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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:c25a:d00a:fd00/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:fd00
Last address
2c19:dd:d9:dd:c25:c25a:d00a:fdff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:fd00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
d.f.a.0.0.d.a.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:c25a:d00a:fd00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:fd00/1282c19:dd:d9:dd:c25:c25a:d00a:fd00
22c19:dd:d9:dd:c25:c25a:d00a:fd01/1282c19:dd:d9:dd:c25:c25a:d00a:fd01
32c19:dd:d9:dd:c25:c25a:d00a:fd02/1282c19:dd:d9:dd:c25:c25a:d00a:fd02
42c19:dd:d9:dd:c25:c25a:d00a:fd03/1282c19:dd:d9:dd:c25:c25a:d00a:fd03
52c19:dd:d9:dd:c25:c25a:d00a:fd04/1282c19:dd:d9:dd:c25:c25a:d00a:fd04
62c19:dd:d9:dd:c25:c25a:d00a:fd05/1282c19:dd:d9:dd:c25:c25a:d00a:fd05
72c19:dd:d9:dd:c25:c25a:d00a:fd06/1282c19:dd:d9:dd:c25:c25a:d00a:fd06
82c19:dd:d9:dd:c25:c25a:d00a:fd07/1282c19:dd:d9:dd:c25:c25a:d00a:fd07
92c19:dd:d9:dd:c25:c25a:d00a:fd08/1282c19:dd:d9:dd:c25:c25a:d00a:fd08
102c19:dd:d9:dd:c25:c25a:d00a:fd09/1282c19:dd:d9:dd:c25:c25a:d00a:fd09
112c19:dd:d9:dd:c25:c25a:d00a:fd0a/1282c19:dd:d9:dd:c25:c25a:d00a:fd0a
122c19:dd:d9:dd:c25:c25a:d00a:fd0b/1282c19:dd:d9:dd:c25:c25a:d00a:fd0b
132c19:dd:d9:dd:c25:c25a:d00a:fd0c/1282c19:dd:d9:dd:c25:c25a:d00a:fd0c
142c19:dd:d9:dd:c25:c25a:d00a:fd0d/1282c19:dd:d9:dd:c25:c25a:d00a:fd0d
152c19:dd:d9:dd:c25:c25a:d00a:fd0e/1282c19:dd:d9:dd:c25:c25a:d00a:fd0e
162c19:dd:d9:dd:c25:c25a:d00a:fd0f/1282c19:dd:d9:dd:c25:c25a:d00a:fd0f
172c19:dd:d9:dd:c25:c25a:d00a:fd10/1282c19:dd:d9:dd:c25:c25a:d00a:fd10
182c19:dd:d9:dd:c25:c25a:d00a:fd11/1282c19:dd:d9:dd:c25:c25a:d00a:fd11
192c19:dd:d9:dd:c25:c25a:d00a:fd12/1282c19:dd:d9:dd:c25:c25a:d00a:fd12
202c19:dd:d9:dd:c25:c25a:d00a:fd13/1282c19:dd:d9:dd:c25:c25a:d00a:fd13
212c19:dd:d9:dd:c25:c25a:d00a:fd14/1282c19:dd:d9:dd:c25:c25a:d00a:fd14
222c19:dd:d9:dd:c25:c25a:d00a:fd15/1282c19:dd:d9:dd:c25:c25a:d00a:fd15
232c19:dd:d9:dd:c25:c25a:d00a:fd16/1282c19:dd:d9:dd:c25:c25a:d00a:fd16
242c19:dd:d9:dd:c25:c25a:d00a:fd17/1282c19:dd:d9:dd:c25:c25a:d00a:fd17
252c19:dd:d9:dd:c25:c25a:d00a:fd18/1282c19:dd:d9:dd:c25:c25a:d00a:fd18
262c19:dd:d9:dd:c25:c25a:d00a:fd19/1282c19:dd:d9:dd:c25:c25a:d00a:fd19
272c19:dd:d9:dd:c25:c25a:d00a:fd1a/1282c19:dd:d9:dd:c25:c25a:d00a:fd1a
