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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:d915:7f00/120
First address
2c19:dd:d9:dd:c25:c25:d915:7f00
Last address
2c19:dd:d9:dd:c25:c25:d915:7fff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:d915:7f00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
f.7.5.1.9.d.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:d915:7f00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:d915:7f00/1282c19:dd:d9:dd:c25:c25:d915:7f00
22c19:dd:d9:dd:c25:c25:d915:7f01/1282c19:dd:d9:dd:c25:c25:d915:7f01
32c19:dd:d9:dd:c25:c25:d915:7f02/1282c19:dd:d9:dd:c25:c25:d915:7f02
42c19:dd:d9:dd:c25:c25:d915:7f03/1282c19:dd:d9:dd:c25:c25:d915:7f03
52c19:dd:d9:dd:c25:c25:d915:7f04/1282c19:dd:d9:dd:c25:c25:d915:7f04
62c19:dd:d9:dd:c25:c25:d915:7f05/1282c19:dd:d9:dd:c25:c25:d915:7f05
72c19:dd:d9:dd:c25:c25:d915:7f06/1282c19:dd:d9:dd:c25:c25:d915:7f06
82c19:dd:d9:dd:c25:c25:d915:7f07/1282c19:dd:d9:dd:c25:c25:d915:7f07
92c19:dd:d9:dd:c25:c25:d915:7f08/1282c19:dd:d9:dd:c25:c25:d915:7f08
102c19:dd:d9:dd:c25:c25:d915:7f09/1282c19:dd:d9:dd:c25:c25:d915:7f09
112c19:dd:d9:dd:c25:c25:d915:7f0a/1282c19:dd:d9:dd:c25:c25:d915:7f0a
122c19:dd:d9:dd:c25:c25:d915:7f0b/1282c19:dd:d9:dd:c25:c25:d915:7f0b
132c19:dd:d9:dd:c25:c25:d915:7f0c/1282c19:dd:d9:dd:c25:c25:d915:7f0c
142c19:dd:d9:dd:c25:c25:d915:7f0d/1282c19:dd:d9:dd:c25:c25:d915:7f0d
152c19:dd:d9:dd:c25:c25:d915:7f0e/1282c19:dd:d9:dd:c25:c25:d915:7f0e
162c19:dd:d9:dd:c25:c25:d915:7f0f/1282c19:dd:d9:dd:c25:c25:d915:7f0f
172c19:dd:d9:dd:c25:c25:d915:7f10/1282c19:dd:d9:dd:c25:c25:d915:7f10
182c19:dd:d9:dd:c25:c25:d915:7f11/1282c19:dd:d9:dd:c25:c25:d915:7f11
192c19:dd:d9:dd:c25:c25:d915:7f12/1282c19:dd:d9:dd:c25:c25:d915:7f12
202c19:dd:d9:dd:c25:c25:d915:7f13/1282c19:dd:d9:dd:c25:c25:d915:7f13
212c19:dd:d9:dd:c25:c25:d915:7f14/1282c19:dd:d9:dd:c25:c25:d915:7f14
222c19:dd:d9:dd:c25:c25:d915:7f15/1282c19:dd:d9:dd:c25:c25:d915:7f15
232c19:dd:d9:dd:c25:c25:d915:7f16/1282c19:dd:d9:dd:c25:c25:d915:7f16
242c19:dd:d9:dd:c25:c25:d915:7f17/1282c19:dd:d9:dd:c25:c25:d915:7f17
252c19:dd:d9:dd:c25:c25:d915:7f18/1282c19:dd:d9:dd:c25:c25:d915:7f18
262c19:dd:d9:dd:c25:c25:d915:7f19/1282c19:dd:d9:dd:c25:c25:d915:7f19
272c19:dd:d9:dd:c25:c25:d915:7f1a/1282c19:dd:d9:dd:c25:c25:d915:7f1a
