:dd:d9:dd:c25:c25:94de:2fd2
2122c19:dd:d9:dd:c25:c25:94de:2fd3/1282c19:dd:d9:dd:c25:c25:94de:2fd3
2132c19:dd:d9:dd:c25:c25:94de:2fd4/1282c19:dd:d9:dd:c25:c25:94de:2fd4
2142c19:dd:d9:dd:c25:c25:94de:2fd5/1282c19:dd:d9:dd:c25:c25:94de:2fd5
2152c19:dd:d9:dd:c25:c25:94de:2fd6/1282c19:dd:d9:dd:c25:c25:94de:2fd6
2162c19:dd:d9:dd:c25:c25:94de:2fd7/1282c19:dd:d9:dd:c25:c25:94de:2fd7
2172c19:dd:d9:dd:c25:c25:94de:2fd8/1282c19:dd:d9:dd:c25:c25:94de:2fd8
2182c19:dd:d9:dd:c25:c25:94de:2fd9/1282c19:dd:d9:dd:c25:c25:94de:2fd9
2192c19:dd:d9:dd:c25:c25:94de:2fda/1282c19:dd:d9:dd:c25:c25:94de:2fda
2202c19:dd:d9:dd:c25:c25:94de:2fdb/1282c19:dd:d9:dd:c25:c25:94de:2fdb
2212c19:dd:d9:dd:c25:c25:94de:2fdc/1282c19:dd:d9:dd:c25:c25:94de:2fdc
2222c19:dd:d9:dd:c25:c25:94de:2fdd/1282c19:dd:d9:dd:c25:c25:94de:2fdd
2232c19:dd:d9:dd:c25:c25:94de:2fde/1282c19:dd:d9:dd:c25:c25:94de:2fde
2242c19:dd:d9:dd:c25:c25:94de:2fdf/1282c19:dd:d9:dd:c25:c25:94de:2fdf
2252c19:dd:d9:dd:c25:c25:94de:2fe0/1282c19:dd:d9:dd:c25:c25:94de:2fe0
2262c19:dd:d9:dd:c25:c25:94de:2fe1/1282c19:dd:d9:dd:c25:c25:94de:2fe1
2272c19:dd:d9:dd:c25:c25:94de:2fe2/1282c19:dd:d9:dd:c25:c25:94de:2fe2
2282c19:dd:d9:dd:c25:c25:94de:2fe3/1282c19:dd:d9:dd:c25:c25:94de:2fe3
2292c19:dd:d9:dd:c25:c25:94de:2fe4/1282c19:dd:d9:dd:c25:c25:94de:2fe4
2302c19:dd:d9:dd:c25:c25:94de:2fe5/1282c19:dd:d9:dd:c25:c25:94de:2fe5
2312c19:dd:d9:dd:c25:c25:94de:2fe6/1282c19:dd:d9:dd:c25:c25:94de:2fe6
2322c19:dd:d9:dd:c25:c25:94de:2fe7/1282c19:dd:d9:dd:c25:c25:94de:2fe7
2332c19:dd:d9:dd:c25:c25:94de:2fe8/1282c19:dd:d9:dd:c25:c25:94de:2fe8
2342c19:dd:d9:dd:c25:c25:94de:2fe9/1282c19:dd:d9:dd:c25:c25:94de:2fe9
2352c19:dd:d9:dd:c25:c25:94de:2fea/1282c19:dd:d9:dd:c25:c25:94de:2fea
2362c19:dd:d9:dd:c25:c25:94de:2feb/1282c19:dd:d9:dd:c25:c25:94de:2feb
2372c19:dd:d9:dd:c25:c25:94de:2fec/1282c19:dd:d9:dd:c25:c25:94de:2fec
2382c19:dd:d9:dd:c25:c25:94de:2fed/1282c19:dd:d9:dd:c25:c25:94de:2fed
2392c19:dd:d9:dd:c25:c25:94de:2fee/1282c19:dd:d9:dd:c25:c25:94de:2fee
2402c19:dd:d9:dd:c25:c25:94de:2fef/1282c19:dd:d9:dd:c25:c25:94de:2fef
2412c19:dd:d9:dd:c25:c25:94de:2ff0/1282c19:dd:d9:dd:c25:c25:94de:2ff0
2422c19:dd:d9:dd:c25:c25:94de:2ff1/1282c19:dd:d9:dd:c25:c25:94de:2ff1
2432c19:dd:d9:dd:c25:c25:94de:2ff2/1282c19:dd:d9:dd:c25:c25:94de:2ff2
2442c19:dd:d9:dd:c25:c25:94de:2ff3/1282c19:dd:d9:dd:c25:c25:94de:2ff3
2452c19:dd:d9:dd:c25:c25:94de:2ff4/1282c19:dd:d9:dd:c25:c25:94de:2ff4
2462c19:dd:d9:dd:c25:c25:94de:2ff5/1282c19:dd:d9:dd:c25:c25:94de:2ff5
2472c19:dd:d9:dd:c25:c25:94de:2ff6/1282c19:dd:d9:dd:c25:c25:94de:2ff6
2482c19:dd:d9:dd:c25:c25:94de:2ff7/1282c19:dd:d9:dd:c25:c25:94de:2ff7
2492c19:dd:d9:dd:c25:c25:94de:2ff8/1282c19:dd:d9:dd:c25:c25:94de:2ff8
2502c19:dd:d9:dd:c25:c25:94de:2ff9/1282c19:dd:d9:dd:c25:c25:94de:2ff9
2512c19:dd:d9:dd:c25:c25:94de:2ffa/1282c19:dd:d9:dd:c25:c25:94de:2ffa
2522c19:dd:d9:dd:c25:c25:94de:2ffb/1282c19:dd:d9:dd:c25:c25:94de:2ffb
2532c19:dd:d9:dd:c25:c25:94de:2ffc/1282c19:dd:d9:dd:c25:c25:94de:2ffc
2542c19:dd:d9:dd:c25:c25:94de:2ffd/1282c19:dd:d9:dd:c25:c25:94de:2ffd
2552c19:dd:d9:dd:c25:c25:94de:2ffe/1282c19:dd:d9:dd:c25:c25:94de:2ffe
2562c19:dd:d9:dd:c25:c25:94de:2fff/1282c19:dd:d9:dd:c25:c25:94de:2fff

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.