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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:dd0:ec00:c25:c25:dd4e:ce00/120
First address
2c19:dd:dd0:ec00:c25:c25:dd4e:ce00
Last address
2c19:dd:dd0:ec00:c25:c25:dd4e:ceff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0dd0:ec00:0c25:0c25:dd4e:ce00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
e.c.e.4.d.d.5.2.c.0.5.2.c.0.0.0.c.e.0.d.d.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:dd0:ec00:c25:c25:dd4e:ce00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:dd0:ec00:c25:c25:dd4e:ce00/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce00
22c19:dd:dd0:ec00:c25:c25:dd4e:ce01/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce01
32c19:dd:dd0:ec00:c25:c25:dd4e:ce02/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce02
42c19:dd:dd0:ec00:c25:c25:dd4e:ce03/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce03
52c19:dd:dd0:ec00:c25:c25:dd4e:ce04/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce04
62c19:dd:dd0:ec00:c25:c25:dd4e:ce05/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce05
72c19:dd:dd0:ec00:c25:c25:dd4e:ce06/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce06
82c19:dd:dd0:ec00:c25:c25:dd4e:ce07/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce07
92c19:dd:dd0:ec00:c25:c25:dd4e:ce08/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce08
102c19:dd:dd0:ec00:c25:c25:dd4e:ce09/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce09
112c19:dd:dd0:ec00:c25:c25:dd4e:ce0a/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce0a
122c19:dd:dd0:ec00:c25:c25:dd4e:ce0b/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce0b
132c19:dd:dd0:ec00:c25:c25:dd4e:ce0c/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce0c
142c19:dd:dd0:ec00:c25:c25:dd4e:ce0d/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce0d
152c19:dd:dd0:ec00:c25:c25:dd4e:ce0e/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce0e
162c19:dd:dd0:ec00:c25:c25:dd4e:ce0f/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce0f
172c19:dd:dd0:ec00:c25:c25:dd4e:ce10/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce10
182c19:dd:dd0:ec00:c25:c25:dd4e:ce11/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce11
192c19:dd:dd0:ec00:c25:c25:dd4e:ce12/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce12
202c19:dd:dd0:ec00:c25:c25:dd4e:ce13/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce13
212c19:dd:dd0:ec00:c25:c25:dd4e:ce14/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce14
222c19:dd:dd0:ec00:c25:c25:dd4e:ce15/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce15
232c19:dd:dd0:ec00:c25:c25:dd4e:ce16/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce16
242c19:dd:dd0:ec00:c25:c25:dd4e:ce17/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce17
252c19:dd:dd0:ec00:c25:c25:dd4e:ce18/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce18
262c19:dd:dd0:ec00:c25:c25:dd4e:ce19/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce19
272c19:dd:dd0:ec00:c25:c25:dd4e:ce1a/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce1a
282c19:dd:dd0:ec00:c25:c25:dd4e:ce1b/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce1b
292c19:dd:dd0:ec00:c25:c25:dd4e:ce1c/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce1c
302c19:dd:dd0:ec00:c25:c25:dd4e:ce1d/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce1d
