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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:c25b:d00a:fb00/120
First address
2c19:dd:d9:dd:c25:c25b:d00a:fb00
Last address
2c19:dd:d9:dd:c25:c25b:d00a:fbff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25b:d00a:fb00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
b.f.a.0.0.d.b.5.2.c.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:c25b:d00a:fb00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25b:d00a:fb00/1282c19:dd:d9:dd:c25:c25b:d00a:fb00
22c19:dd:d9:dd:c25:c25b:d00a:fb01/1282c19:dd:d9:dd:c25:c25b:d00a:fb01
32c19:dd:d9:dd:c25:c25b:d00a:fb02/1282c19:dd:d9:dd:c25:c25b:d00a:fb02
42c19:dd:d9:dd:c25:c25b:d00a:fb03/1282c19:dd:d9:dd:c25:c25b:d00a:fb03
52c19:dd:d9:dd:c25:c25b:d00a:fb04/1282c19:dd:d9:dd:c25:c25b:d00a:fb04
62c19:dd:d9:dd:c25:c25b:d00a:fb05/1282c19:dd:d9:dd:c25:c25b:d00a:fb05
72c19:dd:d9:dd:c25:c25b:d00a:fb06/1282c19:dd:d9:dd:c25:c25b:d00a:fb06
82c19:dd:d9:dd:c25:c25b:d00a:fb07/1282c19:dd:d9:dd:c25:c25b:d00a:fb07
92c19:dd:d9:dd:c25:c25b:d00a:fb08/1282c19:dd:d9:dd:c25:c25b:d00a:fb08
102c19:dd:d9:dd:c25:c25b:d00a:fb09/1282c19:dd:d9:dd:c25:c25b:d00a:fb09
112c19:dd:d9:dd:c25:c25b:d00a:fb0a/1282c19:dd:d9:dd:c25:c25b:d00a:fb0a
122c19:dd:d9:dd:c25:c25b:d00a:fb0b/1282c19:dd:d9:dd:c25:c25b:d00a:fb0b
132c19:dd:d9:dd:c25:c25b:d00a:fb0c/1282c19:dd:d9:dd:c25:c25b:d00a:fb0c
142c19:dd:d9:dd:c25:c25b:d00a:fb0d/1282c19:dd:d9:dd:c25:c25b:d00a:fb0d
152c19:dd:d9:dd:c25:c25b:d00a:fb0e/1282c19:dd:d9:dd:c25:c25b:d00a:fb0e
162c19:dd:d9:dd:c25:c25b:d00a:fb0f/1282c19:dd:d9:dd:c25:c25b:d00a:fb0f
172c19:dd:d9:dd:c25:c25b:d00a:fb10/1282c19:dd:d9:dd:c25:c25b:d00a:fb10
182c19:dd:d9:dd:c25:c25b:d00a:fb11/1282c19:dd:d9:dd:c25:c25b:d00a:fb11
192c19:dd:d9:dd:c25:c25b:d00a:fb12/1282c19:dd:d9:dd:c25:c25b:d00a:fb12
202c19:dd:d9:dd:c25:c25b:d00a:fb13/1282c19:dd:d9:dd:c25:c25b:d00a:fb13
212c19:dd:d9:dd:c25:c25b:d00a:fb14/1282c19:dd:d9:dd:c25:c25b:d00a:fb14
222c19:dd:d9:dd:c25:c25b:d00a:fb15/1282c19:dd:d9:dd:c25:c25b:d00a:fb15
232c19:dd:d9:dd:c25:c25b:d00a:fb16/1282c19:dd:d9:dd:c25:c25b:d00a:fb16
242c19:dd:d9:dd:c25:c25b:d00a:fb17/1282c19:dd:d9:dd:c25:c25b:d00a:fb17
252c19:dd:d9:dd:c25:c25b:d00a:fb18/1282c19:dd:d9:dd:c25:c25b:d00a:fb18
262c19:dd:d9:dd:c25:c25b:d00a:fb19/1282c19:dd:d9:dd:c25:c25b:d00a:fb19
272c19:dd:d9:dd:c25:c25b:d00a:fb1a/1282c19:dd:d9:dd:c25:c25b:d00a:fb1a
