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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Prefix/120
Addresses256
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:d915:ab00/120
First address
2c19:dd:d9:dd:c25:c25:d915:ab00
Last address
2c19:dd:d9:dd:c25:c25:d915:abff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:d915:ab00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
b.a.5.1.9.d.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25:d915:ab00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:d915:ab00/1282c19:dd:d9:dd:c25:c25:d915:ab00
22c19:dd:d9:dd:c25:c25:d915:ab01/1282c19:dd:d9:dd:c25:c25:d915:ab01
32c19:dd:d9:dd:c25:c25:d915:ab02/1282c19:dd:d9:dd:c25:c25:d915:ab02
42c19:dd:d9:dd:c25:c25:d915:ab03/1282c19:dd:d9:dd:c25:c25:d915:ab03
52c19:dd:d9:dd:c25:c25:d915:ab04/1282c19:dd:d9:dd:c25:c25:d915:ab04
62c19:dd:d9:dd:c25:c25:d915:ab05/1282c19:dd:d9:dd:c25:c25:d915:ab05
72c19:dd:d9:dd:c25:c25:d915:ab06/1282c19:dd:d9:dd:c25:c25:d915:ab06
82c19:dd:d9:dd:c25:c25:d915:ab07/1282c19:dd:d9:dd:c25:c25:d915:ab07
92c19:dd:d9:dd:c25:c25:d915:ab08/1282c19:dd:d9:dd:c25:c25:d915:ab08
102c19:dd:d9:dd:c25:c25:d915:ab09/1282c19:dd:d9:dd:c25:c25:d915:ab09
112c19:dd:d9:dd:c25:c25:d915:ab0a/1282c19:dd:d9:dd:c25:c25:d915:ab0a
122c19:dd:d9:dd:c25:c25:d915:ab0b/1282c19:dd:d9:dd:c25:c25:d915:ab0b
132c19:dd:d9:dd:c25:c25:d915:ab0c/1282c19:dd:d9:dd:c25:c25:d915:ab0c
142c19:dd:d9:dd:c25:c25:d915:ab0d/1282c19:dd:d9:dd:c25:c25:d915:ab0d
152c19:dd:d9:dd:c25:c25:d915:ab0e/1282c19:dd:d9:dd:c25:c25:d915:ab0e
162c19:dd:d9:dd:c25:c25:d915:ab0f/1282c19:dd:d9:dd:c25:c25:d915:ab0f
172c19:dd:d9:dd:c25:c25:d915:ab10/1282c19:dd:d9:dd:c25:c25:d915:ab10
182c19:dd:d9:dd:c25:c25:d915:ab11/1282c19:dd:d9:dd:c25:c25:d915:ab11
192c19:dd:d9:dd:c25:c25:d915:ab12/1282c19:dd:d9:dd:c25:c25:d915:ab12
202c19:dd:d9:dd:c25:c25:d915:ab13/1282c19:dd:d9:dd:c25:c25:d915:ab13
212c19:dd:d9:dd:c25:c25:d915:ab14/1282c19:dd:d9:dd:c25:c25:d915:ab14
222c19:dd:d9:dd:c25:c25:d915:ab15/1282c19:dd:d9:dd:c25:c25:d915:ab15
232c19:dd:d9:dd:c25:c25:d915:ab16/1282c19:dd:d9:dd:c25:c25:d915:ab16
242c19:dd:d9:dd:c25:c25:d915:ab17/1282c19:dd:d9:dd:c25:c25:d915:ab17
252c19:dd:d9:dd:c25:c25:d915:ab18/1282c19:dd:d9:dd:c25:c25:d915:ab18
262c19:dd:d9:dd:c25:c25:d915:ab19/1282c19:dd:d9:dd:c25:c25:d915:ab19
