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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:c25:c25f:dd4e:dd:dd:af00/120
First address
2c19:dd:c25:c25f:dd4e:dd:dd:af00
Last address
2c19:dd:c25:c25f:dd4e:dd:dd:afff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25f:dd4e:00dd:00dd:af00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
f.a.d.d.0.0.d.d.0.0.e.4.d.d.f.5.2.c.5.2.c.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:c25:c25f:dd4e:dd:dd:af00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:c25:c25f:dd4e:dd:dd:af00/1282c19:dd:c25:c25f:dd4e:dd:dd:af00
22c19:dd:c25:c25f:dd4e:dd:dd:af01/1282c19:dd:c25:c25f:dd4e:dd:dd:af01
32c19:dd:c25:c25f:dd4e:dd:dd:af02/1282c19:dd:c25:c25f:dd4e:dd:dd:af02
42c19:dd:c25:c25f:dd4e:dd:dd:af03/1282c19:dd:c25:c25f:dd4e:dd:dd:af03
52c19:dd:c25:c25f:dd4e:dd:dd:af04/1282c19:dd:c25:c25f:dd4e:dd:dd:af04
62c19:dd:c25:c25f:dd4e:dd:dd:af05/1282c19:dd:c25:c25f:dd4e:dd:dd:af05
72c19:dd:c25:c25f:dd4e:dd:dd:af06/1282c19:dd:c25:c25f:dd4e:dd:dd:af06
82c19:dd:c25:c25f:dd4e:dd:dd:af07/1282c19:dd:c25:c25f:dd4e:dd:dd:af07
92c19:dd:c25:c25f:dd4e:dd:dd:af08/1282c19:dd:c25:c25f:dd4e:dd:dd:af08
102c19:dd:c25:c25f:dd4e:dd:dd:af09/1282c19:dd:c25:c25f:dd4e:dd:dd:af09
112c19:dd:c25:c25f:dd4e:dd:dd:af0a/1282c19:dd:c25:c25f:dd4e:dd:dd:af0a
122c19:dd:c25:c25f:dd4e:dd:dd:af0b/1282c19:dd:c25:c25f:dd4e:dd:dd:af0b
132c19:dd:c25:c25f:dd4e:dd:dd:af0c/1282c19:dd:c25:c25f:dd4e:dd:dd:af0c
142c19:dd:c25:c25f:dd4e:dd:dd:af0d/1282c19:dd:c25:c25f:dd4e:dd:dd:af0d
152c19:dd:c25:c25f:dd4e:dd:dd:af0e/1282c19:dd:c25:c25f:dd4e:dd:dd:af0e
162c19:dd:c25:c25f:dd4e:dd:dd:af0f/1282c19:dd:c25:c25f:dd4e:dd:dd:af0f
172c19:dd:c25:c25f:dd4e:dd:dd:af10/1282c19:dd:c25:c25f:dd4e:dd:dd:af10
182c19:dd:c25:c25f:dd4e:dd:dd:af11/1282c19:dd:c25:c25f:dd4e:dd:dd:af11
192c19:dd:c25:c25f:dd4e:dd:dd:af12/1282c19:dd:c25:c25f:dd4e:dd:dd:af12
202c19:dd:c25:c25f:dd4e:dd:dd:af13/1282c19:dd:c25:c25f:dd4e:dd:dd:af13
212c19:dd:c25:c25f:dd4e:dd:dd:af14/1282c19:dd:c25:c25f:dd4e:dd:dd:af14
222c19:dd:c25:c25f:dd4e:dd:dd:af15/1282c19:dd:c25:c25f:dd4e:dd:dd:af15
232c19:dd:c25:c25f:dd4e:dd:dd:af16/1282c19:dd:c25:c25f:dd4e:dd:dd:af16
242c19:dd:c25:c25f:dd4e:dd:dd:af17/1282c19:dd:c25:c25f:dd4e:dd:dd:af17
252c19:dd:c25:c25f:dd4e:dd:dd:af18/1282c19:dd:c25:c25f:dd4e:dd:dd:af18
262c19:dd:c25:c25f:dd4e:dd:dd:af19/1282c19:dd:c25:c25f:dd4e:dd:dd:af19