282c19:dd:d9:dd:c25:c25b:d00a:fb1b/1282c19:dd:d9:dd:c25:c25b:d00a:fb1b
292c19:dd:d9:dd:c25:c25b:d00a:fb1c/1282c19:dd:d9:dd:c25:c25b:d00a:fb1c
302c19:dd:d9:dd:c25:c25b:d00a:fb1d/1282c19:dd:d9:dd:c25:c25b:d00a:fb1d
312c19:dd:d9:dd:c25:c25b:d00a:fb1e/1282c19:dd:d9:dd:c25:c25b:d00a:fb1e
322c19:dd:d9:dd:c25:c25b:d00a:fb1f/1282c19:dd:d9:dd:c25:c25b:d00a:fb1f
332c19:dd:d9:dd:c25:c25b:d00a:fb20/1282c19:dd:d9:dd:c25:c25b:d00a:fb20
342c19:dd:d9:dd:c25:c25b:d00a:fb21/1282c19:dd:d9:dd:c25:c25b:d00a:fb21
352c19:dd:d9:dd:c25:c25b:d00a:fb22/1282c19:dd:d9:dd:c25:c25b:d00a:fb22
362c19:dd:d9:dd:c25:c25b:d00a:fb23/1282c19:dd:d9:dd:c25:c25b:d00a:fb23
372c19:dd:d9:dd:c25:c25b:d00a:fb24/1282c19:dd:d9:dd:c25:c25b:d00a:fb24
382c19:dd:d9:dd:c25:c25b:d00a:fb25/1282c19:dd:d9:dd:c25:c25b:d00a:fb25
392c19:dd:d9:dd:c25:c25b:d00a:fb26/1282c19:dd:d9:dd:c25:c25b:d00a:fb26
402c19:dd:d9:dd:c25:c25b:d00a:fb27/1282c19:dd:d9:dd:c25:c25b:d00a:fb27
412c19:dd:d9:dd:c25:c25b:d00a:fb28/1282c19:dd:d9:dd:c25:c25b:d00a:fb28
422c19:dd:d9:dd:c25:c25b:d00a:fb29/1282c19:dd:d9:dd:c25:c25b:d00a:fb29
432c19:dd:d9:dd:c25:c25b:d00a:fb2a/1282c19:dd:d9:dd:c25:c25b:d00a:fb2a
442c19:dd:d9:dd:c25:c25b:d00a:fb2b/1282c19:dd:d9:dd:c25:c25b:d00a:fb2b
452c19:dd:d9:dd:c25:c25b:d00a:fb2c/1282c19:dd:d9:dd:c25:c25b:d00a:fb2c
462c19:dd:d9:dd:c25:c25b:d00a:fb2d/1282c19:dd:d9:dd:c25:c25b:d00a:fb2d
472c19:dd:d9:dd:c25:c25b:d00a:fb2e/1282c19:dd:d9:dd:c25:c25b:d00a:fb2e
482c19:dd:d9:dd:c25:c25b:d00a:fb2f/1282c19:dd:d9:dd:c25:c25b:d00a:fb2f
492c19:dd:d9:dd:c25:c25b:d00a:fb30/1282c19:dd:d9:dd:c25:c25b:d00a:fb30
502c19:dd:d9:dd:c25:c25b:d00a:fb31/1282c19:dd:d9:dd:c25:c25b:d00a:fb31
512c19:dd:d9:dd:c25:c25b:d00a:fb32/1282c19:dd:d9:dd:c25:c25b:d00a:fb32
522c19:dd:d9:dd:c25:c25b:d00a:fb33/1282c19:dd:d9:dd:c25:c25b:d00a:fb33
532c19:dd:d9:dd:c25:c25b:d00a:fb34/1282c19:dd:d9:dd:c25:c25b:d00a:fb34
542c19:dd:d9:dd:c25:c25b:d00a:fb35/1282c19:dd:d9:dd:c25:c25b:d00a:fb35
552c19:dd:d9:dd:c25:c25b:d00a:fb36/1282c19:dd:d9:dd:c25:c25b:d00a:fb36
562c19:dd:d9:dd:c25:c25b:d00a:fb37/1282c19:dd:d9:dd:c25:c25b:d00a:fb37
572c19:dd:d9:dd:c25:c25b:d00a:fb38/1282c19:dd:d9:dd:c25:c25b:d00a:fb38
582c19:dd:d9:dd:c25:c25b:d00a:fb39/1282c19:dd:d9:dd:c25:c25b:d00a:fb39
592c19:dd:d9:dd:c25:c25b:d00a:fb3a/1282c19:dd:d9:dd:c25:c25b:d00a:fb3a
602c19:dd:d9:dd:c25:c25b:d00a:fb3b/1282c19:dd:d9:dd:c25:c25b:d00a:fb3b