282c19:dd:d9:dd:c25:c25a:d00a:fd1b/1282c19:dd:d9:dd:c25:c25a:d00a:fd1b
292c19:dd:d9:dd:c25:c25a:d00a:fd1c/1282c19:dd:d9:dd:c25:c25a:d00a:fd1c
302c19:dd:d9:dd:c25:c25a:d00a:fd1d/1282c19:dd:d9:dd:c25:c25a:d00a:fd1d
312c19:dd:d9:dd:c25:c25a:d00a:fd1e/1282c19:dd:d9:dd:c25:c25a:d00a:fd1e
322c19:dd:d9:dd:c25:c25a:d00a:fd1f/1282c19:dd:d9:dd:c25:c25a:d00a:fd1f
332c19:dd:d9:dd:c25:c25a:d00a:fd20/1282c19:dd:d9:dd:c25:c25a:d00a:fd20
342c19:dd:d9:dd:c25:c25a:d00a:fd21/1282c19:dd:d9:dd:c25:c25a:d00a:fd21
352c19:dd:d9:dd:c25:c25a:d00a:fd22/1282c19:dd:d9:dd:c25:c25a:d00a:fd22
362c19:dd:d9:dd:c25:c25a:d00a:fd23/1282c19:dd:d9:dd:c25:c25a:d00a:fd23
372c19:dd:d9:dd:c25:c25a:d00a:fd24/1282c19:dd:d9:dd:c25:c25a:d00a:fd24
382c19:dd:d9:dd:c25:c25a:d00a:fd25/1282c19:dd:d9:dd:c25:c25a:d00a:fd25
392c19:dd:d9:dd:c25:c25a:d00a:fd26/1282c19:dd:d9:dd:c25:c25a:d00a:fd26
402c19:dd:d9:dd:c25:c25a:d00a:fd27/1282c19:dd:d9:dd:c25:c25a:d00a:fd27
412c19:dd:d9:dd:c25:c25a:d00a:fd28/1282c19:dd:d9:dd:c25:c25a:d00a:fd28
422c19:dd:d9:dd:c25:c25a:d00a:fd29/1282c19:dd:d9:dd:c25:c25a:d00a:fd29
432c19:dd:d9:dd:c25:c25a:d00a:fd2a/1282c19:dd:d9:dd:c25:c25a:d00a:fd2a
442c19:dd:d9:dd:c25:c25a:d00a:fd2b/1282c19:dd:d9:dd:c25:c25a:d00a:fd2b
452c19:dd:d9:dd:c25:c25a:d00a:fd2c/1282c19:dd:d9:dd:c25:c25a:d00a:fd2c
462c19:dd:d9:dd:c25:c25a:d00a:fd2d/1282c19:dd:d9:dd:c25:c25a:d00a:fd2d
472c19:dd:d9:dd:c25:c25a:d00a:fd2e/1282c19:dd:d9:dd:c25:c25a:d00a:fd2e
482c19:dd:d9:dd:c25:c25a:d00a:fd2f/1282c19:dd:d9:dd:c25:c25a:d00a:fd2f
492c19:dd:d9:dd:c25:c25a:d00a:fd30/1282c19:dd:d9:dd:c25:c25a:d00a:fd30
502c19:dd:d9:dd:c25:c25a:d00a:fd31/1282c19:dd:d9:dd:c25:c25a:d00a:fd31
512c19:dd:d9:dd:c25:c25a:d00a:fd32/1282c19:dd:d9:dd:c25:c25a:d00a:fd32
522c19:dd:d9:dd:c25:c25a:d00a:fd33/1282c19:dd:d9:dd:c25:c25a:d00a:fd33
532c19:dd:d9:dd:c25:c25a:d00a:fd34/1282c19:dd:d9:dd:c25:c25a:d00a:fd34
542c19:dd:d9:dd:c25:c25a:d00a:fd35/1282c19:dd:d9:dd:c25:c25a:d00a:fd35
552c19:dd:d9:dd:c25:c25a:d00a:fd36/1282c19:dd:d9:dd:c25:c25a:d00a:fd36
562c19:dd:d9:dd:c25:c25a:d00a:fd37/1282c19:dd:d9:dd:c25:c25a:d00a:fd37
572c19:dd:d9:dd:c25:c25a:d00a:fd38/1282c19:dd:d9:dd:c25:c25a:d00a:fd38
582c19:dd:d9:dd:c25:c25a:d00a:fd39/1282c19:dd:d9:dd:c25:c25a:d00a:fd39
592c19:dd:d9:dd:c25:c25a:d00a:fd3a/1282c19:dd:d9:dd:c25:c25a:d00a:fd3a
602c19:dd:d9:dd:c25:c25a:d00a:fd3b/1282c19:dd:d9:dd:c25:c25a:d00a:fd3b