272c19:dd:c25:c25f:dd4e:dd:dd:af1a/1282c19:dd:c25:c25f:dd4e:dd:dd:af1a
282c19:dd:c25:c25f:dd4e:dd:dd:af1b/1282c19:dd:c25:c25f:dd4e:dd:dd:af1b
292c19:dd:c25:c25f:dd4e:dd:dd:af1c/1282c19:dd:c25:c25f:dd4e:dd:dd:af1c
302c19:dd:c25:c25f:dd4e:dd:dd:af1d/1282c19:dd:c25:c25f:dd4e:dd:dd:af1d
312c19:dd:c25:c25f:dd4e:dd:dd:af1e/1282c19:dd:c25:c25f:dd4e:dd:dd:af1e
322c19:dd:c25:c25f:dd4e:dd:dd:af1f/1282c19:dd:c25:c25f:dd4e:dd:dd:af1f
332c19:dd:c25:c25f:dd4e:dd:dd:af20/1282c19:dd:c25:c25f:dd4e:dd:dd:af20
342c19:dd:c25:c25f:dd4e:dd:dd:af21/1282c19:dd:c25:c25f:dd4e:dd:dd:af21
352c19:dd:c25:c25f:dd4e:dd:dd:af22/1282c19:dd:c25:c25f:dd4e:dd:dd:af22
362c19:dd:c25:c25f:dd4e:dd:dd:af23/1282c19:dd:c25:c25f:dd4e:dd:dd:af23
372c19:dd:c25:c25f:dd4e:dd:dd:af24/1282c19:dd:c25:c25f:dd4e:dd:dd:af24
382c19:dd:c25:c25f:dd4e:dd:dd:af25/1282c19:dd:c25:c25f:dd4e:dd:dd:af25
392c19:dd:c25:c25f:dd4e:dd:dd:af26/1282c19:dd:c25:c25f:dd4e:dd:dd:af26
402c19:dd:c25:c25f:dd4e:dd:dd:af27/1282c19:dd:c25:c25f:dd4e:dd:dd:af27
412c19:dd:c25:c25f:dd4e:dd:dd:af28/1282c19:dd:c25:c25f:dd4e:dd:dd:af28
422c19:dd:c25:c25f:dd4e:dd:dd:af29/1282c19:dd:c25:c25f:dd4e:dd:dd:af29
432c19:dd:c25:c25f:dd4e:dd:dd:af2a/1282c19:dd:c25:c25f:dd4e:dd:dd:af2a
442c19:dd:c25:c25f:dd4e:dd:dd:af2b/1282c19:dd:c25:c25f:dd4e:dd:dd:af2b
452c19:dd:c25:c25f:dd4e:dd:dd:af2c/1282c19:dd:c25:c25f:dd4e:dd:dd:af2c
462c19:dd:c25:c25f:dd4e:dd:dd:af2d/1282c19:dd:c25:c25f:dd4e:dd:dd:af2d
472c19:dd:c25:c25f:dd4e:dd:dd:af2e/1282c19:dd:c25:c25f:dd4e:dd:dd:af2e
482c19:dd:c25:c25f:dd4e:dd:dd:af2f/1282c19:dd:c25:c25f:dd4e:dd:dd:af2f
492c19:dd:c25:c25f:dd4e:dd:dd:af30/1282c19:dd:c25:c25f:dd4e:dd:dd:af30
502c19:dd:c25:c25f:dd4e:dd:dd:af31/1282c19:dd:c25:c25f:dd4e:dd:dd:af31
512c19:dd:c25:c25f:dd4e:dd:dd:af32/1282c19:dd:c25:c25f:dd4e:dd:dd:af32
522c19:dd:c25:c25f:dd4e:dd:dd:af33/1282c19:dd:c25:c25f:dd4e:dd:dd:af33
532c19:dd:c25:c25f:dd4e:dd:dd:af34/1282c19:dd:c25:c25f:dd4e:dd:dd:af34
542c19:dd:c25:c25f:dd4e:dd:dd:af35/1282c19:dd:c25:c25f:dd4e:dd:dd:af35
552c19:dd:c25:c25f:dd4e:dd:dd:af36/1282c19:dd:c25:c25f:dd4e:dd:dd:af36
562c19:dd:c25:c25f:dd4e:dd:dd:af37/1282c19:dd:c25:c25f:dd4e:dd:dd:af37
572c19:dd:c25:c25f:dd4e:dd:dd:af38/1282c19:dd:c25:c25f:dd4e:dd:dd:af38
582c19:dd:c25:c25f:dd4e:dd:dd:af39/1282c19:dd:c25:c25f:dd4e:dd:dd:af39
592c19:dd:c25:c25f:dd4e:dd:dd:af3a/1282c19:dd:c25:c25f:dd4e:dd:dd:af3a
