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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:ee00/120
First address
2c19:dd:d9:dd:c25:c25b:d00a:ee00
Last address
2c19:dd:d9:dd:c25:c25b:d00a:eeff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25b:d00a:ee00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
e.e.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:ee00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25b:d00a:ee00/1282c19:dd:d9:dd:c25:c25b:d00a:ee00
22c19:dd:d9:dd:c25:c25b:d00a:ee01/1282c19:dd:d9:dd:c25:c25b:d00a:ee01
32c19:dd:d9:dd:c25:c25b:d00a:ee02/1282c19:dd:d9:dd:c25:c25b:d00a:ee02
42c19:dd:d9:dd:c25:c25b:d00a:ee03/1282c19:dd:d9:dd:c25:c25b:d00a:ee03
52c19:dd:d9:dd:c25:c25b:d00a:ee04/1282c19:dd:d9:dd:c25:c25b:d00a:ee04
62c19:dd:d9:dd:c25:c25b:d00a:ee05/1282c19:dd:d9:dd:c25:c25b:d00a:ee05
72c19:dd:d9:dd:c25:c25b:d00a:ee06/1282c19:dd:d9:dd:c25:c25b:d00a:ee06
82c19:dd:d9:dd:c25:c25b:d00a:ee07/1282c19:dd:d9:dd:c25:c25b:d00a:ee07
92c19:dd:d9:dd:c25:c25b:d00a:ee08/1282c19:dd:d9:dd:c25:c25b:d00a:ee08
102c19:dd:d9:dd:c25:c25b:d00a:ee09/1282c19:dd:d9:dd:c25:c25b:d00a:ee09
112c19:dd:d9:dd:c25:c25b:d00a:ee0a/1282c19:dd:d9:dd:c25:c25b:d00a:ee0a
122c19:dd:d9:dd:c25:c25b:d00a:ee0b/1282c19:dd:d9:dd:c25:c25b:d00a:ee0b
132c19:dd:d9:dd:c25:c25b:d00a:ee0c/1282c19:dd:d9:dd:c25:c25b:d00a:ee0c
142c19:dd:d9:dd:c25:c25b:d00a:ee0d/1282c19:dd:d9:dd:c25:c25b:d00a:ee0d
152c19:dd:d9:dd:c25:c25b:d00a:ee0e/1282c19:dd:d9:dd:c25:c25b:d00a:ee0e
162c19:dd:d9:dd:c25:c25b:d00a:ee0f/1282c19:dd:d9:dd:c25:c25b:d00a:ee0f
172c19:dd:d9:dd:c25:c25b:d00a:ee10/1282c19:dd:d9:dd:c25:c25b:d00a:ee10
182c19:dd:d9:dd:c25:c25b:d00a:ee11/1282c19:dd:d9:dd:c25:c25b:d00a:ee11
192c19:dd:d9:dd:c25:c25b:d00a:ee12/1282c19:dd:d9:dd:c25:c25b:d00a:ee12
202c19:dd:d9:dd:c25:c25b:d00a:ee13/1282c19:dd:d9:dd:c25:c25b:d00a:ee13
212c19:dd:d9:dd:c25:c25b:d00a:ee14/1282c19:dd:d9:dd:c25:c25b:d00a:ee14
222c19:dd:d9:dd:c25:c25b:d00a:ee15/1282c19:dd:d9:dd:c25:c25b:d00a:ee15
232c19:dd:d9:dd:c25:c25b:d00a:ee16/1282c19:dd:d9:dd:c25:c25b:d00a:ee16
242c19:dd:d9:dd:c25:c25b:d00a:ee17/1282c19:dd:d9:dd:c25:c25b:d00a:ee17
252c19:dd:d9:dd:c25:c25b:d00a:ee18/1282c19:dd:d9:dd:c25:c25b:d00a:ee18
262c19:dd:d9:dd:c25:c25b:d00a:ee19/1282c19:dd:d9:dd:c25:c25b:d00a:ee19
272c19:dd:d9:dd:c25:c25b:d00a:ee1a/1282c19:dd:d9:dd:c25:c25b:d00a:ee1a