612c19:dd:d9:dd:c25:c25a:d00a:fd3c/1282c19:dd:d9:dd:c25:c25a:d00a:fd3c
622c19:dd:d9:dd:c25:c25a:d00a:fd3d/1282c19:dd:d9:dd:c25:c25a:d00a:fd3d
632c19:dd:d9:dd:c25:c25a:d00a:fd3e/1282c19:dd:d9:dd:c25:c25a:d00a:fd3e
642c19:dd:d9:dd:c25:c25a:d00a:fd3f/1282c19:dd:d9:dd:c25:c25a:d00a:fd3f
652c19:dd:d9:dd:c25:c25a:d00a:fd40/1282c19:dd:d9:dd:c25:c25a:d00a:fd40
662c19:dd:d9:dd:c25:c25a:d00a:fd41/1282c19:dd:d9:dd:c25:c25a:d00a:fd41
672c19:dd:d9:dd:c25:c25a:d00a:fd42/1282c19:dd:d9:dd:c25:c25a:d00a:fd42
682c19:dd:d9:dd:c25:c25a:d00a:fd43/1282c19:dd:d9:dd:c25:c25a:d00a:fd43
692c19:dd:d9:dd:c25:c25a:d00a:fd44/1282c19:dd:d9:dd:c25:c25a:d00a:fd44
702c19:dd:d9:dd:c25:c25a:d00a:fd45/1282c19:dd:d9:dd:c25:c25a:d00a:fd45
712c19:dd:d9:dd:c25:c25a:d00a:fd46/1282c19:dd:d9:dd:c25:c25a:d00a:fd46
722c19:dd:d9:dd:c25:c25a:d00a:fd47/1282c19:dd:d9:dd:c25:c25a:d00a:fd47
732c19:dd:d9:dd:c25:c25a:d00a:fd48/1282c19:dd:d9:dd:c25:c25a:d00a:fd48
742c19:dd:d9:dd:c25:c25a:d00a:fd49/1282c19:dd:d9:dd:c25:c25a:d00a:fd49
752c19:dd:d9:dd:c25:c25a:d00a:fd4a/1282c19:dd:d9:dd:c25:c25a:d00a:fd4a
762c19:dd:d9:dd:c25:c25a:d00a:fd4b/1282c19:dd:d9:dd:c25:c25a:d00a:fd4b
772c19:dd:d9:dd:c25:c25a:d00a:fd4c/1282c19:dd:d9:dd:c25:c25a:d00a:fd4c
782c19:dd:d9:dd:c25:c25a:d00a:fd4d/1282c19:dd:d9:dd:c25:c25a:d00a:fd4d
792c19:dd:d9:dd:c25:c25a:d00a:fd4e/1282c19:dd:d9:dd:c25:c25a:d00a:fd4e
802c19:dd:d9:dd:c25:c25a:d00a:fd4f/1282c19:dd:d9:dd:c25:c25a:d00a:fd4f
812c19:dd:d9:dd:c25:c25a:d00a:fd50/1282c19:dd:d9:dd:c25:c25a:d00a:fd50
822c19:dd:d9:dd:c25:c25a:d00a:fd51/1282c19:dd:d9:dd:c25:c25a:d00a:fd51
832c19:dd:d9:dd:c25:c25a:d00a:fd52/1282c19:dd:d9:dd:c25:c25a:d00a:fd52
842c19:dd:d9:dd:c25:c25a:d00a:fd53/1282c19:dd:d9:dd:c25:c25a:d00a:fd53
852c19:dd:d9:dd:c25:c25a:d00a:fd54/1282c19:dd:d9:dd:c25:c25a:d00a:fd54
862c19:dd:d9:dd:c25:c25a:d00a:fd55/1282c19:dd:d9:dd:c25:c25a:d00a:fd55
872c19:dd:d9:dd:c25:c25a:d00a:fd56/1282c19:dd:d9:dd:c25:c25a:d00a:fd56
882c19:dd:d9:dd:c25:c25a:d00a:fd57/1282c19:dd:d9:dd:c25:c25a:d00a:fd57
892c19:dd:d9:dd:c25:c25a:d00a:fd58/1282c19:dd:d9:dd:c25:c25a:d00a:fd58
902c19:dd:d9:dd:c25:c25a:d00a:fd59/1282c19:dd:d9:dd:c25:c25a:d00a:fd59
912c19:dd:d9:dd:c25:c25a:d00a:fd5a/1282c19:dd:d9:dd:c25:c25a:d00a:fd5a
922c19:dd:d9:dd:c25:c25a:d00a:fd5b/1282c19:dd:d9:dd:c25:c25a:d00a:fd5b
932c19:dd:d9:dd:c25:c25a:d00a:fd5c/1282c19:dd:d9:dd:c25:c25a:d00a:fd5c