602c19:dd:c25:c25f:dd4e:dd:dd:af3b/1282c19:dd:c25:c25f:dd4e:dd:dd:af3b
612c19:dd:c25:c25f:dd4e:dd:dd:af3c/1282c19:dd:c25:c25f:dd4e:dd:dd:af3c
622c19:dd:c25:c25f:dd4e:dd:dd:af3d/1282c19:dd:c25:c25f:dd4e:dd:dd:af3d
632c19:dd:c25:c25f:dd4e:dd:dd:af3e/1282c19:dd:c25:c25f:dd4e:dd:dd:af3e
642c19:dd:c25:c25f:dd4e:dd:dd:af3f/1282c19:dd:c25:c25f:dd4e:dd:dd:af3f
652c19:dd:c25:c25f:dd4e:dd:dd:af40/1282c19:dd:c25:c25f:dd4e:dd:dd:af40
662c19:dd:c25:c25f:dd4e:dd:dd:af41/1282c19:dd:c25:c25f:dd4e:dd:dd:af41
672c19:dd:c25:c25f:dd4e:dd:dd:af42/1282c19:dd:c25:c25f:dd4e:dd:dd:af42
682c19:dd:c25:c25f:dd4e:dd:dd:af43/1282c19:dd:c25:c25f:dd4e:dd:dd:af43
692c19:dd:c25:c25f:dd4e:dd:dd:af44/1282c19:dd:c25:c25f:dd4e:dd:dd:af44
702c19:dd:c25:c25f:dd4e:dd:dd:af45/1282c19:dd:c25:c25f:dd4e:dd:dd:af45
712c19:dd:c25:c25f:dd4e:dd:dd:af46/1282c19:dd:c25:c25f:dd4e:dd:dd:af46
722c19:dd:c25:c25f:dd4e:dd:dd:af47/1282c19:dd:c25:c25f:dd4e:dd:dd:af47
732c19:dd:c25:c25f:dd4e:dd:dd:af48/1282c19:dd:c25:c25f:dd4e:dd:dd:af48
742c19:dd:c25:c25f:dd4e:dd:dd:af49/1282c19:dd:c25:c25f:dd4e:dd:dd:af49
752c19:dd:c25:c25f:dd4e:dd:dd:af4a/1282c19:dd:c25:c25f:dd4e:dd:dd:af4a
762c19:dd:c25:c25f:dd4e:dd:dd:af4b/1282c19:dd:c25:c25f:dd4e:dd:dd:af4b
772c19:dd:c25:c25f:dd4e:dd:dd:af4c/1282c19:dd:c25:c25f:dd4e:dd:dd:af4c
782c19:dd:c25:c25f:dd4e:dd:dd:af4d/1282c19:dd:c25:c25f:dd4e:dd:dd:af4d
792c19:dd:c25:c25f:dd4e:dd:dd:af4e/1282c19:dd:c25:c25f:dd4e:dd:dd:af4e
802c19:dd:c25:c25f:dd4e:dd:dd:af4f/1282c19:dd:c25:c25f:dd4e:dd:dd:af4f
812c19:dd:c25:c25f:dd4e:dd:dd:af50/1282c19:dd:c25:c25f:dd4e:dd:dd:af50
822c19:dd:c25:c25f:dd4e:dd:dd:af51/1282c19:dd:c25:c25f:dd4e:dd:dd:af51
832c19:dd:c25:c25f:dd4e:dd:dd:af52/1282c19:dd:c25:c25f:dd4e:dd:dd:af52
842c19:dd:c25:c25f:dd4e:dd:dd:af53/1282c19:dd:c25:c25f:dd4e:dd:dd:af53
852c19:dd:c25:c25f:dd4e:dd:dd:af54/1282c19:dd:c25:c25f:dd4e:dd:dd:af54
862c19:dd:c25:c25f:dd4e:dd:dd:af55/1282c19:dd:c25:c25f:dd4e:dd:dd:af55
872c19:dd:c25:c25f:dd4e:dd:dd:af56/1282c19:dd:c25:c25f:dd4e:dd:dd:af56
882c19:dd:c25:c25f:dd4e:dd:dd:af57/1282c19:dd:c25:c25f:dd4e:dd:dd:af57
892c19:dd:c25:c25f:dd4e:dd:dd:af58/1282c19:dd:c25:c25f:dd4e:dd:dd:af58
902c19:dd:c25:c25f:dd4e:dd:dd:af59/1282c19:dd:c25:c25f:dd4e:dd:dd:af59
912c19:dd:c25:c25f:dd4e:dd:dd:af5a/1282c19:dd:c25:c25f:dd4e:dd:dd:af5a
922c19:dd:c25:c25f:dd4e:dd:dd:af5b/1282c19:dd:c25:c25f:dd4e:dd:dd:af5b
932c19:dd:c25:c25f:dd4e:dd:dd:af5c/1282c19:dd:c25:c25f:dd4e:dd:dd:af5c
