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

2c19:dd:d9:dd:c25:c25:94de:4f00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:4f00/1282c19:dd:d9:dd:c25:c25:94de:4f00
22c19:dd:d9:dd:c25:c25:94de:4f01/1282c19:dd:d9:dd:c25:c25:94de:4f01
32c19:dd:d9:dd:c25:c25:94de:4f02/1282c19:dd:d9:dd:c25:c25:94de:4f02
42c19:dd:d9:dd:c25:c25:94de:4f03/1282c19:dd:d9:dd:c25:c25:94de:4f03
52c19:dd:d9:dd:c25:c25:94de:4f04/1282c19:dd:d9:dd:c25:c25:94de:4f04
62c19:dd:d9:dd:c25:c25:94de:4f05/1282c19:dd:d9:dd:c25:c25:94de:4f05
72c19:dd:d9:dd:c25:c25:94de:4f06/1282c19:dd:d9:dd:c25:c25:94de:4f06
82c19:dd:d9:dd:c25:c25:94de:4f07/1282c19:dd:d9:dd:c25:c25:94de:4f07
92c19:dd:d9:dd:c25:c25:94de:4f08/1282c19:dd:d9:dd:c25:c25:94de:4f08
102c19:dd:d9:dd:c25:c25:94de:4f09/1282c19:dd:d9:dd:c25:c25:94de:4f09
112c19:dd:d9:dd:c25:c25:94de:4f0a/1282c19:dd:d9:dd:c25:c25:94de:4f0a
122c19:dd:d9:dd:c25:c25:94de:4f0b/1282c19:dd:d9:dd:c25:c25:94de:4f0b
132c19:dd:d9:dd:c25:c25:94de:4f0c/1282c19:dd:d9:dd:c25:c25:94de:4f0c
142c19:dd:d9:dd:c25:c25:94de:4f0d/1282c19:dd:d9:dd:c25:c25:94de:4f0d
152c19:dd:d9:dd:c25:c25:94de:4f0e/1282c19:dd:d9:dd:c25:c25:94de:4f0e
162c19:dd:d9:dd:c25:c25:94de:4f0f/1282c19:dd:d9:dd:c25:c25:94de:4f0f
172c19:dd:d9:dd:c25:c25:94de:4f10/1282c19:dd:d9:dd:c25:c25:94de:4f10
182c19:dd:d9:dd:c25:c25:94de:4f11/1282c19:dd:d9:dd:c25:c25:94de:4f11
192c19:dd:d9:dd:c25:c25:94de:4f12/1282c19:dd:d9:dd:c25:c25:94de:4f12
202c19:dd:d9:dd:c25:c25:94de:4f13/1282c19:dd:d9:dd:c25:c25:94de:4f13
212c19:dd:d9:dd:c25:c25:94de:4f14/1282c19:dd:d9:dd:c25:c25:94de:4f14
222c19:dd:d9:dd:c25:c25:94de:4f15/1282c19:dd:d9:dd:c25:c25:94de:4f15
232c19:dd:d9:dd:c25:c25:94de:4f16/1282c19:dd:d9:dd:c25:c25:94de:4f16
242c19:dd:d9:dd:c25:c25:94de:4f17/1282c19:dd:d9:dd:c25:c25:94de:4f17
252c19:dd:d9:dd:c25:c25:94de:4f18/1282c19:dd:d9:dd:c25:c25:94de:4f18
262c19:dd:d9:dd:c25:c25:94de:4f19/1282c19:dd:d9:dd:c25:c25:94de:4f19
272c19:dd:d9:dd:c25:c25:94de:4f1a/1282c19:dd:d9:dd:c25:c25:94de:4f1a
282c19:dd:d9:dd:c25:c25:94de:4f1b/1282c19:dd:d9:dd:c25:c25:94de:4f1b
292c19:dd:d9:dd:c25:c25:94de:4f1c/1282c19:dd:d9:dd:c25:c25:94de:4f1c
302c19:dd:d9:dd:c25:c25:94de:4f1d/1282c19:dd:d9:dd:c25:c25:94de:4f1d
312c19:dd:d9:dd:c25:c25:94de:4f1e/1282c19:dd:d9:dd:c25:c25:94de:4f1e