272c19:dd:d9:dd:c25:c25:d915:ab1a/1282c19:dd:d9:dd:c25:c25:d915:ab1a
282c19:dd:d9:dd:c25:c25:d915:ab1b/1282c19:dd:d9:dd:c25:c25:d915:ab1b
292c19:dd:d9:dd:c25:c25:d915:ab1c/1282c19:dd:d9:dd:c25:c25:d915:ab1c
302c19:dd:d9:dd:c25:c25:d915:ab1d/1282c19:dd:d9:dd:c25:c25:d915:ab1d
312c19:dd:d9:dd:c25:c25:d915:ab1e/1282c19:dd:d9:dd:c25:c25:d915:ab1e
322c19:dd:d9:dd:c25:c25:d915:ab1f/1282c19:dd:d9:dd:c25:c25:d915:ab1f
332c19:dd:d9:dd:c25:c25:d915:ab20/1282c19:dd:d9:dd:c25:c25:d915:ab20
342c19:dd:d9:dd:c25:c25:d915:ab21/1282c19:dd:d9:dd:c25:c25:d915:ab21
352c19:dd:d9:dd:c25:c25:d915:ab22/1282c19:dd:d9:dd:c25:c25:d915:ab22
362c19:dd:d9:dd:c25:c25:d915:ab23/1282c19:dd:d9:dd:c25:c25:d915:ab23
372c19:dd:d9:dd:c25:c25:d915:ab24/1282c19:dd:d9:dd:c25:c25:d915:ab24
382c19:dd:d9:dd:c25:c25:d915:ab25/1282c19:dd:d9:dd:c25:c25:d915:ab25
392c19:dd:d9:dd:c25:c25:d915:ab26/1282c19:dd:d9:dd:c25:c25:d915:ab26
402c19:dd:d9:dd:c25:c25:d915:ab27/1282c19:dd:d9:dd:c25:c25:d915:ab27
412c19:dd:d9:dd:c25:c25:d915:ab28/1282c19:dd:d9:dd:c25:c25:d915:ab28
422c19:dd:d9:dd:c25:c25:d915:ab29/1282c19:dd:d9:dd:c25:c25:d915:ab29
432c19:dd:d9:dd:c25:c25:d915:ab2a/1282c19:dd:d9:dd:c25:c25:d915:ab2a
442c19:dd:d9:dd:c25:c25:d915:ab2b/1282c19:dd:d9:dd:c25:c25:d915:ab2b
452c19:dd:d9:dd:c25:c25:d915:ab2c/1282c19:dd:d9:dd:c25:c25:d915:ab2c
462c19:dd:d9:dd:c25:c25:d915:ab2d/1282c19:dd:d9:dd:c25:c25:d915:ab2d
472c19:dd:d9:dd:c25:c25:d915:ab2e/1282c19:dd:d9:dd:c25:c25:d915:ab2e
482c19:dd:d9:dd:c25:c25:d915:ab2f/1282c19:dd:d9:dd:c25:c25:d915:ab2f
492c19:dd:d9:dd:c25:c25:d915:ab30/1282c19:dd:d9:dd:c25:c25:d915:ab30
502c19:dd:d9:dd:c25:c25:d915:ab31/1282c19:dd:d9:dd:c25:c25:d915:ab31
512c19:dd:d9:dd:c25:c25:d915:ab32/1282c19:dd:d9:dd:c25:c25:d915:ab32
522c19:dd:d9:dd:c25:c25:d915:ab33/1282c19:dd:d9:dd:c25:c25:d915:ab33
532c19:dd:d9:dd:c25:c25:d915:ab34/1282c19:dd:d9:dd:c25:c25:d915:ab34
542c19:dd:d9:dd:c25:c25:d915:ab35/1282c19:dd:d9:dd:c25:c25:d915:ab35
552c19:dd:d9:dd:c25:c25:d915:ab36/1282c19:dd:d9:dd:c25:c25:d915:ab36
562c19:dd:d9:dd:c25:c25:d915:ab37/1282c19:dd:d9:dd:c25:c25:d915:ab37
572c19:dd:d9:dd:c25:c25:d915:ab38/1282c19:dd:d9:dd:c25:c25:d915:ab38
582c19:dd:d9:dd:c25:c25:d915:ab39/1282c19:dd:d9:dd:c25:c25:d915:ab39
592c19:dd:d9:dd:c25:c25:d915:ab3a/1282c19:dd:d9:dd:c25:c25:d915:ab3a