942c19:dd:c25:c25f:dd4e:dd:dd:af5d/1282c19:dd:c25:c25f:dd4e:dd:dd:af5d
952c19:dd:c25:c25f:dd4e:dd:dd:af5e/1282c19:dd:c25:c25f:dd4e:dd:dd:af5e
962c19:dd:c25:c25f:dd4e:dd:dd:af5f/1282c19:dd:c25:c25f:dd4e:dd:dd:af5f
972c19:dd:c25:c25f:dd4e:dd:dd:af60/1282c19:dd:c25:c25f:dd4e:dd:dd:af60
982c19:dd:c25:c25f:dd4e:dd:dd:af61/1282c19:dd:c25:c25f:dd4e:dd:dd:af61
992c19:dd:c25:c25f:dd4e:dd:dd:af62/1282c19:dd:c25:c25f:dd4e:dd:dd:af62
1002c19:dd:c25:c25f:dd4e:dd:dd:af63/1282c19:dd:c25:c25f:dd4e:dd:dd:af63
1012c19:dd:c25:c25f:dd4e:dd:dd:af64/1282c19:dd:c25:c25f:dd4e:dd:dd:af64
1022c19:dd:c25:c25f:dd4e:dd:dd:af65/1282c19:dd:c25:c25f:dd4e:dd:dd:af65
1032c19:dd:c25:c25f:dd4e:dd:dd:af66/1282c19:dd:c25:c25f:dd4e:dd:dd:af66
1042c19:dd:c25:c25f:dd4e:dd:dd:af67/1282c19:dd:c25:c25f:dd4e:dd:dd:af67
1052c19:dd:c25:c25f:dd4e:dd:dd:af68/1282c19:dd:c25:c25f:dd4e:dd:dd:af68
1062c19:dd:c25:c25f:dd4e:dd:dd:af69/1282c19:dd:c25:c25f:dd4e:dd:dd:af69
1072c19:dd:c25:c25f:dd4e:dd:dd:af6a/1282c19:dd:c25:c25f:dd4e:dd:dd:af6a
1082c19:dd:c25:c25f:dd4e:dd:dd:af6b/1282c19:dd:c25:c25f:dd4e:dd:dd:af6b
1092c19:dd:c25:c25f:dd4e:dd:dd:af6c/1282c19:dd:c25:c25f:dd4e:dd:dd:af6c
1102c19:dd:c25:c25f:dd4e:dd:dd:af6d/1282c19:dd:c25:c25f:dd4e:dd:dd:af6d
1112c19:dd:c25:c25f:dd4e:dd:dd:af6e/1282c19:dd:c25:c25f:dd4e:dd:dd:af6e
1122c19:dd:c25:c25f:dd4e:dd:dd:af6f/1282c19:dd:c25:c25f:dd4e:dd:dd:af6f
1132c19:dd:c25:c25f:dd4e:dd:dd:af70/1282c19:dd:c25:c25f:dd4e:dd:dd:af70
1142c19:dd:c25:c25f:dd4e:dd:dd:af71/1282c19:dd:c25:c25f:dd4e:dd:dd:af71
1152c19:dd:c25:c25f:dd4e:dd:dd:af72/1282c19:dd:c25:c25f:dd4e:dd:dd:af72
1162c19:dd:c25:c25f:dd4e:dd:dd:af73/1282c19:dd:c25:c25f:dd4e:dd:dd:af73
1172c19:dd:c25:c25f:dd4e:dd:dd:af74/1282c19:dd:c25:c25f:dd4e:dd:dd:af74
1182c19:dd:c25:c25f:dd4e:dd:dd:af75/1282c19:dd:c25:c25f:dd4e:dd:dd:af75
1192c19:dd:c25:c25f:dd4e:dd:dd:af76/1282c19:dd:c25:c25f:dd4e:dd:dd:af76
1202c19:dd:c25:c25f:dd4e:dd:dd:af77/1282c19:dd:c25:c25f:dd4e:dd:dd:af77
1212c19:dd:c25:c25f:dd4e:dd:dd:af78/1282c19:dd:c25:c25f:dd4e:dd:dd:af78
1222c19:dd:c25:c25f:dd4e:dd:dd:af79/1282c19:dd:c25:c25f:dd4e:dd:dd:af79
1232c19:dd:c25:c25f:dd4e:dd:dd:af7a/1282c19:dd:c25:c25f:dd4e:dd:dd:af7a
1242c19:dd:c25:c25f:dd4e:dd:dd:af7b/1282c19:dd:c25:c25f:dd4e:dd:dd:af7b
1252c19:dd:c25:c25f:dd4e:dd:dd:af7c/1282c19:dd:c25:c25f:dd4e:dd:dd:af7c