282c19:dd:d9:dd:c25:c25:d915:7f1b/1282c19:dd:d9:dd:c25:c25:d915:7f1b
292c19:dd:d9:dd:c25:c25:d915:7f1c/1282c19:dd:d9:dd:c25:c25:d915:7f1c
302c19:dd:d9:dd:c25:c25:d915:7f1d/1282c19:dd:d9:dd:c25:c25:d915:7f1d
312c19:dd:d9:dd:c25:c25:d915:7f1e/1282c19:dd:d9:dd:c25:c25:d915:7f1e
322c19:dd:d9:dd:c25:c25:d915:7f1f/1282c19:dd:d9:dd:c25:c25:d915:7f1f
332c19:dd:d9:dd:c25:c25:d915:7f20/1282c19:dd:d9:dd:c25:c25:d915:7f20
342c19:dd:d9:dd:c25:c25:d915:7f21/1282c19:dd:d9:dd:c25:c25:d915:7f21
352c19:dd:d9:dd:c25:c25:d915:7f22/1282c19:dd:d9:dd:c25:c25:d915:7f22
362c19:dd:d9:dd:c25:c25:d915:7f23/1282c19:dd:d9:dd:c25:c25:d915:7f23
372c19:dd:d9:dd:c25:c25:d915:7f24/1282c19:dd:d9:dd:c25:c25:d915:7f24
382c19:dd:d9:dd:c25:c25:d915:7f25/1282c19:dd:d9:dd:c25:c25:d915:7f25
392c19:dd:d9:dd:c25:c25:d915:7f26/1282c19:dd:d9:dd:c25:c25:d915:7f26
402c19:dd:d9:dd:c25:c25:d915:7f27/1282c19:dd:d9:dd:c25:c25:d915:7f27
412c19:dd:d9:dd:c25:c25:d915:7f28/1282c19:dd:d9:dd:c25:c25:d915:7f28
422c19:dd:d9:dd:c25:c25:d915:7f29/1282c19:dd:d9:dd:c25:c25:d915:7f29
432c19:dd:d9:dd:c25:c25:d915:7f2a/1282c19:dd:d9:dd:c25:c25:d915:7f2a
442c19:dd:d9:dd:c25:c25:d915:7f2b/1282c19:dd:d9:dd:c25:c25:d915:7f2b
452c19:dd:d9:dd:c25:c25:d915:7f2c/1282c19:dd:d9:dd:c25:c25:d915:7f2c
462c19:dd:d9:dd:c25:c25:d915:7f2d/1282c19:dd:d9:dd:c25:c25:d915:7f2d
472c19:dd:d9:dd:c25:c25:d915:7f2e/1282c19:dd:d9:dd:c25:c25:d915:7f2e
482c19:dd:d9:dd:c25:c25:d915:7f2f/1282c19:dd:d9:dd:c25:c25:d915:7f2f
492c19:dd:d9:dd:c25:c25:d915:7f30/1282c19:dd:d9:dd:c25:c25:d915:7f30
502c19:dd:d9:dd:c25:c25:d915:7f31/1282c19:dd:d9:dd:c25:c25:d915:7f31
512c19:dd:d9:dd:c25:c25:d915:7f32/1282c19:dd:d9:dd:c25:c25:d915:7f32
522c19:dd:d9:dd:c25:c25:d915:7f33/1282c19:dd:d9:dd:c25:c25:d915:7f33
532c19:dd:d9:dd:c25:c25:d915:7f34/1282c19:dd:d9:dd:c25:c25:d915:7f34
542c19:dd:d9:dd:c25:c25:d915:7f35/1282c19:dd:d9:dd:c25:c25:d915:7f35
552c19:dd:d9:dd:c25:c25:d915:7f36/1282c19:dd:d9:dd:c25:c25:d915:7f36
562c19:dd:d9:dd:c25:c25:d915:7f37/1282c19:dd:d9:dd:c25:c25:d915:7f37
572c19:dd:d9:dd:c25:c25:d915:7f38/1282c19:dd:d9:dd:c25:c25:d915:7f38
582c19:dd:d9:dd:c25:c25:d915:7f39/1282c19:dd:d9:dd:c25:c25:d915:7f39
592c19:dd:d9:dd:c25:c25:d915:7f3a/1282c19:dd:d9:dd:c25:c25:d915:7f3a
602c19:dd:d9:dd:c25:c25:d915:7f3b/1282c19:dd:d9:dd:c25:c25:d915:7f3b