282c19:dd:d9:dd:c25:c25b:d00a:ee1b/1282c19:dd:d9:dd:c25:c25b:d00a:ee1b
292c19:dd:d9:dd:c25:c25b:d00a:ee1c/1282c19:dd:d9:dd:c25:c25b:d00a:ee1c
302c19:dd:d9:dd:c25:c25b:d00a:ee1d/1282c19:dd:d9:dd:c25:c25b:d00a:ee1d
312c19:dd:d9:dd:c25:c25b:d00a:ee1e/1282c19:dd:d9:dd:c25:c25b:d00a:ee1e
322c19:dd:d9:dd:c25:c25b:d00a:ee1f/1282c19:dd:d9:dd:c25:c25b:d00a:ee1f
332c19:dd:d9:dd:c25:c25b:d00a:ee20/1282c19:dd:d9:dd:c25:c25b:d00a:ee20
342c19:dd:d9:dd:c25:c25b:d00a:ee21/1282c19:dd:d9:dd:c25:c25b:d00a:ee21
352c19:dd:d9:dd:c25:c25b:d00a:ee22/1282c19:dd:d9:dd:c25:c25b:d00a:ee22
362c19:dd:d9:dd:c25:c25b:d00a:ee23/1282c19:dd:d9:dd:c25:c25b:d00a:ee23
372c19:dd:d9:dd:c25:c25b:d00a:ee24/1282c19:dd:d9:dd:c25:c25b:d00a:ee24
382c19:dd:d9:dd:c25:c25b:d00a:ee25/1282c19:dd:d9:dd:c25:c25b:d00a:ee25
392c19:dd:d9:dd:c25:c25b:d00a:ee26/1282c19:dd:d9:dd:c25:c25b:d00a:ee26
402c19:dd:d9:dd:c25:c25b:d00a:ee27/1282c19:dd:d9:dd:c25:c25b:d00a:ee27
412c19:dd:d9:dd:c25:c25b:d00a:ee28/1282c19:dd:d9:dd:c25:c25b:d00a:ee28
422c19:dd:d9:dd:c25:c25b:d00a:ee29/1282c19:dd:d9:dd:c25:c25b:d00a:ee29
432c19:dd:d9:dd:c25:c25b:d00a:ee2a/1282c19:dd:d9:dd:c25:c25b:d00a:ee2a
442c19:dd:d9:dd:c25:c25b:d00a:ee2b/1282c19:dd:d9:dd:c25:c25b:d00a:ee2b
452c19:dd:d9:dd:c25:c25b:d00a:ee2c/1282c19:dd:d9:dd:c25:c25b:d00a:ee2c
462c19:dd:d9:dd:c25:c25b:d00a:ee2d/1282c19:dd:d9:dd:c25:c25b:d00a:ee2d
472c19:dd:d9:dd:c25:c25b:d00a:ee2e/1282c19:dd:d9:dd:c25:c25b:d00a:ee2e
482c19:dd:d9:dd:c25:c25b:d00a:ee2f/1282c19:dd:d9:dd:c25:c25b:d00a:ee2f
492c19:dd:d9:dd:c25:c25b:d00a:ee30/1282c19:dd:d9:dd:c25:c25b:d00a:ee30
502c19:dd:d9:dd:c25:c25b:d00a:ee31/1282c19:dd:d9:dd:c25:c25b:d00a:ee31
512c19:dd:d9:dd:c25:c25b:d00a:ee32/1282c19:dd:d9:dd:c25:c25b:d00a:ee32
522c19:dd:d9:dd:c25:c25b:d00a:ee33/1282c19:dd:d9:dd:c25:c25b:d00a:ee33
532c19:dd:d9:dd:c25:c25b:d00a:ee34/1282c19:dd:d9:dd:c25:c25b:d00a:ee34
542c19:dd:d9:dd:c25:c25b:d00a:ee35/1282c19:dd:d9:dd:c25:c25b:d00a:ee35
552c19:dd:d9:dd:c25:c25b:d00a:ee36/1282c19:dd:d9:dd:c25:c25b:d00a:ee36
562c19:dd:d9:dd:c25:c25b:d00a:ee37/1282c19:dd:d9:dd:c25:c25b:d00a:ee37
572c19:dd:d9:dd:c25:c25b:d00a:ee38/1282c19:dd:d9:dd:c25:c25b:d00a:ee38
582c19:dd:d9:dd:c25:c25b:d00a:ee39/1282c19:dd:d9:dd:c25:c25b:d00a:ee39
592c19:dd:d9:dd:c25:c25b:d00a:ee3a/1282c19:dd:d9:dd:c25:c25b:d00a:ee3a
602c19:dd:d9:dd:c25:c25b:d00a:ee3b/1282c19:dd:d9:dd:c25:c25b:d00a:ee3b