1262c19:dd:c25:c25f:dd4e:dd:dd:af7d/1282c19:dd:c25:c25f:dd4e:dd:dd:af7d
1272c19:dd:c25:c25f:dd4e:dd:dd:af7e/1282c19:dd:c25:c25f:dd4e:dd:dd:af7e
1282c19:dd:c25:c25f:dd4e:dd:dd:af7f/1282c19:dd:c25:c25f:dd4e:dd:dd:af7f
1292c19:dd:c25:c25f:dd4e:dd:dd:af80/1282c19:dd:c25:c25f:dd4e:dd:dd:af80
1302c19:dd:c25:c25f:dd4e:dd:dd:af81/1282c19:dd:c25:c25f:dd4e:dd:dd:af81
1312c19:dd:c25:c25f:dd4e:dd:dd:af82/1282c19:dd:c25:c25f:dd4e:dd:dd:af82
1322c19:dd:c25:c25f:dd4e:dd:dd:af83/1282c19:dd:c25:c25f:dd4e:dd:dd:af83
1332c19:dd:c25:c25f:dd4e:dd:dd:af84/1282c19:dd:c25:c25f:dd4e:dd:dd:af84
1342c19:dd:c25:c25f:dd4e:dd:dd:af85/1282c19:dd:c25:c25f:dd4e:dd:dd:af85
1352c19:dd:c25:c25f:dd4e:dd:dd:af86/1282c19:dd:c25:c25f:dd4e:dd:dd:af86
1362c19:dd:c25:c25f:dd4e:dd:dd:af87/1282c19:dd:c25:c25f:dd4e:dd:dd:af87
1372c19:dd:c25:c25f:dd4e:dd:dd:af88/1282c19:dd:c25:c25f:dd4e:dd:dd:af88
1382c19:dd:c25:c25f:dd4e:dd:dd:af89/1282c19:dd:c25:c25f:dd4e:dd:dd:af89
1392c19:dd:c25:c25f:dd4e:dd:dd:af8a/1282c19:dd:c25:c25f:dd4e:dd:dd:af8a
1402c19:dd:c25:c25f:dd4e:dd:dd:af8b/1282c19:dd:c25:c25f:dd4e:dd:dd:af8b
1412c19:dd:c25:c25f:dd4e:dd:dd:af8c/1282c19:dd:c25:c25f:dd4e:dd:dd:af8c
1422c19:dd:c25:c25f:dd4e:dd:dd:af8d/1282c19:dd:c25:c25f:dd4e:dd:dd:af8d
1432c19:dd:c25:c25f:dd4e:dd:dd:af8e/1282c19:dd:c25:c25f:dd4e:dd:dd:af8e
1442c19:dd:c25:c25f:dd4e:dd:dd:af8f/1282c19:dd:c25:c25f:dd4e:dd:dd:af8f
1452c19:dd:c25:c25f:dd4e:dd:dd:af90/1282c19:dd:c25:c25f:dd4e:dd:dd:af90
1462c19:dd:c25:c25f:dd4e:dd:dd:af91/1282c19:dd:c25:c25f:dd4e:dd:dd:af91
1472c19:dd:c25:c25f:dd4e:dd:dd:af92/1282c19:dd:c25:c25f:dd4e:dd:dd:af92
1482c19:dd:c25:c25f:dd4e:dd:dd:af93/1282c19:dd:c25:c25f:dd4e:dd:dd:af93
1492c19:dd:c25:c25f:dd4e:dd:dd:af94/1282c19:dd:c25:c25f:dd4e:dd:dd:af94
1502c19:dd:c25:c25f:dd4e:dd:dd:af95/1282c19:dd:c25:c25f:dd4e:dd:dd:af95
1512c19:dd:c25:c25f:dd4e:dd:dd:af96/1282c19:dd:c25:c25f:dd4e:dd:dd:af96
1522c19:dd:c25:c25f:dd4e:dd:dd:af97/1282c19:dd:c25:c25f:dd4e:dd:dd:af97
1532c19:dd:c25:c25f:dd4e:dd:dd:af98/1282c19:dd:c25:c25f:dd4e:dd:dd:af98
1542c19:dd:c25:c25f:dd4e:dd:dd:af99/1282c19:dd:c25:c25f:dd4e:dd:dd:af99
1552c19:dd:c25:c25f:dd4e:dd:dd:af9a/1282c19:dd:c25:c25f:dd4e:dd:dd:af9a
1562c19:dd:c25:c25f:dd4e:dd:dd:af9b/1282c19:dd:c25:c25f:dd4e:dd:dd:af9b
1572c19:dd:c25:c25f:dd4e:dd:dd:af9c/1282c19:dd:c25:c25f:dd4e:dd:dd:af9c
1582c19:dd:c25:c25f:dd4e:dd:dd:af9d/1282c19:dd:c25:c25f:dd4e:dd:dd:af9d