612c19:dd:d9:dd:c25:c25:d915:7f3c/1282c19:dd:d9:dd:c25:c25:d915:7f3c
622c19:dd:d9:dd:c25:c25:d915:7f3d/1282c19:dd:d9:dd:c25:c25:d915:7f3d
632c19:dd:d9:dd:c25:c25:d915:7f3e/1282c19:dd:d9:dd:c25:c25:d915:7f3e
642c19:dd:d9:dd:c25:c25:d915:7f3f/1282c19:dd:d9:dd:c25:c25:d915:7f3f
652c19:dd:d9:dd:c25:c25:d915:7f40/1282c19:dd:d9:dd:c25:c25:d915:7f40
662c19:dd:d9:dd:c25:c25:d915:7f41/1282c19:dd:d9:dd:c25:c25:d915:7f41
672c19:dd:d9:dd:c25:c25:d915:7f42/1282c19:dd:d9:dd:c25:c25:d915:7f42
682c19:dd:d9:dd:c25:c25:d915:7f43/1282c19:dd:d9:dd:c25:c25:d915:7f43
692c19:dd:d9:dd:c25:c25:d915:7f44/1282c19:dd:d9:dd:c25:c25:d915:7f44
702c19:dd:d9:dd:c25:c25:d915:7f45/1282c19:dd:d9:dd:c25:c25:d915:7f45
712c19:dd:d9:dd:c25:c25:d915:7f46/1282c19:dd:d9:dd:c25:c25:d915:7f46
722c19:dd:d9:dd:c25:c25:d915:7f47/1282c19:dd:d9:dd:c25:c25:d915:7f47
732c19:dd:d9:dd:c25:c25:d915:7f48/1282c19:dd:d9:dd:c25:c25:d915:7f48
742c19:dd:d9:dd:c25:c25:d915:7f49/1282c19:dd:d9:dd:c25:c25:d915:7f49
752c19:dd:d9:dd:c25:c25:d915:7f4a/1282c19:dd:d9:dd:c25:c25:d915:7f4a
762c19:dd:d9:dd:c25:c25:d915:7f4b/1282c19:dd:d9:dd:c25:c25:d915:7f4b
772c19:dd:d9:dd:c25:c25:d915:7f4c/1282c19:dd:d9:dd:c25:c25:d915:7f4c
782c19:dd:d9:dd:c25:c25:d915:7f4d/1282c19:dd:d9:dd:c25:c25:d915:7f4d
792c19:dd:d9:dd:c25:c25:d915:7f4e/1282c19:dd:d9:dd:c25:c25:d915:7f4e
802c19:dd:d9:dd:c25:c25:d915:7f4f/1282c19:dd:d9:dd:c25:c25:d915:7f4f
812c19:dd:d9:dd:c25:c25:d915:7f50/1282c19:dd:d9:dd:c25:c25:d915:7f50
822c19:dd:d9:dd:c25:c25:d915:7f51/1282c19:dd:d9:dd:c25:c25:d915:7f51
832c19:dd:d9:dd:c25:c25:d915:7f52/1282c19:dd:d9:dd:c25:c25:d915:7f52
842c19:dd:d9:dd:c25:c25:d915:7f53/1282c19:dd:d9:dd:c25:c25:d915:7f53
852c19:dd:d9:dd:c25:c25:d915:7f54/1282c19:dd:d9:dd:c25:c25:d915:7f54
862c19:dd:d9:dd:c25:c25:d915:7f55/1282c19:dd:d9:dd:c25:c25:d915:7f55
872c19:dd:d9:dd:c25:c25:d915:7f56/1282c19:dd:d9:dd:c25:c25:d915:7f56
882c19:dd:d9:dd:c25:c25:d915:7f57/1282c19:dd:d9:dd:c25:c25:d915:7f57
892c19:dd:d9:dd:c25:c25:d915:7f58/1282c19:dd:d9:dd:c25:c25:d915:7f58
902c19:dd:d9:dd:c25:c25:d915:7f59/1282c19:dd:d9:dd:c25:c25:d915:7f59
912c19:dd:d9:dd:c25:c25:d915:7f5a/1282c19:dd:d9:dd:c25:c25:d915:7f5a
922c19:dd:d9:dd:c25:c25:d915:7f5b/1282c19:dd:d9:dd:c25:c25:d915:7f5b
932c19:dd:d9:dd:c25:c25:d915:7f5c/1282c19:dd:d9:dd:c25:c25:d915:7f5c