612c19:dd:d9:dd:c25:c25b:d00a:ee3c/1282c19:dd:d9:dd:c25:c25b:d00a:ee3c
622c19:dd:d9:dd:c25:c25b:d00a:ee3d/1282c19:dd:d9:dd:c25:c25b:d00a:ee3d
632c19:dd:d9:dd:c25:c25b:d00a:ee3e/1282c19:dd:d9:dd:c25:c25b:d00a:ee3e
642c19:dd:d9:dd:c25:c25b:d00a:ee3f/1282c19:dd:d9:dd:c25:c25b:d00a:ee3f
652c19:dd:d9:dd:c25:c25b:d00a:ee40/1282c19:dd:d9:dd:c25:c25b:d00a:ee40
662c19:dd:d9:dd:c25:c25b:d00a:ee41/1282c19:dd:d9:dd:c25:c25b:d00a:ee41
672c19:dd:d9:dd:c25:c25b:d00a:ee42/1282c19:dd:d9:dd:c25:c25b:d00a:ee42
682c19:dd:d9:dd:c25:c25b:d00a:ee43/1282c19:dd:d9:dd:c25:c25b:d00a:ee43
692c19:dd:d9:dd:c25:c25b:d00a:ee44/1282c19:dd:d9:dd:c25:c25b:d00a:ee44
702c19:dd:d9:dd:c25:c25b:d00a:ee45/1282c19:dd:d9:dd:c25:c25b:d00a:ee45
712c19:dd:d9:dd:c25:c25b:d00a:ee46/1282c19:dd:d9:dd:c25:c25b:d00a:ee46
722c19:dd:d9:dd:c25:c25b:d00a:ee47/1282c19:dd:d9:dd:c25:c25b:d00a:ee47
732c19:dd:d9:dd:c25:c25b:d00a:ee48/1282c19:dd:d9:dd:c25:c25b:d00a:ee48
742c19:dd:d9:dd:c25:c25b:d00a:ee49/1282c19:dd:d9:dd:c25:c25b:d00a:ee49
752c19:dd:d9:dd:c25:c25b:d00a:ee4a/1282c19:dd:d9:dd:c25:c25b:d00a:ee4a
762c19:dd:d9:dd:c25:c25b:d00a:ee4b/1282c19:dd:d9:dd:c25:c25b:d00a:ee4b
772c19:dd:d9:dd:c25:c25b:d00a:ee4c/1282c19:dd:d9:dd:c25:c25b:d00a:ee4c
782c19:dd:d9:dd:c25:c25b:d00a:ee4d/1282c19:dd:d9:dd:c25:c25b:d00a:ee4d
792c19:dd:d9:dd:c25:c25b:d00a:ee4e/1282c19:dd:d9:dd:c25:c25b:d00a:ee4e
802c19:dd:d9:dd:c25:c25b:d00a:ee4f/1282c19:dd:d9:dd:c25:c25b:d00a:ee4f
812c19:dd:d9:dd:c25:c25b:d00a:ee50/1282c19:dd:d9:dd:c25:c25b:d00a:ee50
822c19:dd:d9:dd:c25:c25b:d00a:ee51/1282c19:dd:d9:dd:c25:c25b:d00a:ee51
832c19:dd:d9:dd:c25:c25b:d00a:ee52/1282c19:dd:d9:dd:c25:c25b:d00a:ee52
842c19:dd:d9:dd:c25:c25b:d00a:ee53/1282c19:dd:d9:dd:c25:c25b:d00a:ee53
852c19:dd:d9:dd:c25:c25b:d00a:ee54/1282c19:dd:d9:dd:c25:c25b:d00a:ee54
862c19:dd:d9:dd:c25:c25b:d00a:ee55/1282c19:dd:d9:dd:c25:c25b:d00a:ee55
872c19:dd:d9:dd:c25:c25b:d00a:ee56/1282c19:dd:d9:dd:c25:c25b:d00a:ee56
882c19:dd:d9:dd:c25:c25b:d00a:ee57/1282c19:dd:d9:dd:c25:c25b:d00a:ee57
892c19:dd:d9:dd:c25:c25b:d00a:ee58/1282c19:dd:d9:dd:c25:c25b:d00a:ee58
902c19:dd:d9:dd:c25:c25b:d00a:ee59/1282c19:dd:d9:dd:c25:c25b:d00a:ee59
912c19:dd:d9:dd:c25:c25b:d00a:ee5a/1282c19:dd:d9:dd:c25:c25b:d00a:ee5a
922c19:dd:d9:dd:c25:c25b:d00a:ee5b/1282c19:dd:d9:dd:c25:c25b:d00a:ee5b
932c19:dd:d9:dd:c25:c25b:d00a:ee5c/1282c19:dd:d9:dd:c25:c25b:d00a:ee5c