312c19:dd:dd0:ec00:c25:c25:dd4e:ce1e/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce1e
322c19:dd:dd0:ec00:c25:c25:dd4e:ce1f/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce1f
332c19:dd:dd0:ec00:c25:c25:dd4e:ce20/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce20
342c19:dd:dd0:ec00:c25:c25:dd4e:ce21/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce21
352c19:dd:dd0:ec00:c25:c25:dd4e:ce22/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce22
362c19:dd:dd0:ec00:c25:c25:dd4e:ce23/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce23
372c19:dd:dd0:ec00:c25:c25:dd4e:ce24/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce24
382c19:dd:dd0:ec00:c25:c25:dd4e:ce25/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce25
392c19:dd:dd0:ec00:c25:c25:dd4e:ce26/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce26
402c19:dd:dd0:ec00:c25:c25:dd4e:ce27/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce27
412c19:dd:dd0:ec00:c25:c25:dd4e:ce28/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce28
422c19:dd:dd0:ec00:c25:c25:dd4e:ce29/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce29
432c19:dd:dd0:ec00:c25:c25:dd4e:ce2a/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce2a
442c19:dd:dd0:ec00:c25:c25:dd4e:ce2b/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce2b
452c19:dd:dd0:ec00:c25:c25:dd4e:ce2c/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce2c
462c19:dd:dd0:ec00:c25:c25:dd4e:ce2d/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce2d
472c19:dd:dd0:ec00:c25:c25:dd4e:ce2e/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce2e
482c19:dd:dd0:ec00:c25:c25:dd4e:ce2f/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce2f
492c19:dd:dd0:ec00:c25:c25:dd4e:ce30/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce30
502c19:dd:dd0:ec00:c25:c25:dd4e:ce31/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce31
512c19:dd:dd0:ec00:c25:c25:dd4e:ce32/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce32
522c19:dd:dd0:ec00:c25:c25:dd4e:ce33/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce33
532c19:dd:dd0:ec00:c25:c25:dd4e:ce34/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce34
542c19:dd:dd0:ec00:c25:c25:dd4e:ce35/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce35
552c19:dd:dd0:ec00:c25:c25:dd4e:ce36/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce36
562c19:dd:dd0:ec00:c25:c25:dd4e:ce37/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce37
572c19:dd:dd0:ec00:c25:c25:dd4e:ce38/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce38
582c19:dd:dd0:ec00:c25:c25:dd4e:ce39/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce39
592c19:dd:dd0:ec00:c25:c25:dd4e:ce3a/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce3a
602c19:dd:dd0:ec00:c25:c25:dd4e:ce3b/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce3b
612c19:dd:dd0:ec00:c25:c25:dd4e:ce3c/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce3c
622c19:dd:dd0:ec00:c25:c25:dd4e:ce3d/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce3d
632c19:dd:dd0:ec00:c25:c25:dd4e:ce3e/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce3e
642c19:dd:dd0:ec00:c25:c25:dd4e:ce3f/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce3f
652c19:dd:dd0:ec00:c25:c25:dd4e:ce40/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce40