602c19:dd:d9:dd:c25:c25:d915:ab3b/1282c19:dd:d9:dd:c25:c25:d915:ab3b
612c19:dd:d9:dd:c25:c25:d915:ab3c/1282c19:dd:d9:dd:c25:c25:d915:ab3c
622c19:dd:d9:dd:c25:c25:d915:ab3d/1282c19:dd:d9:dd:c25:c25:d915:ab3d
632c19:dd:d9:dd:c25:c25:d915:ab3e/1282c19:dd:d9:dd:c25:c25:d915:ab3e
642c19:dd:d9:dd:c25:c25:d915:ab3f/1282c19:dd:d9:dd:c25:c25:d915:ab3f
652c19:dd:d9:dd:c25:c25:d915:ab40/1282c19:dd:d9:dd:c25:c25:d915:ab40
662c19:dd:d9:dd:c25:c25:d915:ab41/1282c19:dd:d9:dd:c25:c25:d915:ab41
672c19:dd:d9:dd:c25:c25:d915:ab42/1282c19:dd:d9:dd:c25:c25:d915:ab42
682c19:dd:d9:dd:c25:c25:d915:ab43/1282c19:dd:d9:dd:c25:c25:d915:ab43
692c19:dd:d9:dd:c25:c25:d915:ab44/1282c19:dd:d9:dd:c25:c25:d915:ab44
702c19:dd:d9:dd:c25:c25:d915:ab45/1282c19:dd:d9:dd:c25:c25:d915:ab45
712c19:dd:d9:dd:c25:c25:d915:ab46/1282c19:dd:d9:dd:c25:c25:d915:ab46
722c19:dd:d9:dd:c25:c25:d915:ab47/1282c19:dd:d9:dd:c25:c25:d915:ab47
732c19:dd:d9:dd:c25:c25:d915:ab48/1282c19:dd:d9:dd:c25:c25:d915:ab48
742c19:dd:d9:dd:c25:c25:d915:ab49/1282c19:dd:d9:dd:c25:c25:d915:ab49
752c19:dd:d9:dd:c25:c25:d915:ab4a/1282c19:dd:d9:dd:c25:c25:d915:ab4a
762c19:dd:d9:dd:c25:c25:d915:ab4b/1282c19:dd:d9:dd:c25:c25:d915:ab4b
772c19:dd:d9:dd:c25:c25:d915:ab4c/1282c19:dd:d9:dd:c25:c25:d915:ab4c
782c19:dd:d9:dd:c25:c25:d915:ab4d/1282c19:dd:d9:dd:c25:c25:d915:ab4d
792c19:dd:d9:dd:c25:c25:d915:ab4e/1282c19:dd:d9:dd:c25:c25:d915:ab4e
802c19:dd:d9:dd:c25:c25:d915:ab4f/1282c19:dd:d9:dd:c25:c25:d915:ab4f
812c19:dd:d9:dd:c25:c25:d915:ab50/1282c19:dd:d9:dd:c25:c25:d915:ab50
822c19:dd:d9:dd:c25:c25:d915:ab51/1282c19:dd:d9:dd:c25:c25:d915:ab51
832c19:dd:d9:dd:c25:c25:d915:ab52/1282c19:dd:d9:dd:c25:c25:d915:ab52
842c19:dd:d9:dd:c25:c25:d915:ab53/1282c19:dd:d9:dd:c25:c25:d915:ab53
852c19:dd:d9:dd:c25:c25:d915:ab54/1282c19:dd:d9:dd:c25:c25:d915:ab54
862c19:dd:d9:dd:c25:c25:d915:ab55/1282c19:dd:d9:dd:c25:c25:d915:ab55
872c19:dd:d9:dd:c25:c25:d915:ab56/1282c19:dd:d9:dd:c25:c25:d915:ab56
882c19:dd:d9:dd:c25:c25:d915:ab57/1282c19:dd:d9:dd:c25:c25:d915:ab57
892c19:dd:d9:dd:c25:c25:d915:ab58/1282c19:dd:d9:dd:c25:c25:d915:ab58
902c19:dd:d9:dd:c25:c25:d915:ab59/1282c19:dd:d9:dd:c25:c25:d915:ab59
912c19:dd:d9:dd:c25:c25:d915:ab5a/1282c19:dd:d9:dd:c25:c25:d915:ab5a
922c19:dd:d9:dd:c25:c25:d915:ab5b/1282c19:dd:d9:dd:c25:c25:d915:ab5b
932c19:dd:d9:dd:c25:c25:d915:ab5c/1282c19:dd:d9:dd:c25:c25:d915:ab5c