942c19:dd:d9:dd:c25:c25:d915:7f5d/1282c19:dd:d9:dd:c25:c25:d915:7f5d
952c19:dd:d9:dd:c25:c25:d915:7f5e/1282c19:dd:d9:dd:c25:c25:d915:7f5e
962c19:dd:d9:dd:c25:c25:d915:7f5f/1282c19:dd:d9:dd:c25:c25:d915:7f5f
972c19:dd:d9:dd:c25:c25:d915:7f60/1282c19:dd:d9:dd:c25:c25:d915:7f60
982c19:dd:d9:dd:c25:c25:d915:7f61/1282c19:dd:d9:dd:c25:c25:d915:7f61
992c19:dd:d9:dd:c25:c25:d915:7f62/1282c19:dd:d9:dd:c25:c25:d915:7f62
1002c19:dd:d9:dd:c25:c25:d915:7f63/1282c19:dd:d9:dd:c25:c25:d915:7f63
1012c19:dd:d9:dd:c25:c25:d915:7f64/1282c19:dd:d9:dd:c25:c25:d915:7f64
1022c19:dd:d9:dd:c25:c25:d915:7f65/1282c19:dd:d9:dd:c25:c25:d915:7f65
1032c19:dd:d9:dd:c25:c25:d915:7f66/1282c19:dd:d9:dd:c25:c25:d915:7f66
1042c19:dd:d9:dd:c25:c25:d915:7f67/1282c19:dd:d9:dd:c25:c25:d915:7f67
1052c19:dd:d9:dd:c25:c25:d915:7f68/1282c19:dd:d9:dd:c25:c25:d915:7f68
1062c19:dd:d9:dd:c25:c25:d915:7f69/1282c19:dd:d9:dd:c25:c25:d915:7f69
1072c19:dd:d9:dd:c25:c25:d915:7f6a/1282c19:dd:d9:dd:c25:c25:d915:7f6a
1082c19:dd:d9:dd:c25:c25:d915:7f6b/1282c19:dd:d9:dd:c25:c25:d915:7f6b
1092c19:dd:d9:dd:c25:c25:d915:7f6c/1282c19:dd:d9:dd:c25:c25:d915:7f6c
1102c19:dd:d9:dd:c25:c25:d915:7f6d/1282c19:dd:d9:dd:c25:c25:d915:7f6d
1112c19:dd:d9:dd:c25:c25:d915:7f6e/1282c19:dd:d9:dd:c25:c25:d915:7f6e
1122c19:dd:d9:dd:c25:c25:d915:7f6f/1282c19:dd:d9:dd:c25:c25:d915:7f6f
1132c19:dd:d9:dd:c25:c25:d915:7f70/1282c19:dd:d9:dd:c25:c25:d915:7f70
1142c19:dd:d9:dd:c25:c25:d915:7f71/1282c19:dd:d9:dd:c25:c25:d915:7f71
1152c19:dd:d9:dd:c25:c25:d915:7f72/1282c19:dd:d9:dd:c25:c25:d915:7f72
1162c19:dd:d9:dd:c25:c25:d915:7f73/1282c19:dd:d9:dd:c25:c25:d915:7f73
1172c19:dd:d9:dd:c25:c25:d915:7f74/1282c19:dd:d9:dd:c25:c25:d915:7f74
1182c19:dd:d9:dd:c25:c25:d915:7f75/1282c19:dd:d9:dd:c25:c25:d915:7f75
1192c19:dd:d9:dd:c25:c25:d915:7f76/1282c19:dd:d9:dd:c25:c25:d915:7f76
1202c19:dd:d9:dd:c25:c25:d915:7f77/1282c19:dd:d9:dd:c25:c25:d915:7f77
1212c19:dd:d9:dd:c25:c25:d915:7f78/1282c19:dd:d9:dd:c25:c25:d915:7f78
1222c19:dd:d9:dd:c25:c25:d915:7f79/1282c19:dd:d9:dd:c25:c25:d915:7f79
1232c19:dd:d9:dd:c25:c25:d915:7f7a/1282c19:dd:d9:dd:c25:c25:d915:7f7a
1242c19:dd:d9:dd:c25:c25:d915:7f7b/1282c19:dd:d9:dd:c25:c25:d915:7f7b
1252c19:dd:d9:dd:c25:c25:d915:7f7c/1282c19:dd:d9:dd:c25:c25:d915:7f7c
1262c19:dd:d9:dd:c25:c25:d915:7f7d/1282c19:dd:d9:dd:c25:c25:d915:7f7d