662c19:dd:dd0:ec00:c25:c25:dd4e:ce41/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce41
672c19:dd:dd0:ec00:c25:c25:dd4e:ce42/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce42
682c19:dd:dd0:ec00:c25:c25:dd4e:ce43/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce43
692c19:dd:dd0:ec00:c25:c25:dd4e:ce44/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce44
702c19:dd:dd0:ec00:c25:c25:dd4e:ce45/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce45
712c19:dd:dd0:ec00:c25:c25:dd4e:ce46/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce46
722c19:dd:dd0:ec00:c25:c25:dd4e:ce47/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce47
732c19:dd:dd0:ec00:c25:c25:dd4e:ce48/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce48
742c19:dd:dd0:ec00:c25:c25:dd4e:ce49/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce49
752c19:dd:dd0:ec00:c25:c25:dd4e:ce4a/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce4a
762c19:dd:dd0:ec00:c25:c25:dd4e:ce4b/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce4b
772c19:dd:dd0:ec00:c25:c25:dd4e:ce4c/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce4c
782c19:dd:dd0:ec00:c25:c25:dd4e:ce4d/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce4d
792c19:dd:dd0:ec00:c25:c25:dd4e:ce4e/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce4e
802c19:dd:dd0:ec00:c25:c25:dd4e:ce4f/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce4f
812c19:dd:dd0:ec00:c25:c25:dd4e:ce50/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce50
822c19:dd:dd0:ec00:c25:c25:dd4e:ce51/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce51
832c19:dd:dd0:ec00:c25:c25:dd4e:ce52/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce52
842c19:dd:dd0:ec00:c25:c25:dd4e:ce53/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce53
852c19:dd:dd0:ec00:c25:c25:dd4e:ce54/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce54
862c19:dd:dd0:ec00:c25:c25:dd4e:ce55/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce55
872c19:dd:dd0:ec00:c25:c25:dd4e:ce56/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce56
882c19:dd:dd0:ec00:c25:c25:dd4e:ce57/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce57
892c19:dd:dd0:ec00:c25:c25:dd4e:ce58/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce58
902c19:dd:dd0:ec00:c25:c25:dd4e:ce59/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce59
912c19:dd:dd0:ec00:c25:c25:dd4e:ce5a/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce5a
922c19:dd:dd0:ec00:c25:c25:dd4e:ce5b/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce5b
932c19:dd:dd0:ec00:c25:c25:dd4e:ce5c/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce5c
942c19:dd:dd0:ec00:c25:c25:dd4e:ce5d/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce5d
952c19:dd:dd0:ec00:c25:c25:dd4e:ce5e/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce5e
962c19:dd:dd0:ec00:c25:c25:dd4e:ce5f/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce5f
972c19:dd:dd0:ec00:c25:c25:dd4e:ce60/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce60
982c19:dd:dd0:ec00:c25:c25:dd4e:ce61/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce61
992c19:dd:dd0:ec00:c25:c25:dd4e:ce62/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce62
1002c19:dd:dd0:ec00:c25:c25:dd4e:ce63/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce63
1012c19:dd:dd0:ec00:c25:c25:dd4e:ce64/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce64