322c19:dd:d9:dd:c25:c25:94de:4f1f/1282c19:dd:d9:dd:c25:c25:94de:4f1f
332c19:dd:d9:dd:c25:c25:94de:4f20/1282c19:dd:d9:dd:c25:c25:94de:4f20
342c19:dd:d9:dd:c25:c25:94de:4f21/1282c19:dd:d9:dd:c25:c25:94de:4f21
352c19:dd:d9:dd:c25:c25:94de:4f22/1282c19:dd:d9:dd:c25:c25:94de:4f22
362c19:dd:d9:dd:c25:c25:94de:4f23/1282c19:dd:d9:dd:c25:c25:94de:4f23
372c19:dd:d9:dd:c25:c25:94de:4f24/1282c19:dd:d9:dd:c25:c25:94de:4f24
382c19:dd:d9:dd:c25:c25:94de:4f25/1282c19:dd:d9:dd:c25:c25:94de:4f25
392c19:dd:d9:dd:c25:c25:94de:4f26/1282c19:dd:d9:dd:c25:c25:94de:4f26
402c19:dd:d9:dd:c25:c25:94de:4f27/1282c19:dd:d9:dd:c25:c25:94de:4f27
412c19:dd:d9:dd:c25:c25:94de:4f28/1282c19:dd:d9:dd:c25:c25:94de:4f28
422c19:dd:d9:dd:c25:c25:94de:4f29/1282c19:dd:d9:dd:c25:c25:94de:4f29
432c19:dd:d9:dd:c25:c25:94de:4f2a/1282c19:dd:d9:dd:c25:c25:94de:4f2a
442c19:dd:d9:dd:c25:c25:94de:4f2b/1282c19:dd:d9:dd:c25:c25:94de:4f2b
452c19:dd:d9:dd:c25:c25:94de:4f2c/1282c19:dd:d9:dd:c25:c25:94de:4f2c
462c19:dd:d9:dd:c25:c25:94de:4f2d/1282c19:dd:d9:dd:c25:c25:94de:4f2d
472c19:dd:d9:dd:c25:c25:94de:4f2e/1282c19:dd:d9:dd:c25:c25:94de:4f2e
482c19:dd:d9:dd:c25:c25:94de:4f2f/1282c19:dd:d9:dd:c25:c25:94de:4f2f
492c19:dd:d9:dd:c25:c25:94de:4f30/1282c19:dd:d9:dd:c25:c25:94de:4f30
502c19:dd:d9:dd:c25:c25:94de:4f31/1282c19:dd:d9:dd:c25:c25:94de:4f31
512c19:dd:d9:dd:c25:c25:94de:4f32/1282c19:dd:d9:dd:c25:c25:94de:4f32
522c19:dd:d9:dd:c25:c25:94de:4f33/1282c19:dd:d9:dd:c25:c25:94de:4f33
532c19:dd:d9:dd:c25:c25:94de:4f34/1282c19:dd:d9:dd:c25:c25:94de:4f34
542c19:dd:d9:dd:c25:c25:94de:4f35/1282c19:dd:d9:dd:c25:c25:94de:4f35
552c19:dd:d9:dd:c25:c25:94de:4f36/1282c19:dd:d9:dd:c25:c25:94de:4f36
562c19:dd:d9:dd:c25:c25:94de:4f37/1282c19:dd:d9:dd:c25:c25:94de:4f37
572c19:dd:d9:dd:c25:c25:94de:4f38/1282c19:dd:d9:dd:c25:c25:94de:4f38
582c19:dd:d9:dd:c25:c25:94de:4f39/1282c19:dd:d9:dd:c25:c25:94de:4f39
592c19:dd:d9:dd:c25:c25:94de:4f3a/1282c19:dd:d9:dd:c25:c25:94de:4f3a
602c19:dd:d9:dd:c25:c25:94de:4f3b/1282c19:dd:d9:dd:c25:c25:94de:4f3b
612c19:dd:d9:dd:c25:c25:94de:4f3c/1282c19:dd:d9:dd:c25:c25:94de:4f3c
622c19:dd:d9:dd:c25:c25:94de:4f3d/1282c19:dd:d9:dd:c25:c25:94de:4f3d
632c19:dd:d9:dd:c25:c25:94de:4f3e/1282c19:dd:d9:dd:c25:c25:94de:4f3e
642c19:dd:d9:dd:c25:c25:94de:4f3f/1282c19:dd:d9:dd:c25:c25:94de:4f3f