612c19:dd:d9:dd:c25:c25b:d00a:fb3c/1282c19:dd:d9:dd:c25:c25b:d00a:fb3c
622c19:dd:d9:dd:c25:c25b:d00a:fb3d/1282c19:dd:d9:dd:c25:c25b:d00a:fb3d
632c19:dd:d9:dd:c25:c25b:d00a:fb3e/1282c19:dd:d9:dd:c25:c25b:d00a:fb3e
642c19:dd:d9:dd:c25:c25b:d00a:fb3f/1282c19:dd:d9:dd:c25:c25b:d00a:fb3f
652c19:dd:d9:dd:c25:c25b:d00a:fb40/1282c19:dd:d9:dd:c25:c25b:d00a:fb40
662c19:dd:d9:dd:c25:c25b:d00a:fb41/1282c19:dd:d9:dd:c25:c25b:d00a:fb41
672c19:dd:d9:dd:c25:c25b:d00a:fb42/1282c19:dd:d9:dd:c25:c25b:d00a:fb42
682c19:dd:d9:dd:c25:c25b:d00a:fb43/1282c19:dd:d9:dd:c25:c25b:d00a:fb43
692c19:dd:d9:dd:c25:c25b:d00a:fb44/1282c19:dd:d9:dd:c25:c25b:d00a:fb44
702c19:dd:d9:dd:c25:c25b:d00a:fb45/1282c19:dd:d9:dd:c25:c25b:d00a:fb45
712c19:dd:d9:dd:c25:c25b:d00a:fb46/1282c19:dd:d9:dd:c25:c25b:d00a:fb46
722c19:dd:d9:dd:c25:c25b:d00a:fb47/1282c19:dd:d9:dd:c25:c25b:d00a:fb47
732c19:dd:d9:dd:c25:c25b:d00a:fb48/1282c19:dd:d9:dd:c25:c25b:d00a:fb48
742c19:dd:d9:dd:c25:c25b:d00a:fb49/1282c19:dd:d9:dd:c25:c25b:d00a:fb49
752c19:dd:d9:dd:c25:c25b:d00a:fb4a/1282c19:dd:d9:dd:c25:c25b:d00a:fb4a
762c19:dd:d9:dd:c25:c25b:d00a:fb4b/1282c19:dd:d9:dd:c25:c25b:d00a:fb4b
772c19:dd:d9:dd:c25:c25b:d00a:fb4c/1282c19:dd:d9:dd:c25:c25b:d00a:fb4c
782c19:dd:d9:dd:c25:c25b:d00a:fb4d/1282c19:dd:d9:dd:c25:c25b:d00a:fb4d
792c19:dd:d9:dd:c25:c25b:d00a:fb4e/1282c19:dd:d9:dd:c25:c25b:d00a:fb4e
802c19:dd:d9:dd:c25:c25b:d00a:fb4f/1282c19:dd:d9:dd:c25:c25b:d00a:fb4f
812c19:dd:d9:dd:c25:c25b:d00a:fb50/1282c19:dd:d9:dd:c25:c25b:d00a:fb50
822c19:dd:d9:dd:c25:c25b:d00a:fb51/1282c19:dd:d9:dd:c25:c25b:d00a:fb51
832c19:dd:d9:dd:c25:c25b:d00a:fb52/1282c19:dd:d9:dd:c25:c25b:d00a:fb52
842c19:dd:d9:dd:c25:c25b:d00a:fb53/1282c19:dd:d9:dd:c25:c25b:d00a:fb53
852c19:dd:d9:dd:c25:c25b:d00a:fb54/1282c19:dd:d9:dd:c25:c25b:d00a:fb54
862c19:dd:d9:dd:c25:c25b:d00a:fb55/1282c19:dd:d9:dd:c25:c25b:d00a:fb55
872c19:dd:d9:dd:c25:c25b:d00a:fb56/1282c19:dd:d9:dd:c25:c25b:d00a:fb56
882c19:dd:d9:dd:c25:c25b:d00a:fb57/1282c19:dd:d9:dd:c25:c25b:d00a:fb57
892c19:dd:d9:dd:c25:c25b:d00a:fb58/1282c19:dd:d9:dd:c25:c25b:d00a:fb58
902c19:dd:d9:dd:c25:c25b:d00a:fb59/1282c19:dd:d9:dd:c25:c25b:d00a:fb59
912c19:dd:d9:dd:c25:c25b:d00a:fb5a/1282c19:dd:d9:dd:c25:c25b:d00a:fb5a
922c19:dd:d9:dd:c25:c25b:d00a:fb5b/1282c19:dd:d9:dd:c25:c25b:d00a:fb5b
932c19:dd:d9:dd:c25:c25b:d00a:fb5c/1282c19:dd:d9:dd:c25:c25b:d00a:fb5c