942c19:dd:d9:dd:c25:c25:d915:ab5d/1282c19:dd:d9:dd:c25:c25:d915:ab5d
952c19:dd:d9:dd:c25:c25:d915:ab5e/1282c19:dd:d9:dd:c25:c25:d915:ab5e
962c19:dd:d9:dd:c25:c25:d915:ab5f/1282c19:dd:d9:dd:c25:c25:d915:ab5f
972c19:dd:d9:dd:c25:c25:d915:ab60/1282c19:dd:d9:dd:c25:c25:d915:ab60
982c19:dd:d9:dd:c25:c25:d915:ab61/1282c19:dd:d9:dd:c25:c25:d915:ab61
992c19:dd:d9:dd:c25:c25:d915:ab62/1282c19:dd:d9:dd:c25:c25:d915:ab62
1002c19:dd:d9:dd:c25:c25:d915:ab63/1282c19:dd:d9:dd:c25:c25:d915:ab63
1012c19:dd:d9:dd:c25:c25:d915:ab64/1282c19:dd:d9:dd:c25:c25:d915:ab64
1022c19:dd:d9:dd:c25:c25:d915:ab65/1282c19:dd:d9:dd:c25:c25:d915:ab65
1032c19:dd:d9:dd:c25:c25:d915:ab66/1282c19:dd:d9:dd:c25:c25:d915:ab66
1042c19:dd:d9:dd:c25:c25:d915:ab67/1282c19:dd:d9:dd:c25:c25:d915:ab67
1052c19:dd:d9:dd:c25:c25:d915:ab68/1282c19:dd:d9:dd:c25:c25:d915:ab68
1062c19:dd:d9:dd:c25:c25:d915:ab69/1282c19:dd:d9:dd:c25:c25:d915:ab69
1072c19:dd:d9:dd:c25:c25:d915:ab6a/1282c19:dd:d9:dd:c25:c25:d915:ab6a
1082c19:dd:d9:dd:c25:c25:d915:ab6b/1282c19:dd:d9:dd:c25:c25:d915:ab6b
1092c19:dd:d9:dd:c25:c25:d915:ab6c/1282c19:dd:d9:dd:c25:c25:d915:ab6c
1102c19:dd:d9:dd:c25:c25:d915:ab6d/1282c19:dd:d9:dd:c25:c25:d915:ab6d
1112c19:dd:d9:dd:c25:c25:d915:ab6e/1282c19:dd:d9:dd:c25:c25:d915:ab6e
1122c19:dd:d9:dd:c25:c25:d915:ab6f/1282c19:dd:d9:dd:c25:c25:d915:ab6f
1132c19:dd:d9:dd:c25:c25:d915:ab70/1282c19:dd:d9:dd:c25:c25:d915:ab70
1142c19:dd:d9:dd:c25:c25:d915:ab71/1282c19:dd:d9:dd:c25:c25:d915:ab71
1152c19:dd:d9:dd:c25:c25:d915:ab72/1282c19:dd:d9:dd:c25:c25:d915:ab72
1162c19:dd:d9:dd:c25:c25:d915:ab73/1282c19:dd:d9:dd:c25:c25:d915:ab73
1172c19:dd:d9:dd:c25:c25:d915:ab74/1282c19:dd:d9:dd:c25:c25:d915:ab74
1182c19:dd:d9:dd:c25:c25:d915:ab75/1282c19:dd:d9:dd:c25:c25:d915:ab75
1192c19:dd:d9:dd:c25:c25:d915:ab76/1282c19:dd:d9:dd:c25:c25:d915:ab76
1202c19:dd:d9:dd:c25:c25:d915:ab77/1282c19:dd:d9:dd:c25:c25:d915:ab77
1212c19:dd:d9:dd:c25:c25:d915:ab78/1282c19:dd:d9:dd:c25:c25:d915:ab78
1222c19:dd:d9:dd:c25:c25:d915:ab79/1282c19:dd:d9:dd:c25:c25:d915:ab79
1232c19:dd:d9:dd:c25:c25:d915:ab7a/1282c19:dd:d9:dd:c25:c25:d915:ab7a
1242c19:dd:d9:dd:c25:c25:d915:ab7b/1282c19:dd:d9:dd:c25:c25:d915:ab7b
1252c19:dd:d9:dd:c25:c25:d915:ab7c/1282c19:dd:d9:dd:c25:c25:d915:ab7c