652c19:dd:d9:dd:c25:c25:94de:4f40/1282c19:dd:d9:dd:c25:c25:94de:4f40
662c19:dd:d9:dd:c25:c25:94de:4f41/1282c19:dd:d9:dd:c25:c25:94de:4f41
672c19:dd:d9:dd:c25:c25:94de:4f42/1282c19:dd:d9:dd:c25:c25:94de:4f42
682c19:dd:d9:dd:c25:c25:94de:4f43/1282c19:dd:d9:dd:c25:c25:94de:4f43
692c19:dd:d9:dd:c25:c25:94de:4f44/1282c19:dd:d9:dd:c25:c25:94de:4f44
702c19:dd:d9:dd:c25:c25:94de:4f45/1282c19:dd:d9:dd:c25:c25:94de:4f45
712c19:dd:d9:dd:c25:c25:94de:4f46/1282c19:dd:d9:dd:c25:c25:94de:4f46
722c19:dd:d9:dd:c25:c25:94de:4f47/1282c19:dd:d9:dd:c25:c25:94de:4f47
732c19:dd:d9:dd:c25:c25:94de:4f48/1282c19:dd:d9:dd:c25:c25:94de:4f48
742c19:dd:d9:dd:c25:c25:94de:4f49/1282c19:dd:d9:dd:c25:c25:94de:4f49
752c19:dd:d9:dd:c25:c25:94de:4f4a/1282c19:dd:d9:dd:c25:c25:94de:4f4a
762c19:dd:d9:dd:c25:c25:94de:4f4b/1282c19:dd:d9:dd:c25:c25:94de:4f4b
772c19:dd:d9:dd:c25:c25:94de:4f4c/1282c19:dd:d9:dd:c25:c25:94de:4f4c
782c19:dd:d9:dd:c25:c25:94de:4f4d/1282c19:dd:d9:dd:c25:c25:94de:4f4d
792c19:dd:d9:dd:c25:c25:94de:4f4e/1282c19:dd:d9:dd:c25:c25:94de:4f4e
802c19:dd:d9:dd:c25:c25:94de:4f4f/1282c19:dd:d9:dd:c25:c25:94de:4f4f
812c19:dd:d9:dd:c25:c25:94de:4f50/1282c19:dd:d9:dd:c25:c25:94de:4f50
822c19:dd:d9:dd:c25:c25:94de:4f51/1282c19:dd:d9:dd:c25:c25:94de:4f51
832c19:dd:d9:dd:c25:c25:94de:4f52/1282c19:dd:d9:dd:c25:c25:94de:4f52
842c19:dd:d9:dd:c25:c25:94de:4f53/1282c19:dd:d9:dd:c25:c25:94de:4f53
852c19:dd:d9:dd:c25:c25:94de:4f54/1282c19:dd:d9:dd:c25:c25:94de:4f54
862c19:dd:d9:dd:c25:c25:94de:4f55/1282c19:dd:d9:dd:c25:c25:94de:4f55
872c19:dd:d9:dd:c25:c25:94de:4f56/1282c19:dd:d9:dd:c25:c25:94de:4f56
882c19:dd:d9:dd:c25:c25:94de:4f57/1282c19:dd:d9:dd:c25:c25:94de:4f57
892c19:dd:d9:dd:c25:c25:94de:4f58/1282c19:dd:d9:dd:c25:c25:94de:4f58
902c19:dd:d9:dd:c25:c25:94de:4f59/1282c19:dd:d9:dd:c25:c25:94de:4f59
912c19:dd:d9:dd:c25:c25:94de:4f5a/1282c19:dd:d9:dd:c25:c25:94de:4f5a
922c19:dd:d9:dd:c25:c25:94de:4f5b/1282c19:dd:d9:dd:c25:c25:94de:4f5b
932c19:dd:d9:dd:c25:c25:94de:4f5c/1282c19:dd:d9:dd:c25:c25:94de:4f5c
942c19:dd:d9:dd:c25:c25:94de:4f5d/1282c19:dd:d9:dd:c25:c25:94de:4f5d
952c19:dd:d9:dd:c25:c25:94de:4f5e/1282c19:dd:d9:dd:c25:c25:94de:4f5e
962c19:dd:d9:dd:c25:c25:94de:4f5f/1282c19:dd:d9:dd:c25:c25:94de:4f5f