942c19:dd:d9:dd:c25:c25b:d00a:fb5d/1282c19:dd:d9:dd:c25:c25b:d00a:fb5d
952c19:dd:d9:dd:c25:c25b:d00a:fb5e/1282c19:dd:d9:dd:c25:c25b:d00a:fb5e
962c19:dd:d9:dd:c25:c25b:d00a:fb5f/1282c19:dd:d9:dd:c25:c25b:d00a:fb5f
972c19:dd:d9:dd:c25:c25b:d00a:fb60/1282c19:dd:d9:dd:c25:c25b:d00a:fb60
982c19:dd:d9:dd:c25:c25b:d00a:fb61/1282c19:dd:d9:dd:c25:c25b:d00a:fb61
992c19:dd:d9:dd:c25:c25b:d00a:fb62/1282c19:dd:d9:dd:c25:c25b:d00a:fb62
1002c19:dd:d9:dd:c25:c25b:d00a:fb63/1282c19:dd:d9:dd:c25:c25b:d00a:fb63
1012c19:dd:d9:dd:c25:c25b:d00a:fb64/1282c19:dd:d9:dd:c25:c25b:d00a:fb64
1022c19:dd:d9:dd:c25:c25b:d00a:fb65/1282c19:dd:d9:dd:c25:c25b:d00a:fb65
1032c19:dd:d9:dd:c25:c25b:d00a:fb66/1282c19:dd:d9:dd:c25:c25b:d00a:fb66
1042c19:dd:d9:dd:c25:c25b:d00a:fb67/1282c19:dd:d9:dd:c25:c25b:d00a:fb67
1052c19:dd:d9:dd:c25:c25b:d00a:fb68/1282c19:dd:d9:dd:c25:c25b:d00a:fb68
1062c19:dd:d9:dd:c25:c25b:d00a:fb69/1282c19:dd:d9:dd:c25:c25b:d00a:fb69
1072c19:dd:d9:dd:c25:c25b:d00a:fb6a/1282c19:dd:d9:dd:c25:c25b:d00a:fb6a
1082c19:dd:d9:dd:c25:c25b:d00a:fb6b/1282c19:dd:d9:dd:c25:c25b:d00a:fb6b
1092c19:dd:d9:dd:c25:c25b:d00a:fb6c/1282c19:dd:d9:dd:c25:c25b:d00a:fb6c
1102c19:dd:d9:dd:c25:c25b:d00a:fb6d/1282c19:dd:d9:dd:c25:c25b:d00a:fb6d
1112c19:dd:d9:dd:c25:c25b:d00a:fb6e/1282c19:dd:d9:dd:c25:c25b:d00a:fb6e
1122c19:dd:d9:dd:c25:c25b:d00a:fb6f/1282c19:dd:d9:dd:c25:c25b:d00a:fb6f
1132c19:dd:d9:dd:c25:c25b:d00a:fb70/1282c19:dd:d9:dd:c25:c25b:d00a:fb70
1142c19:dd:d9:dd:c25:c25b:d00a:fb71/1282c19:dd:d9:dd:c25:c25b:d00a:fb71
1152c19:dd:d9:dd:c25:c25b:d00a:fb72/1282c19:dd:d9:dd:c25:c25b:d00a:fb72
1162c19:dd:d9:dd:c25:c25b:d00a:fb73/1282c19:dd:d9:dd:c25:c25b:d00a:fb73
1172c19:dd:d9:dd:c25:c25b:d00a:fb74/1282c19:dd:d9:dd:c25:c25b:d00a:fb74
1182c19:dd:d9:dd:c25:c25b:d00a:fb75/1282c19:dd:d9:dd:c25:c25b:d00a:fb75
1192c19:dd:d9:dd:c25:c25b:d00a:fb76/1282c19:dd:d9:dd:c25:c25b:d00a:fb76
1202c19:dd:d9:dd:c25:c25b:d00a:fb77/1282c19:dd:d9:dd:c25:c25b:d00a:fb77
1212c19:dd:d9:dd:c25:c25b:d00a:fb78/1282c19:dd:d9:dd:c25:c25b:d00a:fb78
1222c19:dd:d9:dd:c25:c25b:d00a:fb79/1282c19:dd:d9:dd:c25:c25b:d00a:fb79
1232c19:dd:d9:dd:c25:c25b:d00a:fb7a/1282c19:dd:d9:dd:c25:c25b:d00a:fb7a
1242c19:dd:d9:dd:c25:c25b:d00a:fb7b/1282c19:dd:d9:dd:c25:c25b:d00a:fb7b
1252c19:dd:d9:dd:c25:c25b:d00a:fb7c/1282c19:dd:d9:dd:c25:c25b:d00a:fb7c
1262c19:dd:d9:dd:c25:c25b:d00a:fb7d/1282c19:dd:d9:dd:c25:c25b:d00a:fb7d