1262c19:dd:d9:dd:c25:c25:d915:ab7d/1282c19:dd:d9:dd:c25:c25:d915:ab7d
1272c19:dd:d9:dd:c25:c25:d915:ab7e/1282c19:dd:d9:dd:c25:c25:d915:ab7e
1282c19:dd:d9:dd:c25:c25:d915:ab7f/1282c19:dd:d9:dd:c25:c25:d915:ab7f
1292c19:dd:d9:dd:c25:c25:d915:ab80/1282c19:dd:d9:dd:c25:c25:d915:ab80
1302c19:dd:d9:dd:c25:c25:d915:ab81/1282c19:dd:d9:dd:c25:c25:d915:ab81
1312c19:dd:d9:dd:c25:c25:d915:ab82/1282c19:dd:d9:dd:c25:c25:d915:ab82
1322c19:dd:d9:dd:c25:c25:d915:ab83/1282c19:dd:d9:dd:c25:c25:d915:ab83
1332c19:dd:d9:dd:c25:c25:d915:ab84/1282c19:dd:d9:dd:c25:c25:d915:ab84
1342c19:dd:d9:dd:c25:c25:d915:ab85/1282c19:dd:d9:dd:c25:c25:d915:ab85
1352c19:dd:d9:dd:c25:c25:d915:ab86/1282c19:dd:d9:dd:c25:c25:d915:ab86
1362c19:dd:d9:dd:c25:c25:d915:ab87/1282c19:dd:d9:dd:c25:c25:d915:ab87
1372c19:dd:d9:dd:c25:c25:d915:ab88/1282c19:dd:d9:dd:c25:c25:d915:ab88
1382c19:dd:d9:dd:c25:c25:d915:ab89/1282c19:dd:d9:dd:c25:c25:d915:ab89
1392c19:dd:d9:dd:c25:c25:d915:ab8a/1282c19:dd:d9:dd:c25:c25:d915:ab8a
1402c19:dd:d9:dd:c25:c25:d915:ab8b/1282c19:dd:d9:dd:c25:c25:d915:ab8b
1412c19:dd:d9:dd:c25:c25:d915:ab8c/1282c19:dd:d9:dd:c25:c25:d915:ab8c
1422c19:dd:d9:dd:c25:c25:d915:ab8d/1282c19:dd:d9:dd:c25:c25:d915:ab8d
1432c19:dd:d9:dd:c25:c25:d915:ab8e/1282c19:dd:d9:dd:c25:c25:d915:ab8e
1442c19:dd:d9:dd:c25:c25:d915:ab8f/1282c19:dd:d9:dd:c25:c25:d915:ab8f
1452c19:dd:d9:dd:c25:c25:d915:ab90/1282c19:dd:d9:dd:c25:c25:d915:ab90
1462c19:dd:d9:dd:c25:c25:d915:ab91/1282c19:dd:d9:dd:c25:c25:d915:ab91
1472c19:dd:d9:dd:c25:c25:d915:ab92/1282c19:dd:d9:dd:c25:c25:d915:ab92
1482c19:dd:d9:dd:c25:c25:d915:ab93/1282c19:dd:d9:dd:c25:c25:d915:ab93
1492c19:dd:d9:dd:c25:c25:d915:ab94/1282c19:dd:d9:dd:c25:c25:d915:ab94
1502c19:dd:d9:dd:c25:c25:d915:ab95/1282c19:dd:d9:dd:c25:c25:d915:ab95
1512c19:dd:d9:dd:c25:c25:d915:ab96/1282c19:dd:d9:dd:c25:c25:d915:ab96
1522c19:dd:d9:dd:c25:c25:d915:ab97/1282c19:dd:d9:dd:c25:c25:d915:ab97
1532c19:dd:d9:dd:c25:c25:d915:ab98/1282c19:dd:d9:dd:c25:c25:d915:ab98
1542c19:dd:d9:dd:c25:c25:d915:ab99/1282c19:dd:d9:dd:c25:c25:d915:ab99
1552c19:dd:d9:dd:c25:c25:d915:ab9a/1282c19:dd:d9:dd:c25:c25:d915:ab9a
1562c19:dd:d9:dd:c25:c25:d915:ab9b/1282c19:dd:d9:dd:c25:c25:d915:ab9b
1572c19:dd:d9:dd:c25:c25:d915:ab9c/1282c19:dd:d9:dd:c25:c25:d915:ab9c
1582c19:dd:d9:dd:c25:c25:d915:ab9d/1282c19:dd:d9:dd:c25:c25:d915:ab9d