972c19:dd:d9:dd:c25:c25:94de:4f60/1282c19:dd:d9:dd:c25:c25:94de:4f60
982c19:dd:d9:dd:c25:c25:94de:4f61/1282c19:dd:d9:dd:c25:c25:94de:4f61
992c19:dd:d9:dd:c25:c25:94de:4f62/1282c19:dd:d9:dd:c25:c25:94de:4f62
1002c19:dd:d9:dd:c25:c25:94de:4f63/1282c19:dd:d9:dd:c25:c25:94de:4f63
1012c19:dd:d9:dd:c25:c25:94de:4f64/1282c19:dd:d9:dd:c25:c25:94de:4f64
1022c19:dd:d9:dd:c25:c25:94de:4f65/1282c19:dd:d9:dd:c25:c25:94de:4f65
1032c19:dd:d9:dd:c25:c25:94de:4f66/1282c19:dd:d9:dd:c25:c25:94de:4f66
1042c19:dd:d9:dd:c25:c25:94de:4f67/1282c19:dd:d9:dd:c25:c25:94de:4f67
1052c19:dd:d9:dd:c25:c25:94de:4f68/1282c19:dd:d9:dd:c25:c25:94de:4f68
1062c19:dd:d9:dd:c25:c25:94de:4f69/1282c19:dd:d9:dd:c25:c25:94de:4f69
1072c19:dd:d9:dd:c25:c25:94de:4f6a/1282c19:dd:d9:dd:c25:c25:94de:4f6a
1082c19:dd:d9:dd:c25:c25:94de:4f6b/1282c19:dd:d9:dd:c25:c25:94de:4f6b
1092c19:dd:d9:dd:c25:c25:94de:4f6c/1282c19:dd:d9:dd:c25:c25:94de:4f6c
1102c19:dd:d9:dd:c25:c25:94de:4f6d/1282c19:dd:d9:dd:c25:c25:94de:4f6d
1112c19:dd:d9:dd:c25:c25:94de:4f6e/1282c19:dd:d9:dd:c25:c25:94de:4f6e
1122c19:dd:d9:dd:c25:c25:94de:4f6f/1282c19:dd:d9:dd:c25:c25:94de:4f6f
1132c19:dd:d9:dd:c25:c25:94de:4f70/1282c19:dd:d9:dd:c25:c25:94de:4f70
1142c19:dd:d9:dd:c25:c25:94de:4f71/1282c19:dd:d9:dd:c25:c25:94de:4f71
1152c19:dd:d9:dd:c25:c25:94de:4f72/1282c19:dd:d9:dd:c25:c25:94de:4f72
1162c19:dd:d9:dd:c25:c25:94de:4f73/1282c19:dd:d9:dd:c25:c25:94de:4f73
1172c19:dd:d9:dd:c25:c25:94de:4f74/1282c19:dd:d9:dd:c25:c25:94de:4f74
1182c19:dd:d9:dd:c25:c25:94de:4f75/1282c19:dd:d9:dd:c25:c25:94de:4f75
1192c19:dd:d9:dd:c25:c25:94de:4f76/1282c19:dd:d9:dd:c25:c25:94de:4f76
1202c19:dd:d9:dd:c25:c25:94de:4f77/1282c19:dd:d9:dd:c25:c25:94de:4f77
1212c19:dd:d9:dd:c25:c25:94de:4f78/1282c19:dd:d9:dd:c25:c25:94de:4f78
1222c19:dd:d9:dd:c25:c25:94de:4f79/1282c19:dd:d9:dd:c25:c25:94de:4f79
1232c19:dd:d9:dd:c25:c25:94de:4f7a/1282c19:dd:d9:dd:c25:c25:94de:4f7a
1242c19:dd:d9:dd:c25:c25:94de:4f7b/1282c19:dd:d9:dd:c25:c25:94de:4f7b
1252c19:dd:d9:dd:c25:c25:94de:4f7c/1282c19:dd:d9:dd:c25:c25:94de:4f7c
1262c19:dd:d9:dd:c25:c25:94de:4f7d/1282c19:dd:d9:dd:c25:c25:94de:4f7d
1272c19:dd:d9:dd:c25:c25:94de:4f7e/1282c19:dd:d9:dd:c25:c25:94de:4f7e
1282c19:dd:d9:dd:c25:c25:94de:4f7f/1282c19:dd:d9:dd:c25:c25:94de:4f7f