942c19:dd:d9:dd:c25:c25b:d00a:ee5d/1282c19:dd:d9:dd:c25:c25b:d00a:ee5d
952c19:dd:d9:dd:c25:c25b:d00a:ee5e/1282c19:dd:d9:dd:c25:c25b:d00a:ee5e
962c19:dd:d9:dd:c25:c25b:d00a:ee5f/1282c19:dd:d9:dd:c25:c25b:d00a:ee5f
972c19:dd:d9:dd:c25:c25b:d00a:ee60/1282c19:dd:d9:dd:c25:c25b:d00a:ee60
982c19:dd:d9:dd:c25:c25b:d00a:ee61/1282c19:dd:d9:dd:c25:c25b:d00a:ee61
992c19:dd:d9:dd:c25:c25b:d00a:ee62/1282c19:dd:d9:dd:c25:c25b:d00a:ee62
1002c19:dd:d9:dd:c25:c25b:d00a:ee63/1282c19:dd:d9:dd:c25:c25b:d00a:ee63
1012c19:dd:d9:dd:c25:c25b:d00a:ee64/1282c19:dd:d9:dd:c25:c25b:d00a:ee64
1022c19:dd:d9:dd:c25:c25b:d00a:ee65/1282c19:dd:d9:dd:c25:c25b:d00a:ee65
1032c19:dd:d9:dd:c25:c25b:d00a:ee66/1282c19:dd:d9:dd:c25:c25b:d00a:ee66
1042c19:dd:d9:dd:c25:c25b:d00a:ee67/1282c19:dd:d9:dd:c25:c25b:d00a:ee67
1052c19:dd:d9:dd:c25:c25b:d00a:ee68/1282c19:dd:d9:dd:c25:c25b:d00a:ee68
1062c19:dd:d9:dd:c25:c25b:d00a:ee69/1282c19:dd:d9:dd:c25:c25b:d00a:ee69
1072c19:dd:d9:dd:c25:c25b:d00a:ee6a/1282c19:dd:d9:dd:c25:c25b:d00a:ee6a
1082c19:dd:d9:dd:c25:c25b:d00a:ee6b/1282c19:dd:d9:dd:c25:c25b:d00a:ee6b
1092c19:dd:d9:dd:c25:c25b:d00a:ee6c/1282c19:dd:d9:dd:c25:c25b:d00a:ee6c
1102c19:dd:d9:dd:c25:c25b:d00a:ee6d/1282c19:dd:d9:dd:c25:c25b:d00a:ee6d
1112c19:dd:d9:dd:c25:c25b:d00a:ee6e/1282c19:dd:d9:dd:c25:c25b:d00a:ee6e
1122c19:dd:d9:dd:c25:c25b:d00a:ee6f/1282c19:dd:d9:dd:c25:c25b:d00a:ee6f
1132c19:dd:d9:dd:c25:c25b:d00a:ee70/1282c19:dd:d9:dd:c25:c25b:d00a:ee70
1142c19:dd:d9:dd:c25:c25b:d00a:ee71/1282c19:dd:d9:dd:c25:c25b:d00a:ee71
1152c19:dd:d9:dd:c25:c25b:d00a:ee72/1282c19:dd:d9:dd:c25:c25b:d00a:ee72
1162c19:dd:d9:dd:c25:c25b:d00a:ee73/1282c19:dd:d9:dd:c25:c25b:d00a:ee73
1172c19:dd:d9:dd:c25:c25b:d00a:ee74/1282c19:dd:d9:dd:c25:c25b:d00a:ee74
1182c19:dd:d9:dd:c25:c25b:d00a:ee75/1282c19:dd:d9:dd:c25:c25b:d00a:ee75
1192c19:dd:d9:dd:c25:c25b:d00a:ee76/1282c19:dd:d9:dd:c25:c25b:d00a:ee76
1202c19:dd:d9:dd:c25:c25b:d00a:ee77/1282c19:dd:d9:dd:c25:c25b:d00a:ee77
1212c19:dd:d9:dd:c25:c25b:d00a:ee78/1282c19:dd:d9:dd:c25:c25b:d00a:ee78
1222c19:dd:d9:dd:c25:c25b:d00a:ee79/1282c19:dd:d9:dd:c25:c25b:d00a:ee79
1232c19:dd:d9:dd:c25:c25b:d00a:ee7a/1282c19:dd:d9:dd:c25:c25b:d00a:ee7a
1242c19:dd:d9:dd:c25:c25b:d00a:ee7b/1282c19:dd:d9:dd:c25:c25b:d00a:ee7b
1252c19:dd:d9:dd:c25:c25b:d00a:ee7c/1282c19:dd:d9:dd:c25:c25b:d00a:ee7c
1262c19:dd:d9:dd:c25:c25b:d00a:ee7d/1282c19:dd:d9:dd:c25:c25b:d00a:ee7d