1022c19:dd:dd0:ec00:c25:c25:dd4e:ce65/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce65
1032c19:dd:dd0:ec00:c25:c25:dd4e:ce66/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce66
1042c19:dd:dd0:ec00:c25:c25:dd4e:ce67/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce67
1052c19:dd:dd0:ec00:c25:c25:dd4e:ce68/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce68
1062c19:dd:dd0:ec00:c25:c25:dd4e:ce69/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce69
1072c19:dd:dd0:ec00:c25:c25:dd4e:ce6a/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce6a
1082c19:dd:dd0:ec00:c25:c25:dd4e:ce6b/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce6b
1092c19:dd:dd0:ec00:c25:c25:dd4e:ce6c/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce6c
1102c19:dd:dd0:ec00:c25:c25:dd4e:ce6d/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce6d
1112c19:dd:dd0:ec00:c25:c25:dd4e:ce6e/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce6e
1122c19:dd:dd0:ec00:c25:c25:dd4e:ce6f/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce6f
1132c19:dd:dd0:ec00:c25:c25:dd4e:ce70/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce70
1142c19:dd:dd0:ec00:c25:c25:dd4e:ce71/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce71
1152c19:dd:dd0:ec00:c25:c25:dd4e:ce72/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce72
1162c19:dd:dd0:ec00:c25:c25:dd4e:ce73/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce73
1172c19:dd:dd0:ec00:c25:c25:dd4e:ce74/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce74
1182c19:dd:dd0:ec00:c25:c25:dd4e:ce75/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce75
1192c19:dd:dd0:ec00:c25:c25:dd4e:ce76/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce76
1202c19:dd:dd0:ec00:c25:c25:dd4e:ce77/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce77
1212c19:dd:dd0:ec00:c25:c25:dd4e:ce78/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce78
1222c19:dd:dd0:ec00:c25:c25:dd4e:ce79/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce79
1232c19:dd:dd0:ec00:c25:c25:dd4e:ce7a/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce7a
1242c19:dd:dd0:ec00:c25:c25:dd4e:ce7b/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce7b
1252c19:dd:dd0:ec00:c25:c25:dd4e:ce7c/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce7c
1262c19:dd:dd0:ec00:c25:c25:dd4e:ce7d/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce7d
1272c19:dd:dd0:ec00:c25:c25:dd4e:ce7e/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce7e
1282c19:dd:dd0:ec00:c25:c25:dd4e:ce7f/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce7f
1292c19:dd:dd0:ec00:c25:c25:dd4e:ce80/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce80
1302c19:dd:dd0:ec00:c25:c25:dd4e:ce81/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce81
1312c19:dd:dd0:ec00:c25:c25:dd4e:ce82/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce82
1322c19:dd:dd0:ec00:c25:c25:dd4e:ce83/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce83
1332c19:dd:dd0:ec00:c25:c25:dd4e:ce84/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce84
1342c19:dd:dd0:ec00:c25:c25:dd4e:ce85/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce85
1352c19:dd:dd0:ec00:c25:c25:dd4e:ce86/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce86
1362c19:dd:dd0:ec00:c25:c25:dd4e:ce87/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce87