1272c19:dd:d9:dd:c25:c25:d915:7f7e/1282c19:dd:d9:dd:c25:c25:d915:7f7e
1282c19:dd:d9:dd:c25:c25:d915:7f7f/1282c19:dd:d9:dd:c25:c25:d915:7f7f
1292c19:dd:d9:dd:c25:c25:d915:7f80/1282c19:dd:d9:dd:c25:c25:d915:7f80
1302c19:dd:d9:dd:c25:c25:d915:7f81/1282c19:dd:d9:dd:c25:c25:d915:7f81
1312c19:dd:d9:dd:c25:c25:d915:7f82/1282c19:dd:d9:dd:c25:c25:d915:7f82
1322c19:dd:d9:dd:c25:c25:d915:7f83/1282c19:dd:d9:dd:c25:c25:d915:7f83
1332c19:dd:d9:dd:c25:c25:d915:7f84/1282c19:dd:d9:dd:c25:c25:d915:7f84
1342c19:dd:d9:dd:c25:c25:d915:7f85/1282c19:dd:d9:dd:c25:c25:d915:7f85
1352c19:dd:d9:dd:c25:c25:d915:7f86/1282c19:dd:d9:dd:c25:c25:d915:7f86
1362c19:dd:d9:dd:c25:c25:d915:7f87/1282c19:dd:d9:dd:c25:c25:d915:7f87
1372c19:dd:d9:dd:c25:c25:d915:7f88/1282c19:dd:d9:dd:c25:c25:d915:7f88
1382c19:dd:d9:dd:c25:c25:d915:7f89/1282c19:dd:d9:dd:c25:c25:d915:7f89
1392c19:dd:d9:dd:c25:c25:d915:7f8a/1282c19:dd:d9:dd:c25:c25:d915:7f8a
1402c19:dd:d9:dd:c25:c25:d915:7f8b/1282c19:dd:d9:dd:c25:c25:d915:7f8b
1412c19:dd:d9:dd:c25:c25:d915:7f8c/1282c19:dd:d9:dd:c25:c25:d915:7f8c
1422c19:dd:d9:dd:c25:c25:d915:7f8d/1282c19:dd:d9:dd:c25:c25:d915:7f8d
1432c19:dd:d9:dd:c25:c25:d915:7f8e/1282c19:dd:d9:dd:c25:c25:d915:7f8e
1442c19:dd:d9:dd:c25:c25:d915:7f8f/1282c19:dd:d9:dd:c25:c25:d915:7f8f
1452c19:dd:d9:dd:c25:c25:d915:7f90/1282c19:dd:d9:dd:c25:c25:d915:7f90
1462c19:dd:d9:dd:c25:c25:d915:7f91/1282c19:dd:d9:dd:c25:c25:d915:7f91
1472c19:dd:d9:dd:c25:c25:d915:7f92/1282c19:dd:d9:dd:c25:c25:d915:7f92
1482c19:dd:d9:dd:c25:c25:d915:7f93/1282c19:dd:d9:dd:c25:c25:d915:7f93
1492c19:dd:d9:dd:c25:c25:d915:7f94/1282c19:dd:d9:dd:c25:c25:d915:7f94
1502c19:dd:d9:dd:c25:c25:d915:7f95/1282c19:dd:d9:dd:c25:c25:d915:7f95
1512c19:dd:d9:dd:c25:c25:d915:7f96/1282c19:dd:d9:dd:c25:c25:d915:7f96
1522c19:dd:d9:dd:c25:c25:d915:7f97/1282c19:dd:d9:dd:c25:c25:d915:7f97
1532c19:dd:d9:dd:c25:c25:d915:7f98/1282c19:dd:d9:dd:c25:c25:d915:7f98
1542c19:dd:d9:dd:c25:c25:d915:7f99/1282c19:dd:d9:dd:c25:c25:d915:7f99
1552c19:dd:d9:dd:c25:c25:d915:7f9a/1282c19:dd:d9:dd:c25:c25:d915:7f9a
1562c19:dd:d9:dd:c25:c25:d915:7f9b/1282c19:dd:d9:dd:c25:c25:d915:7f9b
1572c19:dd:d9:dd:c25:c25:d915:7f9c/1282c19:dd:d9:dd:c25:c25:d915:7f9c
1582c19:dd:d9:dd:c25:c25:d915:7f9d/1282c19:dd:d9:dd:c25:c25:d915:7f9d
1592c19:dd:d9:dd:c25:c25:d915:7f9e/1282c19:dd:d9:dd:c25:c25:d915:7f9e