1272c19:dd:d9:dd:c25:c25b:d00a:ee7e/1282c19:dd:d9:dd:c25:c25b:d00a:ee7e
1282c19:dd:d9:dd:c25:c25b:d00a:ee7f/1282c19:dd:d9:dd:c25:c25b:d00a:ee7f
1292c19:dd:d9:dd:c25:c25b:d00a:ee80/1282c19:dd:d9:dd:c25:c25b:d00a:ee80
1302c19:dd:d9:dd:c25:c25b:d00a:ee81/1282c19:dd:d9:dd:c25:c25b:d00a:ee81
1312c19:dd:d9:dd:c25:c25b:d00a:ee82/1282c19:dd:d9:dd:c25:c25b:d00a:ee82
1322c19:dd:d9:dd:c25:c25b:d00a:ee83/1282c19:dd:d9:dd:c25:c25b:d00a:ee83
1332c19:dd:d9:dd:c25:c25b:d00a:ee84/1282c19:dd:d9:dd:c25:c25b:d00a:ee84
1342c19:dd:d9:dd:c25:c25b:d00a:ee85/1282c19:dd:d9:dd:c25:c25b:d00a:ee85
1352c19:dd:d9:dd:c25:c25b:d00a:ee86/1282c19:dd:d9:dd:c25:c25b:d00a:ee86
1362c19:dd:d9:dd:c25:c25b:d00a:ee87/1282c19:dd:d9:dd:c25:c25b:d00a:ee87
1372c19:dd:d9:dd:c25:c25b:d00a:ee88/1282c19:dd:d9:dd:c25:c25b:d00a:ee88
1382c19:dd:d9:dd:c25:c25b:d00a:ee89/1282c19:dd:d9:dd:c25:c25b:d00a:ee89
1392c19:dd:d9:dd:c25:c25b:d00a:ee8a/1282c19:dd:d9:dd:c25:c25b:d00a:ee8a
1402c19:dd:d9:dd:c25:c25b:d00a:ee8b/1282c19:dd:d9:dd:c25:c25b:d00a:ee8b
1412c19:dd:d9:dd:c25:c25b:d00a:ee8c/1282c19:dd:d9:dd:c25:c25b:d00a:ee8c
1422c19:dd:d9:dd:c25:c25b:d00a:ee8d/1282c19:dd:d9:dd:c25:c25b:d00a:ee8d
1432c19:dd:d9:dd:c25:c25b:d00a:ee8e/1282c19:dd:d9:dd:c25:c25b:d00a:ee8e
1442c19:dd:d9:dd:c25:c25b:d00a:ee8f/1282c19:dd:d9:dd:c25:c25b:d00a:ee8f
1452c19:dd:d9:dd:c25:c25b:d00a:ee90/1282c19:dd:d9:dd:c25:c25b:d00a:ee90
1462c19:dd:d9:dd:c25:c25b:d00a:ee91/1282c19:dd:d9:dd:c25:c25b:d00a:ee91
1472c19:dd:d9:dd:c25:c25b:d00a:ee92/1282c19:dd:d9:dd:c25:c25b:d00a:ee92
1482c19:dd:d9:dd:c25:c25b:d00a:ee93/1282c19:dd:d9:dd:c25:c25b:d00a:ee93
1492c19:dd:d9:dd:c25:c25b:d00a:ee94/1282c19:dd:d9:dd:c25:c25b:d00a:ee94
1502c19:dd:d9:dd:c25:c25b:d00a:ee95/1282c19:dd:d9:dd:c25:c25b:d00a:ee95
1512c19:dd:d9:dd:c25:c25b:d00a:ee96/1282c19:dd:d9:dd:c25:c25b:d00a:ee96
1522c19:dd:d9:dd:c25:c25b:d00a:ee97/1282c19:dd:d9:dd:c25:c25b:d00a:ee97
1532c19:dd:d9:dd:c25:c25b:d00a:ee98/1282c19:dd:d9:dd:c25:c25b:d00a:ee98
1542c19:dd:d9:dd:c25:c25b:d00a:ee99/1282c19:dd:d9:dd:c25:c25b:d00a:ee99
1552c19:dd:d9:dd:c25:c25b:d00a:ee9a/1282c19:dd:d9:dd:c25:c25b:d00a:ee9a
1562c19:dd:d9:dd:c25:c25b:d00a:ee9b/1282c19:dd:d9:dd:c25:c25b:d00a:ee9b
1572c19:dd:d9:dd:c25:c25b:d00a:ee9c/1282c19:dd:d9:dd:c25:c25b:d00a:ee9c
1582c19:dd:d9:dd:c25:c25b:d00a:ee9d/1282c19:dd:d9:dd:c25:c25b:d00a:ee9d
1592c19:dd:d9:dd:c25:c25b:d00a:ee9e/1282c19:dd:d9:dd:c25:c25b:d00a:ee9e