1592c19:dd:c25:c25f:dd4e:dd:dd:af9e/1282c19:dd:c25:c25f:dd4e:dd:dd:af9e
1602c19:dd:c25:c25f:dd4e:dd:dd:af9f/1282c19:dd:c25:c25f:dd4e:dd:dd:af9f
1612c19:dd:c25:c25f:dd4e:dd:dd:afa0/1282c19:dd:c25:c25f:dd4e:dd:dd:afa0
1622c19:dd:c25:c25f:dd4e:dd:dd:afa1/1282c19:dd:c25:c25f:dd4e:dd:dd:afa1
1632c19:dd:c25:c25f:dd4e:dd:dd:afa2/1282c19:dd:c25:c25f:dd4e:dd:dd:afa2
1642c19:dd:c25:c25f:dd4e:dd:dd:afa3/1282c19:dd:c25:c25f:dd4e:dd:dd:afa3
1652c19:dd:c25:c25f:dd4e:dd:dd:afa4/1282c19:dd:c25:c25f:dd4e:dd:dd:afa4
1662c19:dd:c25:c25f:dd4e:dd:dd:afa5/1282c19:dd:c25:c25f:dd4e:dd:dd:afa5
1672c19:dd:c25:c25f:dd4e:dd:dd:afa6/1282c19:dd:c25:c25f:dd4e:dd:dd:afa6
1682c19:dd:c25:c25f:dd4e:dd:dd:afa7/1282c19:dd:c25:c25f:dd4e:dd:dd:afa7
1692c19:dd:c25:c25f:dd4e:dd:dd:afa8/1282c19:dd:c25:c25f:dd4e:dd:dd:afa8
1702c19:dd:c25:c25f:dd4e:dd:dd:afa9/1282c19:dd:c25:c25f:dd4e:dd:dd:afa9
1712c19:dd:c25:c25f:dd4e:dd:dd:afaa/1282c19:dd:c25:c25f:dd4e:dd:dd:afaa
1722c19:dd:c25:c25f:dd4e:dd:dd:afab/1282c19:dd:c25:c25f:dd4e:dd:dd:afab
1732c19:dd:c25:c25f:dd4e:dd:dd:afac/1282c19:dd:c25:c25f:dd4e:dd:dd:afac
1742c19:dd:c25:c25f:dd4e:dd:dd:afad/1282c19:dd:c25:c25f:dd4e:dd:dd:afad
1752c19:dd:c25:c25f:dd4e:dd:dd:afae/1282c19:dd:c25:c25f:dd4e:dd:dd:afae
1762c19:dd:c25:c25f:dd4e:dd:dd:afaf/1282c19:dd:c25:c25f:dd4e:dd:dd:afaf
1772c19:dd:c25:c25f:dd4e:dd:dd:afb0/1282c19:dd:c25:c25f:dd4e:dd:dd:afb0
1782c19:dd:c25:c25f:dd4e:dd:dd:afb1/1282c19:dd:c25:c25f:dd4e:dd:dd:afb1
1792c19:dd:c25:c25f:dd4e:dd:dd:afb2/1282c19:dd:c25:c25f:dd4e:dd:dd:afb2
1802c19:dd:c25:c25f:dd4e:dd:dd:afb3/1282c19:dd:c25:c25f:dd4e:dd:dd:afb3
1812c19:dd:c25:c25f:dd4e:dd:dd:afb4/1282c19:dd:c25:c25f:dd4e:dd:dd:afb4
1822c19:dd:c25:c25f:dd4e:dd:dd:afb5/1282c19:dd:c25:c25f:dd4e:dd:dd:afb5
1832c19:dd:c25:c25f:dd4e:dd:dd:afb6/1282c19:dd:c25:c25f:dd4e:dd:dd:afb6
1842c19:dd:c25:c25f:dd4e:dd:dd:afb7/1282c19:dd:c25:c25f:dd4e:dd:dd:afb7
1852c19:dd:c25:c25f:dd4e:dd:dd:afb8/1282c19:dd:c25:c25f:dd4e:dd:dd:afb8
1862c19:dd:c25:c25f:dd4e:dd:dd:afb9/1282c19:dd:c25:c25f:dd4e:dd:dd:afb9
1872c19:dd:c25:c25f:dd4e:dd:dd:afba/1282c19:dd:c25:c25f:dd4e:dd:dd:afba
1882c19:dd:c25:c25f:dd4e:dd:dd:afbb/1282c19:dd:c25:c25f:dd4e:dd:dd:afbb
1892c19:dd:c25:c25f:dd4e:dd:dd:afbc/1282c19:dd:c25:c25f:dd4e:dd:dd:afbc
1902c19:dd:c25:c25f:dd4e:dd:dd:afbd/1282c19:dd:c25:c25f:dd4e:dd:dd:afbd
1912c19:dd:c25:c25f:dd4e:dd:dd:afbe/1282c19:dd:c25:c25f:dd4e:dd:dd:afbe