1372c19:dd:dd0:ec00:c25:c25:dd4e:ce88/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce88
1382c19:dd:dd0:ec00:c25:c25:dd4e:ce89/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce89
1392c19:dd:dd0:ec00:c25:c25:dd4e:ce8a/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce8a
1402c19:dd:dd0:ec00:c25:c25:dd4e:ce8b/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce8b
1412c19:dd:dd0:ec00:c25:c25:dd4e:ce8c/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce8c
1422c19:dd:dd0:ec00:c25:c25:dd4e:ce8d/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce8d
1432c19:dd:dd0:ec00:c25:c25:dd4e:ce8e/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce8e
1442c19:dd:dd0:ec00:c25:c25:dd4e:ce8f/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce8f
1452c19:dd:dd0:ec00:c25:c25:dd4e:ce90/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce90
1462c19:dd:dd0:ec00:c25:c25:dd4e:ce91/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce91
1472c19:dd:dd0:ec00:c25:c25:dd4e:ce92/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce92
1482c19:dd:dd0:ec00:c25:c25:dd4e:ce93/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce93
1492c19:dd:dd0:ec00:c25:c25:dd4e:ce94/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce94
1502c19:dd:dd0:ec00:c25:c25:dd4e:ce95/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce95
1512c19:dd:dd0:ec00:c25:c25:dd4e:ce96/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce96
1522c19:dd:dd0:ec00:c25:c25:dd4e:ce97/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce97
1532c19:dd:dd0:ec00:c25:c25:dd4e:ce98/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce98
1542c19:dd:dd0:ec00:c25:c25:dd4e:ce99/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce99
1552c19:dd:dd0:ec00:c25:c25:dd4e:ce9a/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce9a
1562c19:dd:dd0:ec00:c25:c25:dd4e:ce9b/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce9b
1572c19:dd:dd0:ec00:c25:c25:dd4e:ce9c/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce9c
1582c19:dd:dd0:ec00:c25:c25:dd4e:ce9d/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce9d
1592c19:dd:dd0:ec00:c25:c25:dd4e:ce9e/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce9e
1602c19:dd:dd0:ec00:c25:c25:dd4e:ce9f/1282c19:dd:dd0:ec00:c25:c25:dd4e:ce9f
1612c19:dd:dd0:ec00:c25:c25:dd4e:cea0/1282c19:dd:dd0:ec00:c25:c25:dd4e:cea0
1622c19:dd:dd0:ec00:c25:c25:dd4e:cea1/1282c19:dd:dd0:ec00:c25:c25:dd4e:cea1
1632c19:dd:dd0:ec00:c25:c25:dd4e:cea2/1282c19:dd:dd0:ec00:c25:c25:dd4e:cea2
1642c19:dd:dd0:ec00:c25:c25:dd4e:cea3/1282c19:dd:dd0:ec00:c25:c25:dd4e:cea3
1652c19:dd:dd0:ec00:c25:c25:dd4e:cea4/1282c19:dd:dd0:ec00:c25:c25:dd4e:cea4
1662c19:dd:dd0:ec00:c25:c25:dd4e:cea5/1282c19:dd:dd0:ec00:c25:c25:dd4e:cea5
1672c19:dd:dd0:ec00:c25:c25:dd4e:cea6/1282c19:dd:dd0:ec00:c25:c25:dd4e:cea6
1682c19:dd:dd0:ec00:c25:c25:dd4e:cea7/1282c19:dd:dd0:ec00:c25:c25:dd4e:cea7
1692c19:dd:dd0:ec00:c25:c25:dd4e:cea8/1282c19:dd:dd0:ec00:c25:c25:dd4e:cea8
1702c19:dd:dd0:ec00:c25:c25:dd4e:cea9/1282c19:dd:dd0:ec00:c25:c25:dd4e:cea9
1712c19:dd:dd0:ec00:c25:c25:dd4e:ceaa/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceaa
1722c19:dd:dd0:ec00:c25:c25:dd4e:ceab/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceab
1732c19:dd:dd0:ec00:c25:c25:dd4e:ceac/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceac
1742c19:dd:dd0:ec00:c25:c25:dd4e:cead/1282c19:dd:dd0:ec00:c25:c25:dd4e:cead