942c19:dd:d9:dd:c25:c25a:d00a:fd5d/1282c19:dd:d9:dd:c25:c25a:d00a:fd5d
952c19:dd:d9:dd:c25:c25a:d00a:fd5e/1282c19:dd:d9:dd:c25:c25a:d00a:fd5e
962c19:dd:d9:dd:c25:c25a:d00a:fd5f/1282c19:dd:d9:dd:c25:c25a:d00a:fd5f
972c19:dd:d9:dd:c25:c25a:d00a:fd60/1282c19:dd:d9:dd:c25:c25a:d00a:fd60
982c19:dd:d9:dd:c25:c25a:d00a:fd61/1282c19:dd:d9:dd:c25:c25a:d00a:fd61
992c19:dd:d9:dd:c25:c25a:d00a:fd62/1282c19:dd:d9:dd:c25:c25a:d00a:fd62
1002c19:dd:d9:dd:c25:c25a:d00a:fd63/1282c19:dd:d9:dd:c25:c25a:d00a:fd63
1012c19:dd:d9:dd:c25:c25a:d00a:fd64/1282c19:dd:d9:dd:c25:c25a:d00a:fd64
1022c19:dd:d9:dd:c25:c25a:d00a:fd65/1282c19:dd:d9:dd:c25:c25a:d00a:fd65
1032c19:dd:d9:dd:c25:c25a:d00a:fd66/1282c19:dd:d9:dd:c25:c25a:d00a:fd66
1042c19:dd:d9:dd:c25:c25a:d00a:fd67/1282c19:dd:d9:dd:c25:c25a:d00a:fd67
1052c19:dd:d9:dd:c25:c25a:d00a:fd68/1282c19:dd:d9:dd:c25:c25a:d00a:fd68
1062c19:dd:d9:dd:c25:c25a:d00a:fd69/1282c19:dd:d9:dd:c25:c25a:d00a:fd69
1072c19:dd:d9:dd:c25:c25a:d00a:fd6a/1282c19:dd:d9:dd:c25:c25a:d00a:fd6a
1082c19:dd:d9:dd:c25:c25a:d00a:fd6b/1282c19:dd:d9:dd:c25:c25a:d00a:fd6b
1092c19:dd:d9:dd:c25:c25a:d00a:fd6c/1282c19:dd:d9:dd:c25:c25a:d00a:fd6c
1102c19:dd:d9:dd:c25:c25a:d00a:fd6d/1282c19:dd:d9:dd:c25:c25a:d00a:fd6d
1112c19:dd:d9:dd:c25:c25a:d00a:fd6e/1282c19:dd:d9:dd:c25:c25a:d00a:fd6e
1122c19:dd:d9:dd:c25:c25a:d00a:fd6f/1282c19:dd:d9:dd:c25:c25a:d00a:fd6f
1132c19:dd:d9:dd:c25:c25a:d00a:fd70/1282c19:dd:d9:dd:c25:c25a:d00a:fd70
1142c19:dd:d9:dd:c25:c25a:d00a:fd71/1282c19:dd:d9:dd:c25:c25a:d00a:fd71
1152c19:dd:d9:dd:c25:c25a:d00a:fd72/1282c19:dd:d9:dd:c25:c25a:d00a:fd72
1162c19:dd:d9:dd:c25:c25a:d00a:fd73/1282c19:dd:d9:dd:c25:c25a:d00a:fd73
1172c19:dd:d9:dd:c25:c25a:d00a:fd74/1282c19:dd:d9:dd:c25:c25a:d00a:fd74
1182c19:dd:d9:dd:c25:c25a:d00a:fd75/1282c19:dd:d9:dd:c25:c25a:d00a:fd75
1192c19:dd:d9:dd:c25:c25a:d00a:fd76/1282c19:dd:d9:dd:c25:c25a:d00a:fd76
1202c19:dd:d9:dd:c25:c25a:d00a:fd77/1282c19:dd:d9:dd:c25:c25a:d00a:fd77
1212c19:dd:d9:dd:c25:c25a:d00a:fd78/1282c19:dd:d9:dd:c25:c25a:d00a:fd78
1222c19:dd:d9:dd:c25:c25a:d00a:fd79/1282c19:dd:d9:dd:c25:c25a:d00a:fd79
1232c19:dd:d9:dd:c25:c25a:d00a:fd7a/1282c19:dd:d9:dd:c25:c25a:d00a:fd7a
1242c19:dd:d9:dd:c25:c25a:d00a:fd7b/1282c19:dd:d9:dd:c25:c25a:d00a:fd7b
1252c19:dd:d9:dd:c25:c25a:d00a:fd7c/1282c19:dd:d9:dd:c25:c25a:d00a:fd7c
1262c19:dd:d9:dd:c25:c25a:d00a:fd7d/1282c19:dd:d9:dd:c25:c25a:d00a:fd7d