1292c19:dd:d9:dd:c25:c25:94de:4f80/1282c19:dd:d9:dd:c25:c25:94de:4f80
1302c19:dd:d9:dd:c25:c25:94de:4f81/1282c19:dd:d9:dd:c25:c25:94de:4f81
1312c19:dd:d9:dd:c25:c25:94de:4f82/1282c19:dd:d9:dd:c25:c25:94de:4f82
1322c19:dd:d9:dd:c25:c25:94de:4f83/1282c19:dd:d9:dd:c25:c25:94de:4f83
1332c19:dd:d9:dd:c25:c25:94de:4f84/1282c19:dd:d9:dd:c25:c25:94de:4f84
1342c19:dd:d9:dd:c25:c25:94de:4f85/1282c19:dd:d9:dd:c25:c25:94de:4f85
1352c19:dd:d9:dd:c25:c25:94de:4f86/1282c19:dd:d9:dd:c25:c25:94de:4f86
1362c19:dd:d9:dd:c25:c25:94de:4f87/1282c19:dd:d9:dd:c25:c25:94de:4f87
1372c19:dd:d9:dd:c25:c25:94de:4f88/1282c19:dd:d9:dd:c25:c25:94de:4f88
1382c19:dd:d9:dd:c25:c25:94de:4f89/1282c19:dd:d9:dd:c25:c25:94de:4f89
1392c19:dd:d9:dd:c25:c25:94de:4f8a/1282c19:dd:d9:dd:c25:c25:94de:4f8a
1402c19:dd:d9:dd:c25:c25:94de:4f8b/1282c19:dd:d9:dd:c25:c25:94de:4f8b
1412c19:dd:d9:dd:c25:c25:94de:4f8c/1282c19:dd:d9:dd:c25:c25:94de:4f8c
1422c19:dd:d9:dd:c25:c25:94de:4f8d/1282c19:dd:d9:dd:c25:c25:94de:4f8d
1432c19:dd:d9:dd:c25:c25:94de:4f8e/1282c19:dd:d9:dd:c25:c25:94de:4f8e
1442c19:dd:d9:dd:c25:c25:94de:4f8f/1282c19:dd:d9:dd:c25:c25:94de:4f8f
1452c19:dd:d9:dd:c25:c25:94de:4f90/1282c19:dd:d9:dd:c25:c25:94de:4f90
1462c19:dd:d9:dd:c25:c25:94de:4f91/1282c19:dd:d9:dd:c25:c25:94de:4f91
1472c19:dd:d9:dd:c25:c25:94de:4f92/1282c19:dd:d9:dd:c25:c25:94de:4f92
1482c19:dd:d9:dd:c25:c25:94de:4f93/1282c19:dd:d9:dd:c25:c25:94de:4f93
1492c19:dd:d9:dd:c25:c25:94de:4f94/1282c19:dd:d9:dd:c25:c25:94de:4f94
1502c19:dd:d9:dd:c25:c25:94de:4f95/1282c19:dd:d9:dd:c25:c25:94de:4f95
1512c19:dd:d9:dd:c25:c25:94de:4f96/1282c19:dd:d9:dd:c25:c25:94de:4f96
1522c19:dd:d9:dd:c25:c25:94de:4f97/1282c19:dd:d9:dd:c25:c25:94de:4f97
1532c19:dd:d9:dd:c25:c25:94de:4f98/1282c19:dd:d9:dd:c25:c25:94de:4f98
1542c19:dd:d9:dd:c25:c25:94de:4f99/1282c19:dd:d9:dd:c25:c25:94de:4f99
1552c19:dd:d9:dd:c25:c25:94de:4f9a/1282c19:dd:d9:dd:c25:c25:94de:4f9a
1562c19:dd:d9:dd:c25:c25:94de:4f9b/1282c19:dd:d9:dd:c25:c25:94de:4f9b
1572c19:dd:d9:dd:c25:c25:94de:4f9c/1282c19:dd:d9:dd:c25:c25:94de:4f9c
1582c19:dd:d9:dd:c25:c25:94de:4f9d/1282c19:dd:d9:dd:c25:c25:94de:4f9d
1592c19:dd:d9:dd:c25:c25:94de:4f9e/1282c19:dd:d9:dd:c25:c25:94de:4f9e
1602c19:dd:d9:dd:c25:c25:94de:4f9f/1282c19:dd:d9:dd:c25:c25:94de:4f9f