1272c19:dd:d9:dd:c25:c25b:d00a:fb7e/1282c19:dd:d9:dd:c25:c25b:d00a:fb7e
1282c19:dd:d9:dd:c25:c25b:d00a:fb7f/1282c19:dd:d9:dd:c25:c25b:d00a:fb7f
1292c19:dd:d9:dd:c25:c25b:d00a:fb80/1282c19:dd:d9:dd:c25:c25b:d00a:fb80
1302c19:dd:d9:dd:c25:c25b:d00a:fb81/1282c19:dd:d9:dd:c25:c25b:d00a:fb81
1312c19:dd:d9:dd:c25:c25b:d00a:fb82/1282c19:dd:d9:dd:c25:c25b:d00a:fb82
1322c19:dd:d9:dd:c25:c25b:d00a:fb83/1282c19:dd:d9:dd:c25:c25b:d00a:fb83
1332c19:dd:d9:dd:c25:c25b:d00a:fb84/1282c19:dd:d9:dd:c25:c25b:d00a:fb84
1342c19:dd:d9:dd:c25:c25b:d00a:fb85/1282c19:dd:d9:dd:c25:c25b:d00a:fb85
1352c19:dd:d9:dd:c25:c25b:d00a:fb86/1282c19:dd:d9:dd:c25:c25b:d00a:fb86
1362c19:dd:d9:dd:c25:c25b:d00a:fb87/1282c19:dd:d9:dd:c25:c25b:d00a:fb87
1372c19:dd:d9:dd:c25:c25b:d00a:fb88/1282c19:dd:d9:dd:c25:c25b:d00a:fb88
1382c19:dd:d9:dd:c25:c25b:d00a:fb89/1282c19:dd:d9:dd:c25:c25b:d00a:fb89
1392c19:dd:d9:dd:c25:c25b:d00a:fb8a/1282c19:dd:d9:dd:c25:c25b:d00a:fb8a
1402c19:dd:d9:dd:c25:c25b:d00a:fb8b/1282c19:dd:d9:dd:c25:c25b:d00a:fb8b
1412c19:dd:d9:dd:c25:c25b:d00a:fb8c/1282c19:dd:d9:dd:c25:c25b:d00a:fb8c
1422c19:dd:d9:dd:c25:c25b:d00a:fb8d/1282c19:dd:d9:dd:c25:c25b:d00a:fb8d
1432c19:dd:d9:dd:c25:c25b:d00a:fb8e/1282c19:dd:d9:dd:c25:c25b:d00a:fb8e
1442c19:dd:d9:dd:c25:c25b:d00a:fb8f/1282c19:dd:d9:dd:c25:c25b:d00a:fb8f
1452c19:dd:d9:dd:c25:c25b:d00a:fb90/1282c19:dd:d9:dd:c25:c25b:d00a:fb90
1462c19:dd:d9:dd:c25:c25b:d00a:fb91/1282c19:dd:d9:dd:c25:c25b:d00a:fb91
1472c19:dd:d9:dd:c25:c25b:d00a:fb92/1282c19:dd:d9:dd:c25:c25b:d00a:fb92
1482c19:dd:d9:dd:c25:c25b:d00a:fb93/1282c19:dd:d9:dd:c25:c25b:d00a:fb93
1492c19:dd:d9:dd:c25:c25b:d00a:fb94/1282c19:dd:d9:dd:c25:c25b:d00a:fb94
1502c19:dd:d9:dd:c25:c25b:d00a:fb95/1282c19:dd:d9:dd:c25:c25b:d00a:fb95
1512c19:dd:d9:dd:c25:c25b:d00a:fb96/1282c19:dd:d9:dd:c25:c25b:d00a:fb96
1522c19:dd:d9:dd:c25:c25b:d00a:fb97/1282c19:dd:d9:dd:c25:c25b:d00a:fb97
1532c19:dd:d9:dd:c25:c25b:d00a:fb98/1282c19:dd:d9:dd:c25:c25b:d00a:fb98
1542c19:dd:d9:dd:c25:c25b:d00a:fb99/1282c19:dd:d9:dd:c25:c25b:d00a:fb99
1552c19:dd:d9:dd:c25:c25b:d00a:fb9a/1282c19:dd:d9:dd:c25:c25b:d00a:fb9a
1562c19:dd:d9:dd:c25:c25b:d00a:fb9b/1282c19:dd:d9:dd:c25:c25b:d00a:fb9b
1572c19:dd:d9:dd:c25:c25b:d00a:fb9c/1282c19:dd:d9:dd:c25:c25b:d00a:fb9c
1582c19:dd:d9:dd:c25:c25b:d00a:fb9d/1282c19:dd:d9:dd:c25:c25b:d00a:fb9d
1592c19:dd:d9:dd:c25:c25b:d00a:fb9e/1282c19:dd:d9:dd:c25:c25b:d00a:fb9e