1602c19:dd:d9:dd:c25:c25:d915:7f9f/1282c19:dd:d9:dd:c25:c25:d915:7f9f
1612c19:dd:d9:dd:c25:c25:d915:7fa0/1282c19:dd:d9:dd:c25:c25:d915:7fa0
1622c19:dd:d9:dd:c25:c25:d915:7fa1/1282c19:dd:d9:dd:c25:c25:d915:7fa1
1632c19:dd:d9:dd:c25:c25:d915:7fa2/1282c19:dd:d9:dd:c25:c25:d915:7fa2
1642c19:dd:d9:dd:c25:c25:d915:7fa3/1282c19:dd:d9:dd:c25:c25:d915:7fa3
1652c19:dd:d9:dd:c25:c25:d915:7fa4/1282c19:dd:d9:dd:c25:c25:d915:7fa4
1662c19:dd:d9:dd:c25:c25:d915:7fa5/1282c19:dd:d9:dd:c25:c25:d915:7fa5
1672c19:dd:d9:dd:c25:c25:d915:7fa6/1282c19:dd:d9:dd:c25:c25:d915:7fa6
1682c19:dd:d9:dd:c25:c25:d915:7fa7/1282c19:dd:d9:dd:c25:c25:d915:7fa7
1692c19:dd:d9:dd:c25:c25:d915:7fa8/1282c19:dd:d9:dd:c25:c25:d915:7fa8
1702c19:dd:d9:dd:c25:c25:d915:7fa9/1282c19:dd:d9:dd:c25:c25:d915:7fa9
1712c19:dd:d9:dd:c25:c25:d915:7faa/1282c19:dd:d9:dd:c25:c25:d915:7faa
1722c19:dd:d9:dd:c25:c25:d915:7fab/1282c19:dd:d9:dd:c25:c25:d915:7fab
1732c19:dd:d9:dd:c25:c25:d915:7fac/1282c19:dd:d9:dd:c25:c25:d915:7fac
1742c19:dd:d9:dd:c25:c25:d915:7fad/1282c19:dd:d9:dd:c25:c25:d915:7fad
1752c19:dd:d9:dd:c25:c25:d915:7fae/1282c19:dd:d9:dd:c25:c25:d915:7fae
1762c19:dd:d9:dd:c25:c25:d915:7faf/1282c19:dd:d9:dd:c25:c25:d915:7faf
1772c19:dd:d9:dd:c25:c25:d915:7fb0/1282c19:dd:d9:dd:c25:c25:d915:7fb0
1782c19:dd:d9:dd:c25:c25:d915:7fb1/1282c19:dd:d9:dd:c25:c25:d915:7fb1
1792c19:dd:d9:dd:c25:c25:d915:7fb2/1282c19:dd:d9:dd:c25:c25:d915:7fb2
1802c19:dd:d9:dd:c25:c25:d915:7fb3/1282c19:dd:d9:dd:c25:c25:d915:7fb3
1812c19:dd:d9:dd:c25:c25:d915:7fb4/1282c19:dd:d9:dd:c25:c25:d915:7fb4
1822c19:dd:d9:dd:c25:c25:d915:7fb5/1282c19:dd:d9:dd:c25:c25:d915:7fb5
1832c19:dd:d9:dd:c25:c25:d915:7fb6/1282c19:dd:d9:dd:c25:c25:d915:7fb6
1842c19:dd:d9:dd:c25:c25:d915:7fb7/1282c19:dd:d9:dd:c25:c25:d915:7fb7
1852c19:dd:d9:dd:c25:c25:d915:7fb8/1282c19:dd:d9:dd:c25:c25:d915:7fb8
1862c19:dd:d9:dd:c25:c25:d915:7fb9/1282c19:dd:d9:dd:c25:c25:d915:7fb9
1872c19:dd:d9:dd:c25:c25:d915:7fba/1282c19:dd:d9:dd:c25:c25:d915:7fba
1882c19:dd:d9:dd:c25:c25:d915:7fbb/1282c19:dd:d9:dd:c25:c25:d915:7fbb
1892c19:dd:d9:dd:c25:c25:d915:7fbc/1282c19:dd:d9:dd:c25:c25:d915:7fbc
1902c19:dd:d9:dd:c25:c25:d915:7fbd/1282c19:dd:d9:dd:c25:c25:d915:7fbd
1912c19:dd:d9:dd:c25:c25:d915:7fbe/1282c19:dd:d9:dd:c25:c25:d915:7fbe