1612c19:dd:d9:dd:c25:c25:94de:4fa0/1282c19:dd:d9:dd:c25:c25:94de:4fa0
1622c19:dd:d9:dd:c25:c25:94de:4fa1/1282c19:dd:d9:dd:c25:c25:94de:4fa1
1632c19:dd:d9:dd:c25:c25:94de:4fa2/1282c19:dd:d9:dd:c25:c25:94de:4fa2
1642c19:dd:d9:dd:c25:c25:94de:4fa3/1282c19:dd:d9:dd:c25:c25:94de:4fa3
1652c19:dd:d9:dd:c25:c25:94de:4fa4/1282c19:dd:d9:dd:c25:c25:94de:4fa4
1662c19:dd:d9:dd:c25:c25:94de:4fa5/1282c19:dd:d9:dd:c25:c25:94de:4fa5
1672c19:dd:d9:dd:c25:c25:94de:4fa6/1282c19:dd:d9:dd:c25:c25:94de:4fa6
1682c19:dd:d9:dd:c25:c25:94de:4fa7/1282c19:dd:d9:dd:c25:c25:94de:4fa7
1692c19:dd:d9:dd:c25:c25:94de:4fa8/1282c19:dd:d9:dd:c25:c25:94de:4fa8
1702c19:dd:d9:dd:c25:c25:94de:4fa9/1282c19:dd:d9:dd:c25:c25:94de:4fa9
1712c19:dd:d9:dd:c25:c25:94de:4faa/1282c19:dd:d9:dd:c25:c25:94de:4faa
1722c19:dd:d9:dd:c25:c25:94de:4fab/1282c19:dd:d9:dd:c25:c25:94de:4fab
1732c19:dd:d9:dd:c25:c25:94de:4fac/1282c19:dd:d9:dd:c25:c25:94de:4fac
1742c19:dd:d9:dd:c25:c25:94de:4fad/1282c19:dd:d9:dd:c25:c25:94de:4fad
1752c19:dd:d9:dd:c25:c25:94de:4fae/1282c19:dd:d9:dd:c25:c25:94de:4fae
1762c19:dd:d9:dd:c25:c25:94de:4faf/1282c19:dd:d9:dd:c25:c25:94de:4faf
1772c19:dd:d9:dd:c25:c25:94de:4fb0/1282c19:dd:d9:dd:c25:c25:94de:4fb0
1782c19:dd:d9:dd:c25:c25:94de:4fb1/1282c19:dd:d9:dd:c25:c25:94de:4fb1
1792c19:dd:d9:dd:c25:c25:94de:4fb2/1282c19:dd:d9:dd:c25:c25:94de:4fb2
1802c19:dd:d9:dd:c25:c25:94de:4fb3/1282c19:dd:d9:dd:c25:c25:94de:4fb3
1812c19:dd:d9:dd:c25:c25:94de:4fb4/1282c19:dd:d9:dd:c25:c25:94de:4fb4
1822c19:dd:d9:dd:c25:c25:94de:4fb5/1282c19:dd:d9:dd:c25:c25:94de:4fb5
1832c19:dd:d9:dd:c25:c25:94de:4fb6/1282c19:dd:d9:dd:c25:c25:94de:4fb6
1842c19:dd:d9:dd:c25:c25:94de:4fb7/1282c19:dd:d9:dd:c25:c25:94de:4fb7
1852c19:dd:d9:dd:c25:c25:94de:4fb8/1282c19:dd:d9:dd:c25:c25:94de:4fb8
1862c19:dd:d9:dd:c25:c25:94de:4fb9/1282c19:dd:d9:dd:c25:c25:94de:4fb9
1872c19:dd:d9:dd:c25:c25:94de:4fba/1282c19:dd:d9:dd:c25:c25:94de:4fba
1882c19:dd:d9:dd:c25:c25:94de:4fbb/1282c19:dd:d9:dd:c25:c25:94de:4fbb
1892c19:dd:d9:dd:c25:c25:94de:4fbc/1282c19:dd:d9:dd:c25:c25:94de:4fbc
1902c19:dd:d9:dd:c25:c25:94de:4fbd/1282c19:dd:d9:dd:c25:c25:94de:4fbd
1912c19:dd:d9:dd:c25:c25:94de:4fbe/1282c19:dd:d9:dd:c25:c25:94de:4fbe
1922c19:dd:d9:dd:c25:c25:94de:4fbf/1282c19:dd:d9:dd:c25:c25:94de:4fbf