1752c19:dd:dd0:ec00:c25:c25:dd4e:ceae/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceae
1762c19:dd:dd0:ec00:c25:c25:dd4e:ceaf/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceaf
1772c19:dd:dd0:ec00:c25:c25:dd4e:ceb0/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceb0
1782c19:dd:dd0:ec00:c25:c25:dd4e:ceb1/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceb1
1792c19:dd:dd0:ec00:c25:c25:dd4e:ceb2/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceb2
1802c19:dd:dd0:ec00:c25:c25:dd4e:ceb3/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceb3
1812c19:dd:dd0:ec00:c25:c25:dd4e:ceb4/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceb4
1822c19:dd:dd0:ec00:c25:c25:dd4e:ceb5/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceb5
1832c19:dd:dd0:ec00:c25:c25:dd4e:ceb6/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceb6
1842c19:dd:dd0:ec00:c25:c25:dd4e:ceb7/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceb7
1852c19:dd:dd0:ec00:c25:c25:dd4e:ceb8/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceb8
1862c19:dd:dd0:ec00:c25:c25:dd4e:ceb9/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceb9
1872c19:dd:dd0:ec00:c25:c25:dd4e:ceba/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceba
1882c19:dd:dd0:ec00:c25:c25:dd4e:cebb/1282c19:dd:dd0:ec00:c25:c25:dd4e:cebb
1892c19:dd:dd0:ec00:c25:c25:dd4e:cebc/1282c19:dd:dd0:ec00:c25:c25:dd4e:cebc
1902c19:dd:dd0:ec00:c25:c25:dd4e:cebd/1282c19:dd:dd0:ec00:c25:c25:dd4e:cebd
1912c19:dd:dd0:ec00:c25:c25:dd4e:cebe/1282c19:dd:dd0:ec00:c25:c25:dd4e:cebe
1922c19:dd:dd0:ec00:c25:c25:dd4e:cebf/1282c19:dd:dd0:ec00:c25:c25:dd4e:cebf
1932c19:dd:dd0:ec00:c25:c25:dd4e:cec0/1282c19:dd:dd0:ec00:c25:c25:dd4e:cec0
1942c19:dd:dd0:ec00:c25:c25:dd4e:cec1/1282c19:dd:dd0:ec00:c25:c25:dd4e:cec1
1952c19:dd:dd0:ec00:c25:c25:dd4e:cec2/1282c19:dd:dd0:ec00:c25:c25:dd4e:cec2
1962c19:dd:dd0:ec00:c25:c25:dd4e:cec3/1282c19:dd:dd0:ec00:c25:c25:dd4e:cec3
1972c19:dd:dd0:ec00:c25:c25:dd4e:cec4/1282c19:dd:dd0:ec00:c25:c25:dd4e:cec4
1982c19:dd:dd0:ec00:c25:c25:dd4e:cec5/1282c19:dd:dd0:ec00:c25:c25:dd4e:cec5
1992c19:dd:dd0:ec00:c25:c25:dd4e:cec6/1282c19:dd:dd0:ec00:c25:c25:dd4e:cec6
2002c19:dd:dd0:ec00:c25:c25:dd4e:cec7/1282c19:dd:dd0:ec00:c25:c25:dd4e:cec7
2012c19:dd:dd0:ec00:c25:c25:dd4e:cec8/1282c19:dd:dd0:ec00:c25:c25:dd4e:cec8
2022c19:dd:dd0:ec00:c25:c25:dd4e:cec9/1282c19:dd:dd0:ec00:c25:c25:dd4e:cec9
2032c19:dd:dd0:ec00:c25:c25:dd4e:ceca/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceca
2042c19:dd:dd0:ec00:c25:c25:dd4e:cecb/1282c19:dd:dd0:ec00:c25:c25:dd4e:cecb
2052c19:dd:dd0:ec00:c25:c25:dd4e:cecc/1282c19:dd:dd0:ec00:c25:c25:dd4e:cecc
2062c19:dd:dd0:ec00:c25:c25:dd4e:cecd/1282c19:dd:dd0:ec00:c25:c25:dd4e:cecd
2072c19:dd:dd0:ec00:c25:c25:dd4e:cece/1282c19:dd:dd0:ec00:c25:c25:dd4e:cece
2082c19:dd:dd0:ec00:c25:c25:dd4e:cecf/1282c19:dd:dd0:ec00:c25:c25:dd4e:cecf
2092c19:dd:dd0:ec00:c25:c25:dd4e:ced0/1282c19:dd:dd0:ec00:c25:c25:dd4e:ced0
2102c19:dd:dd0:ec00:c25:c25:dd4e:ced1/1282c19:dd:dd0:ec00:c25:c25:dd4e:ced1
2112c19:dd:dd0:ec00:c25:c25:dd4e:ced2/1282c19:dd:dd0:ec00:c25:c25:dd4e:ced2
2122c19:dd:dd0:ec00:c25:c25:dd4e:ced3/1282c19:dd:dd0:ec00:c25:c25:dd4e:ced3
2132c19:dd:dd0:ec00:c25:c25:dd4e:ced4/1282c19:dd:dd0:ec00:c25:c25:dd4e:ced4
2142c19:dd:dd0:ec00:c25:c25:dd4e:ced5/1282c19:dd:dd0:ec00:c25:c25:dd4e:ced5