1272c19:dd:d9:dd:c25:c25a:d00a:fd7e/1282c19:dd:d9:dd:c25:c25a:d00a:fd7e
1282c19:dd:d9:dd:c25:c25a:d00a:fd7f/1282c19:dd:d9:dd:c25:c25a:d00a:fd7f
1292c19:dd:d9:dd:c25:c25a:d00a:fd80/1282c19:dd:d9:dd:c25:c25a:d00a:fd80
1302c19:dd:d9:dd:c25:c25a:d00a:fd81/1282c19:dd:d9:dd:c25:c25a:d00a:fd81
1312c19:dd:d9:dd:c25:c25a:d00a:fd82/1282c19:dd:d9:dd:c25:c25a:d00a:fd82
1322c19:dd:d9:dd:c25:c25a:d00a:fd83/1282c19:dd:d9:dd:c25:c25a:d00a:fd83
1332c19:dd:d9:dd:c25:c25a:d00a:fd84/1282c19:dd:d9:dd:c25:c25a:d00a:fd84
1342c19:dd:d9:dd:c25:c25a:d00a:fd85/1282c19:dd:d9:dd:c25:c25a:d00a:fd85
1352c19:dd:d9:dd:c25:c25a:d00a:fd86/1282c19:dd:d9:dd:c25:c25a:d00a:fd86
1362c19:dd:d9:dd:c25:c25a:d00a:fd87/1282c19:dd:d9:dd:c25:c25a:d00a:fd87
1372c19:dd:d9:dd:c25:c25a:d00a:fd88/1282c19:dd:d9:dd:c25:c25a:d00a:fd88
1382c19:dd:d9:dd:c25:c25a:d00a:fd89/1282c19:dd:d9:dd:c25:c25a:d00a:fd89
1392c19:dd:d9:dd:c25:c25a:d00a:fd8a/1282c19:dd:d9:dd:c25:c25a:d00a:fd8a
1402c19:dd:d9:dd:c25:c25a:d00a:fd8b/1282c19:dd:d9:dd:c25:c25a:d00a:fd8b
1412c19:dd:d9:dd:c25:c25a:d00a:fd8c/1282c19:dd:d9:dd:c25:c25a:d00a:fd8c
1422c19:dd:d9:dd:c25:c25a:d00a:fd8d/1282c19:dd:d9:dd:c25:c25a:d00a:fd8d
1432c19:dd:d9:dd:c25:c25a:d00a:fd8e/1282c19:dd:d9:dd:c25:c25a:d00a:fd8e
1442c19:dd:d9:dd:c25:c25a:d00a:fd8f/1282c19:dd:d9:dd:c25:c25a:d00a:fd8f
1452c19:dd:d9:dd:c25:c25a:d00a:fd90/1282c19:dd:d9:dd:c25:c25a:d00a:fd90
1462c19:dd:d9:dd:c25:c25a:d00a:fd91/1282c19:dd:d9:dd:c25:c25a:d00a:fd91
1472c19:dd:d9:dd:c25:c25a:d00a:fd92/1282c19:dd:d9:dd:c25:c25a:d00a:fd92
1482c19:dd:d9:dd:c25:c25a:d00a:fd93/1282c19:dd:d9:dd:c25:c25a:d00a:fd93
1492c19:dd:d9:dd:c25:c25a:d00a:fd94/1282c19:dd:d9:dd:c25:c25a:d00a:fd94
1502c19:dd:d9:dd:c25:c25a:d00a:fd95/1282c19:dd:d9:dd:c25:c25a:d00a:fd95
1512c19:dd:d9:dd:c25:c25a:d00a:fd96/1282c19:dd:d9:dd:c25:c25a:d00a:fd96
1522c19:dd:d9:dd:c25:c25a:d00a:fd97/1282c19:dd:d9:dd:c25:c25a:d00a:fd97
1532c19:dd:d9:dd:c25:c25a:d00a:fd98/1282c19:dd:d9:dd:c25:c25a:d00a:fd98
1542c19:dd:d9:dd:c25:c25a:d00a:fd99/1282c19:dd:d9:dd:c25:c25a:d00a:fd99
1552c19:dd:d9:dd:c25:c25a:d00a:fd9a/1282c19:dd:d9:dd:c25:c25a:d00a:fd9a
1562c19:dd:d9:dd:c25:c25a:d00a:fd9b/1282c19:dd:d9:dd:c25:c25a:d00a:fd9b
1572c19:dd:d9:dd:c25:c25a:d00a:fd9c/1282c19:dd:d9:dd:c25:c25a:d00a:fd9c
1582c19:dd:d9:dd:c25:c25a:d00a:fd9d/1282c19:dd:d9:dd:c25:c25a:d00a:fd9d
1592c19:dd:d9:dd:c25:c25a:d00a:fd9e/1282c19:dd:d9:dd:c25:c25a:d00a:fd9e