1922c19:dd:d9:dd:c25:c25:d915:7fbf/1282c19:dd:d9:dd:c25:c25:d915:7fbf
1932c19:dd:d9:dd:c25:c25:d915:7fc0/1282c19:dd:d9:dd:c25:c25:d915:7fc0
1942c19:dd:d9:dd:c25:c25:d915:7fc1/1282c19:dd:d9:dd:c25:c25:d915:7fc1
1952c19:dd:d9:dd:c25:c25:d915:7fc2/1282c19:dd:d9:dd:c25:c25:d915:7fc2
1962c19:dd:d9:dd:c25:c25:d915:7fc3/1282c19:dd:d9:dd:c25:c25:d915:7fc3
1972c19:dd:d9:dd:c25:c25:d915:7fc4/1282c19:dd:d9:dd:c25:c25:d915:7fc4
1982c19:dd:d9:dd:c25:c25:d915:7fc5/1282c19:dd:d9:dd:c25:c25:d915:7fc5
1992c19:dd:d9:dd:c25:c25:d915:7fc6/1282c19:dd:d9:dd:c25:c25:d915:7fc6
2002c19:dd:d9:dd:c25:c25:d915:7fc7/1282c19:dd:d9:dd:c25:c25:d915:7fc7
2012c19:dd:d9:dd:c25:c25:d915:7fc8/1282c19:dd:d9:dd:c25:c25:d915:7fc8
2022c19:dd:d9:dd:c25:c25:d915:7fc9/1282c19:dd:d9:dd:c25:c25:d915:7fc9
2032c19:dd:d9:dd:c25:c25:d915:7fca/1282c19:dd:d9:dd:c25:c25:d915:7fca
2042c19:dd:d9:dd:c25:c25:d915:7fcb/1282c19:dd:d9:dd:c25:c25:d915:7fcb
2052c19:dd:d9:dd:c25:c25:d915:7fcc/1282c19:dd:d9:dd:c25:c25:d915:7fcc
2062c19:dd:d9:dd:c25:c25:d915:7fcd/1282c19:dd:d9:dd:c25:c25:d915:7fcd
2072c19:dd:d9:dd:c25:c25:d915:7fce/1282c19:dd:d9:dd:c25:c25:d915:7fce
2082c19:dd:d9:dd:c25:c25:d915:7fcf/1282c19:dd:d9:dd:c25:c25:d915:7fcf
2092c19:dd:d9:dd:c25:c25:d915:7fd0/1282c19:dd:d9:dd:c25:c25:d915:7fd0
2102c19:dd:d9:dd:c25:c25:d915:7fd1/1282c19:dd:d9:dd:c25:c25:d915:7fd1
2112c19:dd:d9:dd:c25:c25:d915:7fd2/1282c19:dd:d9:dd:c25:c25:d915:7fd2
2122c19:dd:d9:dd:c25:c25:d915:7fd3/1282c19:dd:d9:dd:c25:c25:d915:7fd3
2132c19:dd:d9:dd:c25:c25:d915:7fd4/1282c19:dd:d9:dd:c25:c25:d915:7fd4
2142c19:dd:d9:dd:c25:c25:d915:7fd5/1282c19:dd:d9:dd:c25:c25:d915:7fd5
2152c19:dd:d9:dd:c25:c25:d915:7fd6/1282c19:dd:d9:dd:c25:c25:d915:7fd6
2162c19:dd:d9:dd:c25:c25:d915:7fd7/1282c19:dd:d9:dd:c25:c25:d915:7fd7
2172c19:dd:d9:dd:c25:c25:d915:7fd8/1282c19:dd:d9:dd:c25:c25:d915:7fd8
2182c19:dd:d9:dd:c25:c25:d915:7fd9/1282c19:dd:d9:dd:c25:c25:d915:7fd9
2192c19:dd:d9:dd:c25:c25:d915:7fda/1282c19:dd:d9:dd:c25:c25:d915:7fda
2202c19:dd:d9:dd:c25:c25:d915:7fdb/1282c19:dd:d9:dd:c25:c25:d915:7fdb
2212c19:dd:d9:dd:c25:c25:d915:7fdc/1282c19:dd:d9:dd:c25:c25:d915:7fdc
2222c19:dd:d9:dd:c25:c25:d915:7fdd/1282c19:dd:d9:dd:c25:c25:d915:7fdd
2232c19:dd:d9:dd:c25:c25:d915:7fde/1282c19:dd:d9:dd:c25:c25:d915:7fde
2242c19:dd:d9:dd:c25:c25:d915:7fdf/1282c19:dd:d9:dd:c25:c25:d915:7fdf