1602c19:dd:d9:dd:c25:c25b:d00a:fb9f/1282c19:dd:d9:dd:c25:c25b:d00a:fb9f
1612c19:dd:d9:dd:c25:c25b:d00a:fba0/1282c19:dd:d9:dd:c25:c25b:d00a:fba0
1622c19:dd:d9:dd:c25:c25b:d00a:fba1/1282c19:dd:d9:dd:c25:c25b:d00a:fba1
1632c19:dd:d9:dd:c25:c25b:d00a:fba2/1282c19:dd:d9:dd:c25:c25b:d00a:fba2
1642c19:dd:d9:dd:c25:c25b:d00a:fba3/1282c19:dd:d9:dd:c25:c25b:d00a:fba3
1652c19:dd:d9:dd:c25:c25b:d00a:fba4/1282c19:dd:d9:dd:c25:c25b:d00a:fba4
1662c19:dd:d9:dd:c25:c25b:d00a:fba5/1282c19:dd:d9:dd:c25:c25b:d00a:fba5
1672c19:dd:d9:dd:c25:c25b:d00a:fba6/1282c19:dd:d9:dd:c25:c25b:d00a:fba6
1682c19:dd:d9:dd:c25:c25b:d00a:fba7/1282c19:dd:d9:dd:c25:c25b:d00a:fba7
1692c19:dd:d9:dd:c25:c25b:d00a:fba8/1282c19:dd:d9:dd:c25:c25b:d00a:fba8
1702c19:dd:d9:dd:c25:c25b:d00a:fba9/1282c19:dd:d9:dd:c25:c25b:d00a:fba9
1712c19:dd:d9:dd:c25:c25b:d00a:fbaa/1282c19:dd:d9:dd:c25:c25b:d00a:fbaa
1722c19:dd:d9:dd:c25:c25b:d00a:fbab/1282c19:dd:d9:dd:c25:c25b:d00a:fbab
1732c19:dd:d9:dd:c25:c25b:d00a:fbac/1282c19:dd:d9:dd:c25:c25b:d00a:fbac
1742c19:dd:d9:dd:c25:c25b:d00a:fbad/1282c19:dd:d9:dd:c25:c25b:d00a:fbad
1752c19:dd:d9:dd:c25:c25b:d00a:fbae/1282c19:dd:d9:dd:c25:c25b:d00a:fbae
1762c19:dd:d9:dd:c25:c25b:d00a:fbaf/1282c19:dd:d9:dd:c25:c25b:d00a:fbaf
1772c19:dd:d9:dd:c25:c25b:d00a:fbb0/1282c19:dd:d9:dd:c25:c25b:d00a:fbb0
1782c19:dd:d9:dd:c25:c25b:d00a:fbb1/1282c19:dd:d9:dd:c25:c25b:d00a:fbb1
1792c19:dd:d9:dd:c25:c25b:d00a:fbb2/1282c19:dd:d9:dd:c25:c25b:d00a:fbb2
1802c19:dd:d9:dd:c25:c25b:d00a:fbb3/1282c19:dd:d9:dd:c25:c25b:d00a:fbb3
1812c19:dd:d9:dd:c25:c25b:d00a:fbb4/1282c19:dd:d9:dd:c25:c25b:d00a:fbb4
1822c19:dd:d9:dd:c25:c25b:d00a:fbb5/1282c19:dd:d9:dd:c25:c25b:d00a:fbb5
1832c19:dd:d9:dd:c25:c25b:d00a:fbb6/1282c19:dd:d9:dd:c25:c25b:d00a:fbb6
1842c19:dd:d9:dd:c25:c25b:d00a:fbb7/1282c19:dd:d9:dd:c25:c25b:d00a:fbb7
1852c19:dd:d9:dd:c25:c25b:d00a:fbb8/1282c19:dd:d9:dd:c25:c25b:d00a:fbb8
1862c19:dd:d9:dd:c25:c25b:d00a:fbb9/1282c19:dd:d9:dd:c25:c25b:d00a:fbb9
1872c19:dd:d9:dd:c25:c25b:d00a:fbba/1282c19:dd:d9:dd:c25:c25b:d00a:fbba
1882c19:dd:d9:dd:c25:c25b:d00a:fbbb/1282c19:dd:d9:dd:c25:c25b:d00a:fbbb
1892c19:dd:d9:dd:c25:c25b:d00a:fbbc/1282c19:dd:d9:dd:c25:c25b:d00a:fbbc
1902c19:dd:d9:dd:c25:c25b:d00a:fbbd/1282c19:dd:d9:dd:c25:c25b:d00a:fbbd
1912c19:dd:d9:dd:c25:c25b:d00a:fbbe/1282c19:dd:d9:dd:c25:c25b:d00a:fbbe