1602c19:dd:d9:dd:c25:c25a:d00a:fd9f/1282c19:dd:d9:dd:c25:c25a:d00a:fd9f
1612c19:dd:d9:dd:c25:c25a:d00a:fda0/1282c19:dd:d9:dd:c25:c25a:d00a:fda0
1622c19:dd:d9:dd:c25:c25a:d00a:fda1/1282c19:dd:d9:dd:c25:c25a:d00a:fda1
1632c19:dd:d9:dd:c25:c25a:d00a:fda2/1282c19:dd:d9:dd:c25:c25a:d00a:fda2
1642c19:dd:d9:dd:c25:c25a:d00a:fda3/1282c19:dd:d9:dd:c25:c25a:d00a:fda3
1652c19:dd:d9:dd:c25:c25a:d00a:fda4/1282c19:dd:d9:dd:c25:c25a:d00a:fda4
1662c19:dd:d9:dd:c25:c25a:d00a:fda5/1282c19:dd:d9:dd:c25:c25a:d00a:fda5
1672c19:dd:d9:dd:c25:c25a:d00a:fda6/1282c19:dd:d9:dd:c25:c25a:d00a:fda6
1682c19:dd:d9:dd:c25:c25a:d00a:fda7/1282c19:dd:d9:dd:c25:c25a:d00a:fda7
1692c19:dd:d9:dd:c25:c25a:d00a:fda8/1282c19:dd:d9:dd:c25:c25a:d00a:fda8
1702c19:dd:d9:dd:c25:c25a:d00a:fda9/1282c19:dd:d9:dd:c25:c25a:d00a:fda9
1712c19:dd:d9:dd:c25:c25a:d00a:fdaa/1282c19:dd:d9:dd:c25:c25a:d00a:fdaa
1722c19:dd:d9:dd:c25:c25a:d00a:fdab/1282c19:dd:d9:dd:c25:c25a:d00a:fdab
1732c19:dd:d9:dd:c25:c25a:d00a:fdac/1282c19:dd:d9:dd:c25:c25a:d00a:fdac
1742c19:dd:d9:dd:c25:c25a:d00a:fdad/1282c19:dd:d9:dd:c25:c25a:d00a:fdad
1752c19:dd:d9:dd:c25:c25a:d00a:fdae/1282c19:dd:d9:dd:c25:c25a:d00a:fdae
1762c19:dd:d9:dd:c25:c25a:d00a:fdaf/1282c19:dd:d9:dd:c25:c25a:d00a:fdaf
1772c19:dd:d9:dd:c25:c25a:d00a:fdb0/1282c19:dd:d9:dd:c25:c25a:d00a:fdb0
1782c19:dd:d9:dd:c25:c25a:d00a:fdb1/1282c19:dd:d9:dd:c25:c25a:d00a:fdb1
1792c19:dd:d9:dd:c25:c25a:d00a:fdb2/1282c19:dd:d9:dd:c25:c25a:d00a:fdb2
1802c19:dd:d9:dd:c25:c25a:d00a:fdb3/1282c19:dd:d9:dd:c25:c25a:d00a:fdb3
1812c19:dd:d9:dd:c25:c25a:d00a:fdb4/1282c19:dd:d9:dd:c25:c25a:d00a:fdb4
1822c19:dd:d9:dd:c25:c25a:d00a:fdb5/1282c19:dd:d9:dd:c25:c25a:d00a:fdb5
1832c19:dd:d9:dd:c25:c25a:d00a:fdb6/1282c19:dd:d9:dd:c25:c25a:d00a:fdb6
1842c19:dd:d9:dd:c25:c25a:d00a:fdb7/1282c19:dd:d9:dd:c25:c25a:d00a:fdb7
1852c19:dd:d9:dd:c25:c25a:d00a:fdb8/1282c19:dd:d9:dd:c25:c25a:d00a:fdb8
1862c19:dd:d9:dd:c25:c25a:d00a:fdb9/1282c19:dd:d9:dd:c25:c25a:d00a:fdb9
1872c19:dd:d9:dd:c25:c25a:d00a:fdba/1282c19:dd:d9:dd:c25:c25a:d00a:fdba
1882c19:dd:d9:dd:c25:c25a:d00a:fdbb/1282c19:dd:d9:dd:c25:c25a:d00a:fdbb
1892c19:dd:d9:dd:c25:c25a:d00a:fdbc/1282c19:dd:d9:dd:c25:c25a:d00a:fdbc
1902c19:dd:d9:dd:c25:c25a:d00a:fdbd/1282c19:dd:d9:dd:c25:c25a:d00a:fdbd
1912c19:dd:d9:dd:c25:c25a:d00a:fdbe/1282c19:dd:d9:dd:c25:c25a:d00a:fdbe