1602c19:dd:d9:dd:c25:c25b:d00a:ee9f/1282c19:dd:d9:dd:c25:c25b:d00a:ee9f
1612c19:dd:d9:dd:c25:c25b:d00a:eea0/1282c19:dd:d9:dd:c25:c25b:d00a:eea0
1622c19:dd:d9:dd:c25:c25b:d00a:eea1/1282c19:dd:d9:dd:c25:c25b:d00a:eea1
1632c19:dd:d9:dd:c25:c25b:d00a:eea2/1282c19:dd:d9:dd:c25:c25b:d00a:eea2
1642c19:dd:d9:dd:c25:c25b:d00a:eea3/1282c19:dd:d9:dd:c25:c25b:d00a:eea3
1652c19:dd:d9:dd:c25:c25b:d00a:eea4/1282c19:dd:d9:dd:c25:c25b:d00a:eea4
1662c19:dd:d9:dd:c25:c25b:d00a:eea5/1282c19:dd:d9:dd:c25:c25b:d00a:eea5
1672c19:dd:d9:dd:c25:c25b:d00a:eea6/1282c19:dd:d9:dd:c25:c25b:d00a:eea6
1682c19:dd:d9:dd:c25:c25b:d00a:eea7/1282c19:dd:d9:dd:c25:c25b:d00a:eea7
1692c19:dd:d9:dd:c25:c25b:d00a:eea8/1282c19:dd:d9:dd:c25:c25b:d00a:eea8
1702c19:dd:d9:dd:c25:c25b:d00a:eea9/1282c19:dd:d9:dd:c25:c25b:d00a:eea9
1712c19:dd:d9:dd:c25:c25b:d00a:eeaa/1282c19:dd:d9:dd:c25:c25b:d00a:eeaa
1722c19:dd:d9:dd:c25:c25b:d00a:eeab/1282c19:dd:d9:dd:c25:c25b:d00a:eeab
1732c19:dd:d9:dd:c25:c25b:d00a:eeac/1282c19:dd:d9:dd:c25:c25b:d00a:eeac
1742c19:dd:d9:dd:c25:c25b:d00a:eead/1282c19:dd:d9:dd:c25:c25b:d00a:eead
1752c19:dd:d9:dd:c25:c25b:d00a:eeae/1282c19:dd:d9:dd:c25:c25b:d00a:eeae
1762c19:dd:d9:dd:c25:c25b:d00a:eeaf/1282c19:dd:d9:dd:c25:c25b:d00a:eeaf
1772c19:dd:d9:dd:c25:c25b:d00a:eeb0/1282c19:dd:d9:dd:c25:c25b:d00a:eeb0
1782c19:dd:d9:dd:c25:c25b:d00a:eeb1/1282c19:dd:d9:dd:c25:c25b:d00a:eeb1
1792c19:dd:d9:dd:c25:c25b:d00a:eeb2/1282c19:dd:d9:dd:c25:c25b:d00a:eeb2
1802c19:dd:d9:dd:c25:c25b:d00a:eeb3/1282c19:dd:d9:dd:c25:c25b:d00a:eeb3
1812c19:dd:d9:dd:c25:c25b:d00a:eeb4/1282c19:dd:d9:dd:c25:c25b:d00a:eeb4
1822c19:dd:d9:dd:c25:c25b:d00a:eeb5/1282c19:dd:d9:dd:c25:c25b:d00a:eeb5
1832c19:dd:d9:dd:c25:c25b:d00a:eeb6/1282c19:dd:d9:dd:c25:c25b:d00a:eeb6
1842c19:dd:d9:dd:c25:c25b:d00a:eeb7/1282c19:dd:d9:dd:c25:c25b:d00a:eeb7
1852c19:dd:d9:dd:c25:c25b:d00a:eeb8/1282c19:dd:d9:dd:c25:c25b:d00a:eeb8
1862c19:dd:d9:dd:c25:c25b:d00a:eeb9/1282c19:dd:d9:dd:c25:c25b:d00a:eeb9
1872c19:dd:d9:dd:c25:c25b:d00a:eeba/1282c19:dd:d9:dd:c25:c25b:d00a:eeba
1882c19:dd:d9:dd:c25:c25b:d00a:eebb/1282c19:dd:d9:dd:c25:c25b:d00a:eebb
1892c19:dd:d9:dd:c25:c25b:d00a:eebc/1282c19:dd:d9:dd:c25:c25b:d00a:eebc
1902c19:dd:d9:dd:c25:c25b:d00a:eebd/1282c19:dd:d9:dd:c25:c25b:d00a:eebd
1912c19:dd:d9:dd:c25:c25b:d00a:eebe/1282c19:dd:d9:dd:c25:c25b:d00a:eebe