1592c19:dd:d9:dd:c25:c25:d915:ab9e/1282c19:dd:d9:dd:c25:c25:d915:ab9e
1602c19:dd:d9:dd:c25:c25:d915:ab9f/1282c19:dd:d9:dd:c25:c25:d915:ab9f
1612c19:dd:d9:dd:c25:c25:d915:aba0/1282c19:dd:d9:dd:c25:c25:d915:aba0
1622c19:dd:d9:dd:c25:c25:d915:aba1/1282c19:dd:d9:dd:c25:c25:d915:aba1
1632c19:dd:d9:dd:c25:c25:d915:aba2/1282c19:dd:d9:dd:c25:c25:d915:aba2
1642c19:dd:d9:dd:c25:c25:d915:aba3/1282c19:dd:d9:dd:c25:c25:d915:aba3
1652c19:dd:d9:dd:c25:c25:d915:aba4/1282c19:dd:d9:dd:c25:c25:d915:aba4
1662c19:dd:d9:dd:c25:c25:d915:aba5/1282c19:dd:d9:dd:c25:c25:d915:aba5
1672c19:dd:d9:dd:c25:c25:d915:aba6/1282c19:dd:d9:dd:c25:c25:d915:aba6
1682c19:dd:d9:dd:c25:c25:d915:aba7/1282c19:dd:d9:dd:c25:c25:d915:aba7
1692c19:dd:d9:dd:c25:c25:d915:aba8/1282c19:dd:d9:dd:c25:c25:d915:aba8
1702c19:dd:d9:dd:c25:c25:d915:aba9/1282c19:dd:d9:dd:c25:c25:d915:aba9
1712c19:dd:d9:dd:c25:c25:d915:abaa/1282c19:dd:d9:dd:c25:c25:d915:abaa
1722c19:dd:d9:dd:c25:c25:d915:abab/1282c19:dd:d9:dd:c25:c25:d915:abab
1732c19:dd:d9:dd:c25:c25:d915:abac/1282c19:dd:d9:dd:c25:c25:d915:abac
1742c19:dd:d9:dd:c25:c25:d915:abad/1282c19:dd:d9:dd:c25:c25:d915:abad
1752c19:dd:d9:dd:c25:c25:d915:abae/1282c19:dd:d9:dd:c25:c25:d915:abae
1762c19:dd:d9:dd:c25:c25:d915:abaf/1282c19:dd:d9:dd:c25:c25:d915:abaf
1772c19:dd:d9:dd:c25:c25:d915:abb0/1282c19:dd:d9:dd:c25:c25:d915:abb0
1782c19:dd:d9:dd:c25:c25:d915:abb1/1282c19:dd:d9:dd:c25:c25:d915:abb1
1792c19:dd:d9:dd:c25:c25:d915:abb2/1282c19:dd:d9:dd:c25:c25:d915:abb2
1802c19:dd:d9:dd:c25:c25:d915:abb3/1282c19:dd:d9:dd:c25:c25:d915:abb3
1812c19:dd:d9:dd:c25:c25:d915:abb4/1282c19:dd:d9:dd:c25:c25:d915:abb4
1822c19:dd:d9:dd:c25:c25:d915:abb5/1282c19:dd:d9:dd:c25:c25:d915:abb5
1832c19:dd:d9:dd:c25:c25:d915:abb6/1282c19:dd:d9:dd:c25:c25:d915:abb6
1842c19:dd:d9:dd:c25:c25:d915:abb7/1282c19:dd:d9:dd:c25:c25:d915:abb7
1852c19:dd:d9:dd:c25:c25:d915:abb8/1282c19:dd:d9:dd:c25:c25:d915:abb8
1862c19:dd:d9:dd:c25:c25:d915:abb9/1282c19:dd:d9:dd:c25:c25:d915:abb9
1872c19:dd:d9:dd:c25:c25:d915:abba/1282c19:dd:d9:dd:c25:c25:d915:abba
1882c19:dd:d9:dd:c25:c25:d915:abbb/1282c19:dd:d9:dd:c25:c25:d915:abbb
1892c19:dd:d9:dd:c25:c25:d915:abbc/1282c19:dd:d9:dd:c25:c25:d915:abbc
1902c19:dd:d9:dd:c25:c25:d915:abbd/1282c19:dd:d9:dd:c25:c25:d915:abbd
1912c19:dd:d9:dd:c25:c25:d915:abbe/1282c19:dd:d9:dd:c25:c25:d915:abbe