2252c19:dd:d9:dd:c25:c25:d915:7fe0/1282c19:dd:d9:dd:c25:c25:d915:7fe0
2262c19:dd:d9:dd:c25:c25:d915:7fe1/1282c19:dd:d9:dd:c25:c25:d915:7fe1
2272c19:dd:d9:dd:c25:c25:d915:7fe2/1282c19:dd:d9:dd:c25:c25:d915:7fe2
2282c19:dd:d9:dd:c25:c25:d915:7fe3/1282c19:dd:d9:dd:c25:c25:d915:7fe3
2292c19:dd:d9:dd:c25:c25:d915:7fe4/1282c19:dd:d9:dd:c25:c25:d915:7fe4
2302c19:dd:d9:dd:c25:c25:d915:7fe5/1282c19:dd:d9:dd:c25:c25:d915:7fe5
2312c19:dd:d9:dd:c25:c25:d915:7fe6/1282c19:dd:d9:dd:c25:c25:d915:7fe6
2322c19:dd:d9:dd:c25:c25:d915:7fe7/1282c19:dd:d9:dd:c25:c25:d915:7fe7
2332c19:dd:d9:dd:c25:c25:d915:7fe8/1282c19:dd:d9:dd:c25:c25:d915:7fe8
2342c19:dd:d9:dd:c25:c25:d915:7fe9/1282c19:dd:d9:dd:c25:c25:d915:7fe9
2352c19:dd:d9:dd:c25:c25:d915:7fea/1282c19:dd:d9:dd:c25:c25:d915:7fea
2362c19:dd:d9:dd:c25:c25:d915:7feb/1282c19:dd:d9:dd:c25:c25:d915:7feb
2372c19:dd:d9:dd:c25:c25:d915:7fec/1282c19:dd:d9:dd:c25:c25:d915:7fec
2382c19:dd:d9:dd:c25:c25:d915:7fed/1282c19:dd:d9:dd:c25:c25:d915:7fed
2392c19:dd:d9:dd:c25:c25:d915:7fee/1282c19:dd:d9:dd:c25:c25:d915:7fee
2402c19:dd:d9:dd:c25:c25:d915:7fef/1282c19:dd:d9:dd:c25:c25:d915:7fef
2412c19:dd:d9:dd:c25:c25:d915:7ff0/1282c19:dd:d9:dd:c25:c25:d915:7ff0
2422c19:dd:d9:dd:c25:c25:d915:7ff1/1282c19:dd:d9:dd:c25:c25:d915:7ff1
2432c19:dd:d9:dd:c25:c25:d915:7ff2/1282c19:dd:d9:dd:c25:c25:d915:7ff2
2442c19:dd:d9:dd:c25:c25:d915:7ff3/1282c19:dd:d9:dd:c25:c25:d915:7ff3
2452c19:dd:d9:dd:c25:c25:d915:7ff4/1282c19:dd:d9:dd:c25:c25:d915:7ff4
2462c19:dd:d9:dd:c25:c25:d915:7ff5/1282c19:dd:d9:dd:c25:c25:d915:7ff5
2472c19:dd:d9:dd:c25:c25:d915:7ff6/1282c19:dd:d9:dd:c25:c25:d915:7ff6
2482c19:dd:d9:dd:c25:c25:d915:7ff7/1282c19:dd:d9:dd:c25:c25:d915:7ff7
2492c19:dd:d9:dd:c25:c25:d915:7ff8/1282c19:dd:d9:dd:c25:c25:d915:7ff8
2502c19:dd:d9:dd:c25:c25:d915:7ff9/1282c19:dd:d9:dd:c25:c25:d915:7ff9
2512c19:dd:d9:dd:c25:c25:d915:7ffa/1282c19:dd:d9:dd:c25:c25:d915:7ffa
2522c19:dd:d9:dd:c25:c25:d915:7ffb/1282c19:dd:d9:dd:c25:c25:d915:7ffb
2532c19:dd:d9:dd:c25:c25:d915:7ffc/1282c19:dd:d9:dd:c25:c25:d915:7ffc
2542c19:dd:d9:dd:c25:c25:d915:7ffd/1282c19:dd:d9:dd:c25:c25:d915:7ffd
2552c19:dd:d9:dd:c25:c25:d915:7ffe/1282c19:dd:d9:dd:c25:c25:d915:7ffe
2562c19:dd:d9:dd:c25:c25:d915:7fff/1282c19:dd:d9:dd:c25:c25:d915:7fff

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.