1922c19:dd:c25:c25f:dd4e:dd:dd:afbf/1282c19:dd:c25:c25f:dd4e:dd:dd:afbf
1932c19:dd:c25:c25f:dd4e:dd:dd:afc0/1282c19:dd:c25:c25f:dd4e:dd:dd:afc0
1942c19:dd:c25:c25f:dd4e:dd:dd:afc1/1282c19:dd:c25:c25f:dd4e:dd:dd:afc1
1952c19:dd:c25:c25f:dd4e:dd:dd:afc2/1282c19:dd:c25:c25f:dd4e:dd:dd:afc2
1962c19:dd:c25:c25f:dd4e:dd:dd:afc3/1282c19:dd:c25:c25f:dd4e:dd:dd:afc3
1972c19:dd:c25:c25f:dd4e:dd:dd:afc4/1282c19:dd:c25:c25f:dd4e:dd:dd:afc4
1982c19:dd:c25:c25f:dd4e:dd:dd:afc5/1282c19:dd:c25:c25f:dd4e:dd:dd:afc5
1992c19:dd:c25:c25f:dd4e:dd:dd:afc6/1282c19:dd:c25:c25f:dd4e:dd:dd:afc6
2002c19:dd:c25:c25f:dd4e:dd:dd:afc7/1282c19:dd:c25:c25f:dd4e:dd:dd:afc7
2012c19:dd:c25:c25f:dd4e:dd:dd:afc8/1282c19:dd:c25:c25f:dd4e:dd:dd:afc8
2022c19:dd:c25:c25f:dd4e:dd:dd:afc9/1282c19:dd:c25:c25f:dd4e:dd:dd:afc9
2032c19:dd:c25:c25f:dd4e:dd:dd:afca/1282c19:dd:c25:c25f:dd4e:dd:dd:afca
2042c19:dd:c25:c25f:dd4e:dd:dd:afcb/1282c19:dd:c25:c25f:dd4e:dd:dd:afcb
2052c19:dd:c25:c25f:dd4e:dd:dd:afcc/1282c19:dd:c25:c25f:dd4e:dd:dd:afcc
2062c19:dd:c25:c25f:dd4e:dd:dd:afcd/1282c19:dd:c25:c25f:dd4e:dd:dd:afcd
2072c19:dd:c25:c25f:dd4e:dd:dd:afce/1282c19:dd:c25:c25f:dd4e:dd:dd:afce
2082c19:dd:c25:c25f:dd4e:dd:dd:afcf/1282c19:dd:c25:c25f:dd4e:dd:dd:afcf
2092c19:dd:c25:c25f:dd4e:dd:dd:afd0/1282c19:dd:c25:c25f:dd4e:dd:dd:afd0
2102c19:dd:c25:c25f:dd4e:dd:dd:afd1/1282c19:dd:c25:c25f:dd4e:dd:dd:afd1
2112c19:dd:c25:c25f:dd4e:dd:dd:afd2/1282c19:dd:c25:c25f:dd4e:dd:dd:afd2
2122c19:dd:c25:c25f:dd4e:dd:dd:afd3/1282c19:dd:c25:c25f:dd4e:dd:dd:afd3
2132c19:dd:c25:c25f:dd4e:dd:dd:afd4/1282c19:dd:c25:c25f:dd4e:dd:dd:afd4
2142c19:dd:c25:c25f:dd4e:dd:dd:afd5/1282c19:dd:c25:c25f:dd4e:dd:dd:afd5
2152c19:dd:c25:c25f:dd4e:dd:dd:afd6/1282c19:dd:c25:c25f:dd4e:dd:dd:afd6
2162c19:dd:c25:c25f:dd4e:dd:dd:afd7/1282c19:dd:c25:c25f:dd4e:dd:dd:afd7
2172c19:dd:c25:c25f:dd4e:dd:dd:afd8/1282c19:dd:c25:c25f:dd4e:dd:dd:afd8
2182c19:dd:c25:c25f:dd4e:dd:dd:afd9/1282c19:dd:c25:c25f:dd4e:dd:dd:afd9
2192c19:dd:c25:c25f:dd4e:dd:dd:afda/1282c19:dd:c25:c25f:dd4e:dd:dd:afda
2202c19:dd:c25:c25f:dd4e:dd:dd:afdb/1282c19:dd:c25:c25f:dd4e:dd:dd:afdb
2212c19:dd:c25:c25f:dd4e:dd:dd:afdc/1282c19:dd:c25:c25f:dd4e:dd:dd:afdc
2222c19:dd:c25:c25f:dd4e:dd:dd:afdd/1282c19:dd:c25:c25f:dd4e:dd:dd:afdd
2232c19:dd:c25:c25f:dd4e:dd:dd:afde/1282c19:dd:c25:c25f:dd4e:dd:dd:afde
2242c19:dd:c25:c25f:dd4e:dd:dd:afdf/1282c19:dd:c25:c25f:dd4e:dd:dd:afdf