1922c19:dd:d9:dd:c25:c25:d915:abbf/1282c19:dd:d9:dd:c25:c25:d915:abbf
1932c19:dd:d9:dd:c25:c25:d915:abc0/1282c19:dd:d9:dd:c25:c25:d915:abc0
1942c19:dd:d9:dd:c25:c25:d915:abc1/1282c19:dd:d9:dd:c25:c25:d915:abc1
1952c19:dd:d9:dd:c25:c25:d915:abc2/1282c19:dd:d9:dd:c25:c25:d915:abc2
1962c19:dd:d9:dd:c25:c25:d915:abc3/1282c19:dd:d9:dd:c25:c25:d915:abc3
1972c19:dd:d9:dd:c25:c25:d915:abc4/1282c19:dd:d9:dd:c25:c25:d915:abc4
1982c19:dd:d9:dd:c25:c25:d915:abc5/1282c19:dd:d9:dd:c25:c25:d915:abc5
1992c19:dd:d9:dd:c25:c25:d915:abc6/1282c19:dd:d9:dd:c25:c25:d915:abc6
2002c19:dd:d9:dd:c25:c25:d915:abc7/1282c19:dd:d9:dd:c25:c25:d915:abc7
2012c19:dd:d9:dd:c25:c25:d915:abc8/1282c19:dd:d9:dd:c25:c25:d915:abc8
2022c19:dd:d9:dd:c25:c25:d915:abc9/1282c19:dd:d9:dd:c25:c25:d915:abc9
2032c19:dd:d9:dd:c25:c25:d915:abca/1282c19:dd:d9:dd:c25:c25:d915:abca
2042c19:dd:d9:dd:c25:c25:d915:abcb/1282c19:dd:d9:dd:c25:c25:d915:abcb
2052c19:dd:d9:dd:c25:c25:d915:abcc/1282c19:dd:d9:dd:c25:c25:d915:abcc
2062c19:dd:d9:dd:c25:c25:d915:abcd/1282c19:dd:d9:dd:c25:c25:d915:abcd
2072c19:dd:d9:dd:c25:c25:d915:abce/1282c19:dd:d9:dd:c25:c25:d915:abce
2082c19:dd:d9:dd:c25:c25:d915:abcf/1282c19:dd:d9:dd:c25:c25:d915:abcf
2092c19:dd:d9:dd:c25:c25:d915:abd0/1282c19:dd:d9:dd:c25:c25:d915:abd0
2102c19:dd:d9:dd:c25:c25:d915:abd1/1282c19:dd:d9:dd:c25:c25:d915:abd1
2112c19:dd:d9:dd:c25:c25:d915:abd2/1282c19:dd:d9:dd:c25:c25:d915:abd2
2122c19:dd:d9:dd:c25:c25:d915:abd3/1282c19:dd:d9:dd:c25:c25:d915:abd3
2132c19:dd:d9:dd:c25:c25:d915:abd4/1282c19:dd:d9:dd:c25:c25:d915:abd4
2142c19:dd:d9:dd:c25:c25:d915:abd5/1282c19:dd:d9:dd:c25:c25:d915:abd5
2152c19:dd:d9:dd:c25:c25:d915:abd6/1282c19:dd:d9:dd:c25:c25:d915:abd6
2162c19:dd:d9:dd:c25:c25:d915:abd7/1282c19:dd:d9:dd:c25:c25:d915:abd7
2172c19:dd:d9:dd:c25:c25:d915:abd8/1282c19:dd:d9:dd:c25:c25:d915:abd8
2182c19:dd:d9:dd:c25:c25:d915:abd9/1282c19:dd:d9:dd:c25:c25:d915:abd9
2192c19:dd:d9:dd:c25:c25:d915:abda/1282c19:dd:d9:dd:c25:c25:d915:abda
2202c19:dd:d9:dd:c25:c25:d915:abdb/1282c19:dd:d9:dd:c25:c25:d915:abdb
2212c19:dd:d9:dd:c25:c25:d915:abdc/1282c19:dd:d9:dd:c25:c25:d915:abdc
2222c19:dd:d9:dd:c25:c25:d915:abdd/1282c19:dd:d9:dd:c25:c25:d915:abdd
2232c19:dd:d9:dd:c25:c25:d915:abde/1282c19:dd:d9:dd:c25:c25:d915:abde
2242c19:dd:d9:dd:c25:c25:d915:abdf/1282c19:dd:d9:dd:c25:c25:d915:abdf