1932c19:dd:d9:dd:c25:c25:94de:4fc0/1282c19:dd:d9:dd:c25:c25:94de:4fc0
1942c19:dd:d9:dd:c25:c25:94de:4fc1/1282c19:dd:d9:dd:c25:c25:94de:4fc1
1952c19:dd:d9:dd:c25:c25:94de:4fc2/1282c19:dd:d9:dd:c25:c25:94de:4fc2
1962c19:dd:d9:dd:c25:c25:94de:4fc3/1282c19:dd:d9:dd:c25:c25:94de:4fc3
1972c19:dd:d9:dd:c25:c25:94de:4fc4/1282c19:dd:d9:dd:c25:c25:94de:4fc4
1982c19:dd:d9:dd:c25:c25:94de:4fc5/1282c19:dd:d9:dd:c25:c25:94de:4fc5
1992c19:dd:d9:dd:c25:c25:94de:4fc6/1282c19:dd:d9:dd:c25:c25:94de:4fc6
2002c19:dd:d9:dd:c25:c25:94de:4fc7/1282c19:dd:d9:dd:c25:c25:94de:4fc7
2012c19:dd:d9:dd:c25:c25:94de:4fc8/1282c19:dd:d9:dd:c25:c25:94de:4fc8
2022c19:dd:d9:dd:c25:c25:94de:4fc9/1282c19:dd:d9:dd:c25:c25:94de:4fc9
2032c19:dd:d9:dd:c25:c25:94de:4fca/1282c19:dd:d9:dd:c25:c25:94de:4fca
2042c19:dd:d9:dd:c25:c25:94de:4fcb/1282c19:dd:d9:dd:c25:c25:94de:4fcb
2052c19:dd:d9:dd:c25:c25:94de:4fcc/1282c19:dd:d9:dd:c25:c25:94de:4fcc
2062c19:dd:d9:dd:c25:c25:94de:4fcd/1282c19:dd:d9:dd:c25:c25:94de:4fcd
2072c19:dd:d9:dd:c25:c25:94de:4fce/1282c19:dd:d9:dd:c25:c25:94de:4fce
2082c19:dd:d9:dd:c25:c25:94de:4fcf/1282c19:dd:d9:dd:c25:c25:94de:4fcf
2092c19:dd:d9:dd:c25:c25:94de:4fd0/1282c19:dd:d9:dd:c25:c25:94de:4fd0
2102c19:dd:d9:dd:c25:c25:94de:4fd1/1282c19:dd:d9:dd:c25:c25:94de:4fd1
2112c19:dd:d9:dd:c25:c25:94de:4fd2/1282c19:dd:d9:dd:c25:c25:94de:4fd2
2122c19:dd:d9:dd:c25:c25:94de:4fd3/1282c19:dd:d9:dd:c25:c25:94de:4fd3
2132c19:dd:d9:dd:c25:c25:94de:4fd4/1282c19:dd:d9:dd:c25:c25:94de:4fd4
2142c19:dd:d9:dd:c25:c25:94de:4fd5/1282c19:dd:d9:dd:c25:c25:94de:4fd5
2152c19:dd:d9:dd:c25:c25:94de:4fd6/1282c19:dd:d9:dd:c25:c25:94de:4fd6
2162c19:dd:d9:dd:c25:c25:94de:4fd7/1282c19:dd:d9:dd:c25:c25:94de:4fd7
2172c19:dd:d9:dd:c25:c25:94de:4fd8/1282c19:dd:d9:dd:c25:c25:94de:4fd8
2182c19:dd:d9:dd:c25:c25:94de:4fd9/1282c19:dd:d9:dd:c25:c25:94de:4fd9
2192c19:dd:d9:dd:c25:c25:94de:4fda/1282c19:dd:d9:dd:c25:c25:94de:4fda
2202c19:dd:d9:dd:c25:c25:94de:4fdb/1282c19:dd:d9:dd:c25:c25:94de:4fdb
2212c19:dd:d9:dd:c25:c25:94de:4fdc/1282c19:dd:d9:dd:c25:c25:94de:4fdc
2222c19:dd:d9:dd:c25:c25:94de:4fdd/1282c19:dd:d9:dd:c25:c25:94de:4fdd
2232c19:dd:d9:dd:c25:c25:94de:4fde/1282c19:dd:d9:dd:c25:c25:94de:4fde
2242c19:dd:d9:dd:c25:c25:94de:4fdf/1282c19:dd:d9:dd:c25:c25:94de:4fdf