2152c19:dd:dd0:ec00:c25:c25:dd4e:ced6/1282c19:dd:dd0:ec00:c25:c25:dd4e:ced6
2162c19:dd:dd0:ec00:c25:c25:dd4e:ced7/1282c19:dd:dd0:ec00:c25:c25:dd4e:ced7
2172c19:dd:dd0:ec00:c25:c25:dd4e:ced8/1282c19:dd:dd0:ec00:c25:c25:dd4e:ced8
2182c19:dd:dd0:ec00:c25:c25:dd4e:ced9/1282c19:dd:dd0:ec00:c25:c25:dd4e:ced9
2192c19:dd:dd0:ec00:c25:c25:dd4e:ceda/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceda
2202c19:dd:dd0:ec00:c25:c25:dd4e:cedb/1282c19:dd:dd0:ec00:c25:c25:dd4e:cedb
2212c19:dd:dd0:ec00:c25:c25:dd4e:cedc/1282c19:dd:dd0:ec00:c25:c25:dd4e:cedc
2222c19:dd:dd0:ec00:c25:c25:dd4e:cedd/1282c19:dd:dd0:ec00:c25:c25:dd4e:cedd
2232c19:dd:dd0:ec00:c25:c25:dd4e:cede/1282c19:dd:dd0:ec00:c25:c25:dd4e:cede
2242c19:dd:dd0:ec00:c25:c25:dd4e:cedf/1282c19:dd:dd0:ec00:c25:c25:dd4e:cedf
2252c19:dd:dd0:ec00:c25:c25:dd4e:cee0/1282c19:dd:dd0:ec00:c25:c25:dd4e:cee0
2262c19:dd:dd0:ec00:c25:c25:dd4e:cee1/1282c19:dd:dd0:ec00:c25:c25:dd4e:cee1
2272c19:dd:dd0:ec00:c25:c25:dd4e:cee2/1282c19:dd:dd0:ec00:c25:c25:dd4e:cee2
2282c19:dd:dd0:ec00:c25:c25:dd4e:cee3/1282c19:dd:dd0:ec00:c25:c25:dd4e:cee3
2292c19:dd:dd0:ec00:c25:c25:dd4e:cee4/1282c19:dd:dd0:ec00:c25:c25:dd4e:cee4
2302c19:dd:dd0:ec00:c25:c25:dd4e:cee5/1282c19:dd:dd0:ec00:c25:c25:dd4e:cee5
2312c19:dd:dd0:ec00:c25:c25:dd4e:cee6/1282c19:dd:dd0:ec00:c25:c25:dd4e:cee6
2322c19:dd:dd0:ec00:c25:c25:dd4e:cee7/1282c19:dd:dd0:ec00:c25:c25:dd4e:cee7
2332c19:dd:dd0:ec00:c25:c25:dd4e:cee8/1282c19:dd:dd0:ec00:c25:c25:dd4e:cee8
2342c19:dd:dd0:ec00:c25:c25:dd4e:cee9/1282c19:dd:dd0:ec00:c25:c25:dd4e:cee9
2352c19:dd:dd0:ec00:c25:c25:dd4e:ceea/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceea
2362c19:dd:dd0:ec00:c25:c25:dd4e:ceeb/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceeb
2372c19:dd:dd0:ec00:c25:c25:dd4e:ceec/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceec
2382c19:dd:dd0:ec00:c25:c25:dd4e:ceed/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceed
2392c19:dd:dd0:ec00:c25:c25:dd4e:ceee/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceee
2402c19:dd:dd0:ec00:c25:c25:dd4e:ceef/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceef
2412c19:dd:dd0:ec00:c25:c25:dd4e:cef0/1282c19:dd:dd0:ec00:c25:c25:dd4e:cef0
2422c19:dd:dd0:ec00:c25:c25:dd4e:cef1/1282c19:dd:dd0:ec00:c25:c25:dd4e:cef1
2432c19:dd:dd0:ec00:c25:c25:dd4e:cef2/1282c19:dd:dd0:ec00:c25:c25:dd4e:cef2
2442c19:dd:dd0:ec00:c25:c25:dd4e:cef3/1282c19:dd:dd0:ec00:c25:c25:dd4e:cef3
2452c19:dd:dd0:ec00:c25:c25:dd4e:cef4/1282c19:dd:dd0:ec00:c25:c25:dd4e:cef4
2462c19:dd:dd0:ec00:c25:c25:dd4e:cef5/1282c19:dd:dd0:ec00:c25:c25:dd4e:cef5
2472c19:dd:dd0:ec00:c25:c25:dd4e:cef6/1282c19:dd:dd0:ec00:c25:c25:dd4e:cef6
2482c19:dd:dd0:ec00:c25:c25:dd4e:cef7/1282c19:dd:dd0:ec00:c25:c25:dd4e:cef7
2492c19:dd:dd0:ec00:c25:c25:dd4e:cef8/1282c19:dd:dd0:ec00:c25:c25:dd4e:cef8
2502c19:dd:dd0:ec00:c25:c25:dd4e:cef9/1282c19:dd:dd0:ec00:c25:c25:dd4e:cef9
2512c19:dd:dd0:ec00:c25:c25:dd4e:cefa/1282c19:dd:dd0:ec00:c25:c25:dd4e:cefa
2522c19:dd:dd0:ec00:c25:c25:dd4e:cefb/1282c19:dd:dd0:ec00:c25:c25:dd4e:cefb
2532c19:dd:dd0:ec00:c25:c25:dd4e:cefc/1282c19:dd:dd0:ec00:c25:c25:dd4e:cefc
2542c19:dd:dd0:ec00:c25:c25:dd4e:cefd/1282c19:dd:dd0:ec00:c25:c25:dd4e:cefd
2552c19:dd:dd0:ec00:c25:c25:dd4e:cefe/1282c19:dd:dd0:ec00:c25:c25:dd4e:cefe
2562c19:dd:dd0:ec00:c25:c25:dd4e:ceff/1282c19:dd:dd0:ec00:c25:c25:dd4e:ceff

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.