2252c19:dd:d9:dd:c25:c25:d915:abe0/1282c19:dd:d9:dd:c25:c25:d915:abe0
2262c19:dd:d9:dd:c25:c25:d915:abe1/1282c19:dd:d9:dd:c25:c25:d915:abe1
2272c19:dd:d9:dd:c25:c25:d915:abe2/1282c19:dd:d9:dd:c25:c25:d915:abe2
2282c19:dd:d9:dd:c25:c25:d915:abe3/1282c19:dd:d9:dd:c25:c25:d915:abe3
2292c19:dd:d9:dd:c25:c25:d915:abe4/1282c19:dd:d9:dd:c25:c25:d915:abe4
2302c19:dd:d9:dd:c25:c25:d915:abe5/1282c19:dd:d9:dd:c25:c25:d915:abe5
2312c19:dd:d9:dd:c25:c25:d915:abe6/1282c19:dd:d9:dd:c25:c25:d915:abe6
2322c19:dd:d9:dd:c25:c25:d915:abe7/1282c19:dd:d9:dd:c25:c25:d915:abe7
2332c19:dd:d9:dd:c25:c25:d915:abe8/1282c19:dd:d9:dd:c25:c25:d915:abe8
2342c19:dd:d9:dd:c25:c25:d915:abe9/1282c19:dd:d9:dd:c25:c25:d915:abe9
2352c19:dd:d9:dd:c25:c25:d915:abea/1282c19:dd:d9:dd:c25:c25:d915:abea
2362c19:dd:d9:dd:c25:c25:d915:abeb/1282c19:dd:d9:dd:c25:c25:d915:abeb
2372c19:dd:d9:dd:c25:c25:d915:abec/1282c19:dd:d9:dd:c25:c25:d915:abec
2382c19:dd:d9:dd:c25:c25:d915:abed/1282c19:dd:d9:dd:c25:c25:d915:abed
2392c19:dd:d9:dd:c25:c25:d915:abee/1282c19:dd:d9:dd:c25:c25:d915:abee
2402c19:dd:d9:dd:c25:c25:d915:abef/1282c19:dd:d9:dd:c25:c25:d915:abef
2412c19:dd:d9:dd:c25:c25:d915:abf0/1282c19:dd:d9:dd:c25:c25:d915:abf0
2422c19:dd:d9:dd:c25:c25:d915:abf1/1282c19:dd:d9:dd:c25:c25:d915:abf1
2432c19:dd:d9:dd:c25:c25:d915:abf2/1282c19:dd:d9:dd:c25:c25:d915:abf2
2442c19:dd:d9:dd:c25:c25:d915:abf3/1282c19:dd:d9:dd:c25:c25:d915:abf3
2452c19:dd:d9:dd:c25:c25:d915:abf4/1282c19:dd:d9:dd:c25:c25:d915:abf4
2462c19:dd:d9:dd:c25:c25:d915:abf5/1282c19:dd:d9:dd:c25:c25:d915:abf5
2472c19:dd:d9:dd:c25:c25:d915:abf6/1282c19:dd:d9:dd:c25:c25:d915:abf6
2482c19:dd:d9:dd:c25:c25:d915:abf7/1282c19:dd:d9:dd:c25:c25:d915:abf7
2492c19:dd:d9:dd:c25:c25:d915:abf8/1282c19:dd:d9:dd:c25:c25:d915:abf8
2502c19:dd:d9:dd:c25:c25:d915:abf9/1282c19:dd:d9:dd:c25:c25:d915:abf9
2512c19:dd:d9:dd:c25:c25:d915:abfa/1282c19:dd:d9:dd:c25:c25:d915:abfa
2522c19:dd:d9:dd:c25:c25:d915:abfb/1282c19:dd:d9:dd:c25:c25:d915:abfb
2532c19:dd:d9:dd:c25:c25:d915:abfc/1282c19:dd:d9:dd:c25:c25:d915:abfc
2542c19:dd:d9:dd:c25:c25:d915:abfd/1282c19:dd:d9:dd:c25:c25:d915:abfd
2552c19:dd:d9:dd:c25:c25:d915:abfe/1282c19:dd:d9:dd:c25:c25:d915:abfe
2562c19:dd:d9:dd:c25:c25:d915:abff/1282c19:dd:d9:dd:c25:c25:d915:abff

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.