2252c19:dd:c25:c25f:dd4e:dd:dd:afe0/1282c19:dd:c25:c25f:dd4e:dd:dd:afe0
2262c19:dd:c25:c25f:dd4e:dd:dd:afe1/1282c19:dd:c25:c25f:dd4e:dd:dd:afe1
2272c19:dd:c25:c25f:dd4e:dd:dd:afe2/1282c19:dd:c25:c25f:dd4e:dd:dd:afe2
2282c19:dd:c25:c25f:dd4e:dd:dd:afe3/1282c19:dd:c25:c25f:dd4e:dd:dd:afe3
2292c19:dd:c25:c25f:dd4e:dd:dd:afe4/1282c19:dd:c25:c25f:dd4e:dd:dd:afe4
2302c19:dd:c25:c25f:dd4e:dd:dd:afe5/1282c19:dd:c25:c25f:dd4e:dd:dd:afe5
2312c19:dd:c25:c25f:dd4e:dd:dd:afe6/1282c19:dd:c25:c25f:dd4e:dd:dd:afe6
2322c19:dd:c25:c25f:dd4e:dd:dd:afe7/1282c19:dd:c25:c25f:dd4e:dd:dd:afe7
2332c19:dd:c25:c25f:dd4e:dd:dd:afe8/1282c19:dd:c25:c25f:dd4e:dd:dd:afe8
2342c19:dd:c25:c25f:dd4e:dd:dd:afe9/1282c19:dd:c25:c25f:dd4e:dd:dd:afe9
2352c19:dd:c25:c25f:dd4e:dd:dd:afea/1282c19:dd:c25:c25f:dd4e:dd:dd:afea
2362c19:dd:c25:c25f:dd4e:dd:dd:afeb/1282c19:dd:c25:c25f:dd4e:dd:dd:afeb
2372c19:dd:c25:c25f:dd4e:dd:dd:afec/1282c19:dd:c25:c25f:dd4e:dd:dd:afec
2382c19:dd:c25:c25f:dd4e:dd:dd:afed/1282c19:dd:c25:c25f:dd4e:dd:dd:afed
2392c19:dd:c25:c25f:dd4e:dd:dd:afee/1282c19:dd:c25:c25f:dd4e:dd:dd:afee
2402c19:dd:c25:c25f:dd4e:dd:dd:afef/1282c19:dd:c25:c25f:dd4e:dd:dd:afef
2412c19:dd:c25:c25f:dd4e:dd:dd:aff0/1282c19:dd:c25:c25f:dd4e:dd:dd:aff0
2422c19:dd:c25:c25f:dd4e:dd:dd:aff1/1282c19:dd:c25:c25f:dd4e:dd:dd:aff1
2432c19:dd:c25:c25f:dd4e:dd:dd:aff2/1282c19:dd:c25:c25f:dd4e:dd:dd:aff2
2442c19:dd:c25:c25f:dd4e:dd:dd:aff3/1282c19:dd:c25:c25f:dd4e:dd:dd:aff3
2452c19:dd:c25:c25f:dd4e:dd:dd:aff4/1282c19:dd:c25:c25f:dd4e:dd:dd:aff4
2462c19:dd:c25:c25f:dd4e:dd:dd:aff5/1282c19:dd:c25:c25f:dd4e:dd:dd:aff5
2472c19:dd:c25:c25f:dd4e:dd:dd:aff6/1282c19:dd:c25:c25f:dd4e:dd:dd:aff6
2482c19:dd:c25:c25f:dd4e:dd:dd:aff7/1282c19:dd:c25:c25f:dd4e:dd:dd:aff7
2492c19:dd:c25:c25f:dd4e:dd:dd:aff8/1282c19:dd:c25:c25f:dd4e:dd:dd:aff8
2502c19:dd:c25:c25f:dd4e:dd:dd:aff9/1282c19:dd:c25:c25f:dd4e:dd:dd:aff9
2512c19:dd:c25:c25f:dd4e:dd:dd:affa/1282c19:dd:c25:c25f:dd4e:dd:dd:affa
2522c19:dd:c25:c25f:dd4e:dd:dd:affb/1282c19:dd:c25:c25f:dd4e:dd:dd:affb
2532c19:dd:c25:c25f:dd4e:dd:dd:affc/1282c19:dd:c25:c25f:dd4e:dd:dd:affc
2542c19:dd:c25:c25f:dd4e:dd:dd:affd/1282c19:dd:c25:c25f:dd4e:dd:dd:affd
2552c19:dd:c25:c25f:dd4e:dd:dd:affe/1282c19:dd:c25:c25f:dd4e:dd:dd:affe
2562c19:dd:c25:c25f:dd4e:dd:dd:afff/1282c19:dd:c25:c25f:dd4e:dd:dd:afff

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.