2252c19:dd:d9:dd:c25:c25:94de:4fe0/1282c19:dd:d9:dd:c25:c25:94de:4fe0
2262c19:dd:d9:dd:c25:c25:94de:4fe1/1282c19:dd:d9:dd:c25:c25:94de:4fe1
2272c19:dd:d9:dd:c25:c25:94de:4fe2/1282c19:dd:d9:dd:c25:c25:94de:4fe2
2282c19:dd:d9:dd:c25:c25:94de:4fe3/1282c19:dd:d9:dd:c25:c25:94de:4fe3
2292c19:dd:d9:dd:c25:c25:94de:4fe4/1282c19:dd:d9:dd:c25:c25:94de:4fe4
2302c19:dd:d9:dd:c25:c25:94de:4fe5/1282c19:dd:d9:dd:c25:c25:94de:4fe5
2312c19:dd:d9:dd:c25:c25:94de:4fe6/1282c19:dd:d9:dd:c25:c25:94de:4fe6
2322c19:dd:d9:dd:c25:c25:94de:4fe7/1282c19:dd:d9:dd:c25:c25:94de:4fe7
2332c19:dd:d9:dd:c25:c25:94de:4fe8/1282c19:dd:d9:dd:c25:c25:94de:4fe8
2342c19:dd:d9:dd:c25:c25:94de:4fe9/1282c19:dd:d9:dd:c25:c25:94de:4fe9
2352c19:dd:d9:dd:c25:c25:94de:4fea/1282c19:dd:d9:dd:c25:c25:94de:4fea
2362c19:dd:d9:dd:c25:c25:94de:4feb/1282c19:dd:d9:dd:c25:c25:94de:4feb
2372c19:dd:d9:dd:c25:c25:94de:4fec/1282c19:dd:d9:dd:c25:c25:94de:4fec
2382c19:dd:d9:dd:c25:c25:94de:4fed/1282c19:dd:d9:dd:c25:c25:94de:4fed
2392c19:dd:d9:dd:c25:c25:94de:4fee/1282c19:dd:d9:dd:c25:c25:94de:4fee
2402c19:dd:d9:dd:c25:c25:94de:4fef/1282c19:dd:d9:dd:c25:c25:94de:4fef
2412c19:dd:d9:dd:c25:c25:94de:4ff0/1282c19:dd:d9:dd:c25:c25:94de:4ff0
2422c19:dd:d9:dd:c25:c25:94de:4ff1/1282c19:dd:d9:dd:c25:c25:94de:4ff1
2432c19:dd:d9:dd:c25:c25:94de:4ff2/1282c19:dd:d9:dd:c25:c25:94de:4ff2
2442c19:dd:d9:dd:c25:c25:94de:4ff3/1282c19:dd:d9:dd:c25:c25:94de:4ff3
2452c19:dd:d9:dd:c25:c25:94de:4ff4/1282c19:dd:d9:dd:c25:c25:94de:4ff4
2462c19:dd:d9:dd:c25:c25:94de:4ff5/1282c19:dd:d9:dd:c25:c25:94de:4ff5
2472c19:dd:d9:dd:c25:c25:94de:4ff6/1282c19:dd:d9:dd:c25:c25:94de:4ff6
2482c19:dd:d9:dd:c25:c25:94de:4ff7/1282c19:dd:d9:dd:c25:c25:94de:4ff7
2492c19:dd:d9:dd:c25:c25:94de:4ff8/1282c19:dd:d9:dd:c25:c25:94de:4ff8
2502c19:dd:d9:dd:c25:c25:94de:4ff9/1282c19:dd:d9:dd:c25:c25:94de:4ff9
2512c19:dd:d9:dd:c25:c25:94de:4ffa/1282c19:dd:d9:dd:c25:c25:94de:4ffa
2522c19:dd:d9:dd:c25:c25:94de:4ffb/1282c19:dd:d9:dd:c25:c25:94de:4ffb
2532c19:dd:d9:dd:c25:c25:94de:4ffc/1282c19:dd:d9:dd:c25:c25:94de:4ffc
2542c19:dd:d9:dd:c25:c25:94de:4ffd/1282c19:dd:d9:dd:c25:c25:94de:4ffd
2552c19:dd:d9:dd:c25:c25:94de:4ffe/1282c19:dd:d9:dd:c25:c25:94de:4ffe
2562c19:dd:d9:dd:c25:c25:94de:4fff/1282c19: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.