1922c19:dd:d9:dd:c25:c25a:d00a:fdbf/1282c19:dd:d9:dd:c25:c25a:d00a:fdbf
1932c19:dd:d9:dd:c25:c25a:d00a:fdc0/1282c19:dd:d9:dd:c25:c25a:d00a:fdc0
1942c19:dd:d9:dd:c25:c25a:d00a:fdc1/1282c19:dd:d9:dd:c25:c25a:d00a:fdc1
1952c19:dd:d9:dd:c25:c25a:d00a:fdc2/1282c19:dd:d9:dd:c25:c25a:d00a:fdc2
1962c19:dd:d9:dd:c25:c25a:d00a:fdc3/1282c19:dd:d9:dd:c25:c25a:d00a:fdc3
1972c19:dd:d9:dd:c25:c25a:d00a:fdc4/1282c19:dd:d9:dd:c25:c25a:d00a:fdc4
1982c19:dd:d9:dd:c25:c25a:d00a:fdc5/1282c19:dd:d9:dd:c25:c25a:d00a:fdc5
1992c19:dd:d9:dd:c25:c25a:d00a:fdc6/1282c19:dd:d9:dd:c25:c25a:d00a:fdc6
2002c19:dd:d9:dd:c25:c25a:d00a:fdc7/1282c19:dd:d9:dd:c25:c25a:d00a:fdc7
2012c19:dd:d9:dd:c25:c25a:d00a:fdc8/1282c19:dd:d9:dd:c25:c25a:d00a:fdc8
2022c19:dd:d9:dd:c25:c25a:d00a:fdc9/1282c19:dd:d9:dd:c25:c25a:d00a:fdc9
2032c19:dd:d9:dd:c25:c25a:d00a:fdca/1282c19:dd:d9:dd:c25:c25a:d00a:fdca
2042c19:dd:d9:dd:c25:c25a:d00a:fdcb/1282c19:dd:d9:dd:c25:c25a:d00a:fdcb
2052c19:dd:d9:dd:c25:c25a:d00a:fdcc/1282c19:dd:d9:dd:c25:c25a:d00a:fdcc
2062c19:dd:d9:dd:c25:c25a:d00a:fdcd/1282c19:dd:d9:dd:c25:c25a:d00a:fdcd
2072c19:dd:d9:dd:c25:c25a:d00a:fdce/1282c19:dd:d9:dd:c25:c25a:d00a:fdce
2082c19:dd:d9:dd:c25:c25a:d00a:fdcf/1282c19:dd:d9:dd:c25:c25a:d00a:fdcf
2092c19:dd:d9:dd:c25:c25a:d00a:fdd0/1282c19:dd:d9:dd:c25:c25a:d00a:fdd0
2102c19:dd:d9:dd:c25:c25a:d00a:fdd1/1282c19:dd:d9:dd:c25:c25a:d00a:fdd1
2112c19:dd:d9:dd:c25:c25a:d00a:fdd2/1282c19:dd:d9:dd:c25:c25a:d00a:fdd2
2122c19:dd:d9:dd:c25:c25a:d00a:fdd3/1282c19:dd:d9:dd:c25:c25a:d00a:fdd3
2132c19:dd:d9:dd:c25:c25a:d00a:fdd4/1282c19:dd:d9:dd:c25:c25a:d00a:fdd4
2142c19:dd:d9:dd:c25:c25a:d00a:fdd5/1282c19:dd:d9:dd:c25:c25a:d00a:fdd5
2152c19:dd:d9:dd:c25:c25a:d00a:fdd6/1282c19:dd:d9:dd:c25:c25a:d00a:fdd6
2162c19:dd:d9:dd:c25:c25a:d00a:fdd7/1282c19:dd:d9:dd:c25:c25a:d00a:fdd7
2172c19:dd:d9:dd:c25:c25a:d00a:fdd8/1282c19:dd:d9:dd:c25:c25a:d00a:fdd8
2182c19:dd:d9:dd:c25:c25a:d00a:fdd9/1282c19:dd:d9:dd:c25:c25a:d00a:fdd9
2192c19:dd:d9:dd:c25:c25a:d00a:fdda/1282c19:dd:d9:dd:c25:c25a:d00a:fdda
2202c19:dd:d9:dd:c25:c25a:d00a:fddb/1282c19:dd:d9:dd:c25:c25a:d00a:fddb
2212c19:dd:d9:dd:c25:c25a:d00a:fddc/1282c19:dd:d9:dd:c25:c25a:d00a:fddc
2222c19:dd:d9:dd:c25:c25a:d00a:fddd/1282c19:dd:d9:dd:c25:c25a:d00a:fddd
2232c19:dd:d9:dd:c25:c25a:d00a:fdde/1282c19:dd:d9:dd:c25:c25a:d00a:fdde
2242c19:dd:d9:dd:c25:c25a:d00a:fddf/1282c19:dd:d9:dd:c25:c25a:d00a:fddf