1922c19:dd:d9:dd:c25:c25b:d00a:fbbf/1282c19:dd:d9:dd:c25:c25b:d00a:fbbf
1932c19:dd:d9:dd:c25:c25b:d00a:fbc0/1282c19:dd:d9:dd:c25:c25b:d00a:fbc0
1942c19:dd:d9:dd:c25:c25b:d00a:fbc1/1282c19:dd:d9:dd:c25:c25b:d00a:fbc1
1952c19:dd:d9:dd:c25:c25b:d00a:fbc2/1282c19:dd:d9:dd:c25:c25b:d00a:fbc2
1962c19:dd:d9:dd:c25:c25b:d00a:fbc3/1282c19:dd:d9:dd:c25:c25b:d00a:fbc3
1972c19:dd:d9:dd:c25:c25b:d00a:fbc4/1282c19:dd:d9:dd:c25:c25b:d00a:fbc4
1982c19:dd:d9:dd:c25:c25b:d00a:fbc5/1282c19:dd:d9:dd:c25:c25b:d00a:fbc5
1992c19:dd:d9:dd:c25:c25b:d00a:fbc6/1282c19:dd:d9:dd:c25:c25b:d00a:fbc6
2002c19:dd:d9:dd:c25:c25b:d00a:fbc7/1282c19:dd:d9:dd:c25:c25b:d00a:fbc7
2012c19:dd:d9:dd:c25:c25b:d00a:fbc8/1282c19:dd:d9:dd:c25:c25b:d00a:fbc8
2022c19:dd:d9:dd:c25:c25b:d00a:fbc9/1282c19:dd:d9:dd:c25:c25b:d00a:fbc9
2032c19:dd:d9:dd:c25:c25b:d00a:fbca/1282c19:dd:d9:dd:c25:c25b:d00a:fbca
2042c19:dd:d9:dd:c25:c25b:d00a:fbcb/1282c19:dd:d9:dd:c25:c25b:d00a:fbcb
2052c19:dd:d9:dd:c25:c25b:d00a:fbcc/1282c19:dd:d9:dd:c25:c25b:d00a:fbcc
2062c19:dd:d9:dd:c25:c25b:d00a:fbcd/1282c19:dd:d9:dd:c25:c25b:d00a:fbcd
2072c19:dd:d9:dd:c25:c25b:d00a:fbce/1282c19:dd:d9:dd:c25:c25b:d00a:fbce
2082c19:dd:d9:dd:c25:c25b:d00a:fbcf/1282c19:dd:d9:dd:c25:c25b:d00a:fbcf
2092c19:dd:d9:dd:c25:c25b:d00a:fbd0/1282c19:dd:d9:dd:c25:c25b:d00a:fbd0
2102c19:dd:d9:dd:c25:c25b:d00a:fbd1/1282c19:dd:d9:dd:c25:c25b:d00a:fbd1
2112c19:dd:d9:dd:c25:c25b:d00a:fbd2/1282c19:dd:d9:dd:c25:c25b:d00a:fbd2
2122c19:dd:d9:dd:c25:c25b:d00a:fbd3/1282c19:dd:d9:dd:c25:c25b:d00a:fbd3
2132c19:dd:d9:dd:c25:c25b:d00a:fbd4/1282c19:dd:d9:dd:c25:c25b:d00a:fbd4
2142c19:dd:d9:dd:c25:c25b:d00a:fbd5/1282c19:dd:d9:dd:c25:c25b:d00a:fbd5
2152c19:dd:d9:dd:c25:c25b:d00a:fbd6/1282c19:dd:d9:dd:c25:c25b:d00a:fbd6
2162c19:dd:d9:dd:c25:c25b:d00a:fbd7/1282c19:dd:d9:dd:c25:c25b:d00a:fbd7
2172c19:dd:d9:dd:c25:c25b:d00a:fbd8/1282c19:dd:d9:dd:c25:c25b:d00a:fbd8
2182c19:dd:d9:dd:c25:c25b:d00a:fbd9/1282c19:dd:d9:dd:c25:c25b:d00a:fbd9
2192c19:dd:d9:dd:c25:c25b:d00a:fbda/1282c19:dd:d9:dd:c25:c25b:d00a:fbda
2202c19:dd:d9:dd:c25:c25b:d00a:fbdb/1282c19:dd:d9:dd:c25:c25b:d00a:fbdb
2212c19:dd:d9:dd:c25:c25b:d00a:fbdc/1282c19:dd:d9:dd:c25:c25b:d00a:fbdc
2222c19:dd:d9:dd:c25:c25b:d00a:fbdd/1282c19:dd:d9:dd:c25:c25b:d00a:fbdd
2232c19:dd:d9:dd:c25:c25b:d00a:fbde/1282c19:dd:d9:dd:c25:c25b:d00a:fbde
2242c19:dd:d9:dd:c25:c25b:d00a:fbdf/1282c19:dd:d9:dd:c25:c25b:d00a:fbdf