1922c19:dd:d9:dd:c25:c25b:d00a:eebf/1282c19:dd:d9:dd:c25:c25b:d00a:eebf
1932c19:dd:d9:dd:c25:c25b:d00a:eec0/1282c19:dd:d9:dd:c25:c25b:d00a:eec0
1942c19:dd:d9:dd:c25:c25b:d00a:eec1/1282c19:dd:d9:dd:c25:c25b:d00a:eec1
1952c19:dd:d9:dd:c25:c25b:d00a:eec2/1282c19:dd:d9:dd:c25:c25b:d00a:eec2
1962c19:dd:d9:dd:c25:c25b:d00a:eec3/1282c19:dd:d9:dd:c25:c25b:d00a:eec3
1972c19:dd:d9:dd:c25:c25b:d00a:eec4/1282c19:dd:d9:dd:c25:c25b:d00a:eec4
1982c19:dd:d9:dd:c25:c25b:d00a:eec5/1282c19:dd:d9:dd:c25:c25b:d00a:eec5
1992c19:dd:d9:dd:c25:c25b:d00a:eec6/1282c19:dd:d9:dd:c25:c25b:d00a:eec6
2002c19:dd:d9:dd:c25:c25b:d00a:eec7/1282c19:dd:d9:dd:c25:c25b:d00a:eec7
2012c19:dd:d9:dd:c25:c25b:d00a:eec8/1282c19:dd:d9:dd:c25:c25b:d00a:eec8
2022c19:dd:d9:dd:c25:c25b:d00a:eec9/1282c19:dd:d9:dd:c25:c25b:d00a:eec9
2032c19:dd:d9:dd:c25:c25b:d00a:eeca/1282c19:dd:d9:dd:c25:c25b:d00a:eeca
2042c19:dd:d9:dd:c25:c25b:d00a:eecb/1282c19:dd:d9:dd:c25:c25b:d00a:eecb
2052c19:dd:d9:dd:c25:c25b:d00a:eecc/1282c19:dd:d9:dd:c25:c25b:d00a:eecc
2062c19:dd:d9:dd:c25:c25b:d00a:eecd/1282c19:dd:d9:dd:c25:c25b:d00a:eecd
2072c19:dd:d9:dd:c25:c25b:d00a:eece/1282c19:dd:d9:dd:c25:c25b:d00a:eece
2082c19:dd:d9:dd:c25:c25b:d00a:eecf/1282c19:dd:d9:dd:c25:c25b:d00a:eecf
2092c19:dd:d9:dd:c25:c25b:d00a:eed0/1282c19:dd:d9:dd:c25:c25b:d00a:eed0
2102c19:dd:d9:dd:c25:c25b:d00a:eed1/1282c19:dd:d9:dd:c25:c25b:d00a:eed1
2112c19:dd:d9:dd:c25:c25b:d00a:eed2/1282c19:dd:d9:dd:c25:c25b:d00a:eed2
2122c19:dd:d9:dd:c25:c25b:d00a:eed3/1282c19:dd:d9:dd:c25:c25b:d00a:eed3
2132c19:dd:d9:dd:c25:c25b:d00a:eed4/1282c19:dd:d9:dd:c25:c25b:d00a:eed4
2142c19:dd:d9:dd:c25:c25b:d00a:eed5/1282c19:dd:d9:dd:c25:c25b:d00a:eed5
2152c19:dd:d9:dd:c25:c25b:d00a:eed6/1282c19:dd:d9:dd:c25:c25b:d00a:eed6
2162c19:dd:d9:dd:c25:c25b:d00a:eed7/1282c19:dd:d9:dd:c25:c25b:d00a:eed7
2172c19:dd:d9:dd:c25:c25b:d00a:eed8/1282c19:dd:d9:dd:c25:c25b:d00a:eed8
2182c19:dd:d9:dd:c25:c25b:d00a:eed9/1282c19:dd:d9:dd:c25:c25b:d00a:eed9
2192c19:dd:d9:dd:c25:c25b:d00a:eeda/1282c19:dd:d9:dd:c25:c25b:d00a:eeda
2202c19:dd:d9:dd:c25:c25b:d00a:eedb/1282c19:dd:d9:dd:c25:c25b:d00a:eedb
2212c19:dd:d9:dd:c25:c25b:d00a:eedc/1282c19:dd:d9:dd:c25:c25b:d00a:eedc
2222c19:dd:d9:dd:c25:c25b:d00a:eedd/1282c19:dd:d9:dd:c25:c25b:d00a:eedd
2232c19:dd:d9:dd:c25:c25b:d00a:eede/1282c19:dd:d9:dd:c25:c25b:d00a:eede
2242c19:dd:d9:dd:c25:c25b:d00a:eedf/1282c19:dd:d9:dd:c25:c25b:d00a:eedf