2252c19:dd:d9:dd:c25:c25a:d00a:fde0/1282c19:dd:d9:dd:c25:c25a:d00a:fde0
2262c19:dd:d9:dd:c25:c25a:d00a:fde1/1282c19:dd:d9:dd:c25:c25a:d00a:fde1
2272c19:dd:d9:dd:c25:c25a:d00a:fde2/1282c19:dd:d9:dd:c25:c25a:d00a:fde2
2282c19:dd:d9:dd:c25:c25a:d00a:fde3/1282c19:dd:d9:dd:c25:c25a:d00a:fde3
2292c19:dd:d9:dd:c25:c25a:d00a:fde4/1282c19:dd:d9:dd:c25:c25a:d00a:fde4
2302c19:dd:d9:dd:c25:c25a:d00a:fde5/1282c19:dd:d9:dd:c25:c25a:d00a:fde5
2312c19:dd:d9:dd:c25:c25a:d00a:fde6/1282c19:dd:d9:dd:c25:c25a:d00a:fde6
2322c19:dd:d9:dd:c25:c25a:d00a:fde7/1282c19:dd:d9:dd:c25:c25a:d00a:fde7
2332c19:dd:d9:dd:c25:c25a:d00a:fde8/1282c19:dd:d9:dd:c25:c25a:d00a:fde8
2342c19:dd:d9:dd:c25:c25a:d00a:fde9/1282c19:dd:d9:dd:c25:c25a:d00a:fde9
2352c19:dd:d9:dd:c25:c25a:d00a:fdea/1282c19:dd:d9:dd:c25:c25a:d00a:fdea
2362c19:dd:d9:dd:c25:c25a:d00a:fdeb/1282c19:dd:d9:dd:c25:c25a:d00a:fdeb
2372c19:dd:d9:dd:c25:c25a:d00a:fdec/1282c19:dd:d9:dd:c25:c25a:d00a:fdec
2382c19:dd:d9:dd:c25:c25a:d00a:fded/1282c19:dd:d9:dd:c25:c25a:d00a:fded
2392c19:dd:d9:dd:c25:c25a:d00a:fdee/1282c19:dd:d9:dd:c25:c25a:d00a:fdee
2402c19:dd:d9:dd:c25:c25a:d00a:fdef/1282c19:dd:d9:dd:c25:c25a:d00a:fdef
2412c19:dd:d9:dd:c25:c25a:d00a:fdf0/1282c19:dd:d9:dd:c25:c25a:d00a:fdf0
2422c19:dd:d9:dd:c25:c25a:d00a:fdf1/1282c19:dd:d9:dd:c25:c25a:d00a:fdf1
2432c19:dd:d9:dd:c25:c25a:d00a:fdf2/1282c19:dd:d9:dd:c25:c25a:d00a:fdf2
2442c19:dd:d9:dd:c25:c25a:d00a:fdf3/1282c19:dd:d9:dd:c25:c25a:d00a:fdf3
2452c19:dd:d9:dd:c25:c25a:d00a:fdf4/1282c19:dd:d9:dd:c25:c25a:d00a:fdf4
2462c19:dd:d9:dd:c25:c25a:d00a:fdf5/1282c19:dd:d9:dd:c25:c25a:d00a:fdf5
2472c19:dd:d9:dd:c25:c25a:d00a:fdf6/1282c19:dd:d9:dd:c25:c25a:d00a:fdf6
2482c19:dd:d9:dd:c25:c25a:d00a:fdf7/1282c19:dd:d9:dd:c25:c25a:d00a:fdf7
2492c19:dd:d9:dd:c25:c25a:d00a:fdf8/1282c19:dd:d9:dd:c25:c25a:d00a:fdf8
2502c19:dd:d9:dd:c25:c25a:d00a:fdf9/1282c19:dd:d9:dd:c25:c25a:d00a:fdf9
2512c19:dd:d9:dd:c25:c25a:d00a:fdfa/1282c19:dd:d9:dd:c25:c25a:d00a:fdfa
2522c19:dd:d9:dd:c25:c25a:d00a:fdfb/1282c19:dd:d9:dd:c25:c25a:d00a:fdfb
2532c19:dd:d9:dd:c25:c25a:d00a:fdfc/1282c19:dd:d9:dd:c25:c25a:d00a:fdfc
2542c19:dd:d9:dd:c25:c25a:d00a:fdfd/1282c19:dd:d9:dd:c25:c25a:d00a:fdfd
2552c19:dd:d9:dd:c25:c25a:d00a:fdfe/1282c19:dd:d9:dd:c25:c25a:d00a:fdfe
2562c19:dd:d9:dd:c25:c25a:d00a:fdff/1282c19:dd:d9:dd:c25:c25a:d00a:fdff

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.