2252c19:dd:d9:dd:c25:c25b:d00a:fbe0/1282c19:dd:d9:dd:c25:c25b:d00a:fbe0
2262c19:dd:d9:dd:c25:c25b:d00a:fbe1/1282c19:dd:d9:dd:c25:c25b:d00a:fbe1
2272c19:dd:d9:dd:c25:c25b:d00a:fbe2/1282c19:dd:d9:dd:c25:c25b:d00a:fbe2
2282c19:dd:d9:dd:c25:c25b:d00a:fbe3/1282c19:dd:d9:dd:c25:c25b:d00a:fbe3
2292c19:dd:d9:dd:c25:c25b:d00a:fbe4/1282c19:dd:d9:dd:c25:c25b:d00a:fbe4
2302c19:dd:d9:dd:c25:c25b:d00a:fbe5/1282c19:dd:d9:dd:c25:c25b:d00a:fbe5
2312c19:dd:d9:dd:c25:c25b:d00a:fbe6/1282c19:dd:d9:dd:c25:c25b:d00a:fbe6
2322c19:dd:d9:dd:c25:c25b:d00a:fbe7/1282c19:dd:d9:dd:c25:c25b:d00a:fbe7
2332c19:dd:d9:dd:c25:c25b:d00a:fbe8/1282c19:dd:d9:dd:c25:c25b:d00a:fbe8
2342c19:dd:d9:dd:c25:c25b:d00a:fbe9/1282c19:dd:d9:dd:c25:c25b:d00a:fbe9
2352c19:dd:d9:dd:c25:c25b:d00a:fbea/1282c19:dd:d9:dd:c25:c25b:d00a:fbea
2362c19:dd:d9:dd:c25:c25b:d00a:fbeb/1282c19:dd:d9:dd:c25:c25b:d00a:fbeb
2372c19:dd:d9:dd:c25:c25b:d00a:fbec/1282c19:dd:d9:dd:c25:c25b:d00a:fbec
2382c19:dd:d9:dd:c25:c25b:d00a:fbed/1282c19:dd:d9:dd:c25:c25b:d00a:fbed
2392c19:dd:d9:dd:c25:c25b:d00a:fbee/1282c19:dd:d9:dd:c25:c25b:d00a:fbee
2402c19:dd:d9:dd:c25:c25b:d00a:fbef/1282c19:dd:d9:dd:c25:c25b:d00a:fbef
2412c19:dd:d9:dd:c25:c25b:d00a:fbf0/1282c19:dd:d9:dd:c25:c25b:d00a:fbf0
2422c19:dd:d9:dd:c25:c25b:d00a:fbf1/1282c19:dd:d9:dd:c25:c25b:d00a:fbf1
2432c19:dd:d9:dd:c25:c25b:d00a:fbf2/1282c19:dd:d9:dd:c25:c25b:d00a:fbf2
2442c19:dd:d9:dd:c25:c25b:d00a:fbf3/1282c19:dd:d9:dd:c25:c25b:d00a:fbf3
2452c19:dd:d9:dd:c25:c25b:d00a:fbf4/1282c19:dd:d9:dd:c25:c25b:d00a:fbf4
2462c19:dd:d9:dd:c25:c25b:d00a:fbf5/1282c19:dd:d9:dd:c25:c25b:d00a:fbf5
2472c19:dd:d9:dd:c25:c25b:d00a:fbf6/1282c19:dd:d9:dd:c25:c25b:d00a:fbf6
2482c19:dd:d9:dd:c25:c25b:d00a:fbf7/1282c19:dd:d9:dd:c25:c25b:d00a:fbf7
2492c19:dd:d9:dd:c25:c25b:d00a:fbf8/1282c19:dd:d9:dd:c25:c25b:d00a:fbf8
2502c19:dd:d9:dd:c25:c25b:d00a:fbf9/1282c19:dd:d9:dd:c25:c25b:d00a:fbf9
2512c19:dd:d9:dd:c25:c25b:d00a:fbfa/1282c19:dd:d9:dd:c25:c25b:d00a:fbfa
2522c19:dd:d9:dd:c25:c25b:d00a:fbfb/1282c19:dd:d9:dd:c25:c25b:d00a:fbfb
2532c19:dd:d9:dd:c25:c25b:d00a:fbfc/1282c19:dd:d9:dd:c25:c25b:d00a:fbfc
2542c19:dd:d9:dd:c25:c25b:d00a:fbfd/1282c19:dd:d9:dd:c25:c25b:d00a:fbfd
2552c19:dd:d9:dd:c25:c25b:d00a:fbfe/1282c19:dd:d9:dd:c25:c25b:d00a:fbfe
2562c19:dd:d9:dd:c25:c25b:d00a:fbff/1282c19:dd:d9:dd:c25:c25b:d00a:fbff

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.