2252c19:dd:d9:dd:c25:c25b:d00a:eee0/1282c19:dd:d9:dd:c25:c25b:d00a:eee0
2262c19:dd:d9:dd:c25:c25b:d00a:eee1/1282c19:dd:d9:dd:c25:c25b:d00a:eee1
2272c19:dd:d9:dd:c25:c25b:d00a:eee2/1282c19:dd:d9:dd:c25:c25b:d00a:eee2
2282c19:dd:d9:dd:c25:c25b:d00a:eee3/1282c19:dd:d9:dd:c25:c25b:d00a:eee3
2292c19:dd:d9:dd:c25:c25b:d00a:eee4/1282c19:dd:d9:dd:c25:c25b:d00a:eee4
2302c19:dd:d9:dd:c25:c25b:d00a:eee5/1282c19:dd:d9:dd:c25:c25b:d00a:eee5
2312c19:dd:d9:dd:c25:c25b:d00a:eee6/1282c19:dd:d9:dd:c25:c25b:d00a:eee6
2322c19:dd:d9:dd:c25:c25b:d00a:eee7/1282c19:dd:d9:dd:c25:c25b:d00a:eee7
2332c19:dd:d9:dd:c25:c25b:d00a:eee8/1282c19:dd:d9:dd:c25:c25b:d00a:eee8
2342c19:dd:d9:dd:c25:c25b:d00a:eee9/1282c19:dd:d9:dd:c25:c25b:d00a:eee9
2352c19:dd:d9:dd:c25:c25b:d00a:eeea/1282c19:dd:d9:dd:c25:c25b:d00a:eeea
2362c19:dd:d9:dd:c25:c25b:d00a:eeeb/1282c19:dd:d9:dd:c25:c25b:d00a:eeeb
2372c19:dd:d9:dd:c25:c25b:d00a:eeec/1282c19:dd:d9:dd:c25:c25b:d00a:eeec
2382c19:dd:d9:dd:c25:c25b:d00a:eeed/1282c19:dd:d9:dd:c25:c25b:d00a:eeed
2392c19:dd:d9:dd:c25:c25b:d00a:eeee/1282c19:dd:d9:dd:c25:c25b:d00a:eeee
2402c19:dd:d9:dd:c25:c25b:d00a:eeef/1282c19:dd:d9:dd:c25:c25b:d00a:eeef
2412c19:dd:d9:dd:c25:c25b:d00a:eef0/1282c19:dd:d9:dd:c25:c25b:d00a:eef0
2422c19:dd:d9:dd:c25:c25b:d00a:eef1/1282c19:dd:d9:dd:c25:c25b:d00a:eef1
2432c19:dd:d9:dd:c25:c25b:d00a:eef2/1282c19:dd:d9:dd:c25:c25b:d00a:eef2
2442c19:dd:d9:dd:c25:c25b:d00a:eef3/1282c19:dd:d9:dd:c25:c25b:d00a:eef3
2452c19:dd:d9:dd:c25:c25b:d00a:eef4/1282c19:dd:d9:dd:c25:c25b:d00a:eef4
2462c19:dd:d9:dd:c25:c25b:d00a:eef5/1282c19:dd:d9:dd:c25:c25b:d00a:eef5
2472c19:dd:d9:dd:c25:c25b:d00a:eef6/1282c19:dd:d9:dd:c25:c25b:d00a:eef6
2482c19:dd:d9:dd:c25:c25b:d00a:eef7/1282c19:dd:d9:dd:c25:c25b:d00a:eef7
2492c19:dd:d9:dd:c25:c25b:d00a:eef8/1282c19:dd:d9:dd:c25:c25b:d00a:eef8
2502c19:dd:d9:dd:c25:c25b:d00a:eef9/1282c19:dd:d9:dd:c25:c25b:d00a:eef9
2512c19:dd:d9:dd:c25:c25b:d00a:eefa/1282c19:dd:d9:dd:c25:c25b:d00a:eefa
2522c19:dd:d9:dd:c25:c25b:d00a:eefb/1282c19:dd:d9:dd:c25:c25b:d00a:eefb
2532c19:dd:d9:dd:c25:c25b:d00a:eefc/1282c19:dd:d9:dd:c25:c25b:d00a:eefc
2542c19:dd:d9:dd:c25:c25b:d00a:eefd/1282c19:dd:d9:dd:c25:c25b:d00a:eefd
2552c19:dd:d9:dd:c25:c25b:d00a:eefe/1282c19:dd:d9:dd:c25:c25b:d00a:eefe
2562c19:dd:d9:dd:c25:c25b:d00a:eeff/1282c19:dd:d9:dd:c25:c25b:d00a:eeff

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.